Module : Contractual Relation and Contract Management
We shall call the group, which is involved with construction as contractor.
In the civil engineering project, in a narrow sense, ideas of owners is
translated into engineering. Creation by designer/architect and is given real
force by contractor. We have a three party system as This is the simple model for the party involved in the civil engineering
construction. These three bodies are having contradictory objectives, but they
work in non-adversery conditions and should help each other.
In the civil engineering project, major activities are - a. Design b.
Construction
All the activity and process are to help them. Thus, we can broadly say that
design is (shown on the next slide ) c.
d. Thus, the persons involved in
design are involved with the mechanics and properties of materials. We shall
call the group of people involved in designs as designer. A designer may be a
person or a group of persons or a company.
e. Other engineering creation
of designer has to translate into the real facilities. This is process of
construction, which is f. g. Contractual Relations
h. During the life cycle of projects, various
parties come together and work to fulfill objective of the project. We need to
know how these parties are communicating to each other and what ways are they
communicating among themselves. The first point is called delivery methods or
contractual relations and the second issues are termed as type of contracts. The
flow of information between various parties involved takes place in many ways.
i.e . there are different approaches used to organize the project team to manage
the entire design and construction process. Thus we shall discuss various
delivery methods. The relations existing between various parties also vary in
terms of monetary payment and goods as well as service delivery. These points we
shall discuss for type of contracts.
i. The owner needs to know how to communicate with contractor or designer.
Designer or contractor can direct report to him or owner can hire a person or
company which can help him in fixing, communicating designer, contractor. There
are other many possibility such that he can have in-house specialists who can
help him in designing or supervising the work. Similarly, owner can pay the
contractor or designer based on unit work of execution or percentage of the
total cost based on the contractual agreements. In this chapter, we shall
discuss the various arrangements between project team and contractual agreements
existing between them. We shall also discuss the process of awarding contracts,
documents involved.
j. Although the exact nature of arrangement in terms of reporting sub
reporting getting feed-back, payments of execution is unique to the particular
project, these discussions will help us in understanding particular project team
arrangement. Also, we can make our own arrangement depending upon the local
nature of the project.
From the degree of freedom point of view we can classify the project as a.
Public project. b. Private project. Public project:
As we have discussed
earlier, public project consists of primary infrastructure project. Public
projects work on fixed sets of guideline fixed by particular department. For
example in India, Central Public Works Departments (CPWD) works with their own
rules. These are called CPWD manuals. These manuals are well documented and
describe what to do when and how. Deviation from these documents needs special
permission from apex body depending on the nature of change or sometimes there
is almost no scope of change. Similarly each state government maintains its own
contract rules to execute the work. Like Assam public works departments has its
own way of doing the things. Similarly Indian railways execute the works based
on guidelines fixed by the department. Similar situation are existing in other
countries. As for example, US transport department does the work according to
its own document. But, there are many points common between their contractual
arrangement as well as contractual agreements.
Contracts are selected based on
competition bidding. In our country, public project mainly works on minimum cost
bidding system. In recent year, much effort has been paid to improve the low
cost bidding system by introducing technical bidding and price bidding
separately.

Private project: There are more flexibilities in the private project.
Depending on the nature of the project, the owner or project manager can arrange
the project team. Whom to select, how to select and what kind of information
exchange systems will exists between various project team members is dependent
on the owner. Due to these natures, various forms of delivery methods have
developed in practice. Owner select the designer or contractor based on the
quality and reputation of the contractor plus the negotiated money or
competition bidding.
Contractual Relationship or Delivery methods:
We are going to talk about how different member during of project team gets
organized during the life cycle of the project or in the process of design and
construction in particular, or life cycle of project. The different approaches
are called Delivery methods. In general, the relations existing in a particular
form follows specific pattern. But we shall discuss major arrangement followed
in the construction industry. The following delivery methods cover wide arrange
of contractual arrangements
a. Traditional Methods b. Design- construct c. Project management method
a.
Traditional Method: In this method, owner acts as overall coordinator of
the project. He engages a designer or design form to design the facilities and
also prepare complete set of contract documents. With complete set of contract
documents, owner employs contractor either through negotiation or competitive
bid. The contractor hired is totally responsible for the delivery of the
project. The designer may employ other designer to do the specific work. Such as
many designer takes help of other team to do the electrical,. mechanical design
in the building project and prepare the structural design in- house.
The main designer works as a coordinator of the design-process. Similarly, the
contractor may subcontract out some job to subcontractor. These subcontractors
will be directly reporting to the main contractor. There is no formal agreement
between contractor and designer. Owner himself oversees the quality control.
Sometimes designer may get involved in overseeing construction work depending
upon the owner need.
Thus we can see, for large project, owner needs to maintain an engineering
department to hire designer and contractor and oversees the work.
There are
many variations of these arrangements. Owner may have their own design group and
hires only designer for specific jobs or owner can subcontract the jobs himself
and oversees the project, such as award the contract of piling for one company
and superstructure to other company. A typical government organization in India
such as Central Public Works Department (CPWD), irrigation department works with
this pattern. IIT construction work is generally carried out by this method. A
typical relation is shown in the figure , on the next slide.
The ways fees are paid to contractor or designer depend up the type of contract.
We shall discuss this point later on. It may be unit price, percent of cost or
lump-sum etc. depending on the nature and agreement in the project. We shall now
discuss the advantages and disadvantages of this contractual agreement.
Advantage:
a. As the owner receives complete set of drawing and specification of the
work, he gets the fixed price of the project. He can award the contract in any
type of contract; he will have good idea of the cost of project.
b. This
system is followed in public sector project. Owner, designer, contractor works
in the fixed frame work. They might be working many projects. Generally welldocumentations are available for different process. CPWD maintains well
documented procedure.
c. Competitive biding is easy to implement as complete
set of contract document is available before construction starts.
d. Owner need not to worry about day to day activity of the project. He gets
involved only at the specific points.
Disadvantage:
a. Contractors and subcontractors have no input in the
design. Material or methods specified may not be available or contractors have
knowledge of efficient methods and materials.
b. It is difficult to have
overlap between design and construction phase. So fast tract construction may
not be possible.
c. Sometimes there may exist different interpretations
of contract document by owner and contractor.
d. The change in the
methods or material of construction may give rise to conflict. Unforeseen
changes are difficult to implement.

Design-Construct
In this method of delivery, design and construction is carried out by the
same company. The company may be a single unit or joint venture of two companies
or more than two companies. A single company can take a job for design and
construction, but the company sub-contract or contract the construction, but
engaged himself in the management of construction. There are different
variations available for this mode of delivery. But common point is that the
same company takes the job from conceptual design phase to construction and
implementation. The variations of this mode are turn-key project.
Design-manage
This method of delivery has been practiced in the specialized job in
industrial sector. Petrochemical industry, manufacturing plants, nuclear plants,
offshore oil drilling platform. In IIT Guwahati , air-conditioning was done by
“Blue Star” as design-construct methods. This method has also been used in
building project recently. A typical relation is shown in figure.
4. Owner is not aware of the construction and design. This lack of knowledge
may be handicapped during maintenance phase.
5. In the traditional form,
owner monitors the quality of conformance with the design document. But in
design-construct method of delivery, there is no standard for the owner to check
and monitor.
6. This arrangement doesn't guaranteed the best possible price.
Project Management Method
There are many variations of this mode of delivery. Some of these variations
are program management; construction management, professional construction
management. In this method of delivery, owner hires a construction management
firm at start of the project and involves them in the project from conceptual
design through implementation [start up]. The degree of involvement of the
construction management firm depends upon the expertise and requirement of the
owner. Owner may involve the management firm to select designer, coordinate the
work between designer and contractor, monitor the constructions. A typical
arrangement is shown in the figure, on the next slide.
Advantages : 1. It establishes the good communication between design and
construction together with the owner awareness and monitering.
2.
Cooperation between different team members increases the value engineering.
3. Designer and contractor can agree on the same coordinated schedules.
4.
Many a time, owner is directly involved with subcontractor, thus, getting
benefit of competition in terms of price.
5. Unforseen changes are easy
to implement.
Disadvantages :
1. Irresponsiveness of any team member can spoil the
coordination.
2. Requires owner knowledge about project management.
3. Risks involved during the execution of project is high.
Types of Contract
Contract is an agreement between two or than two parties
in which one is agreed to provide goods and services to other for which he will
get the return in the some form. The contract is legal document and binding on
both the parties. The form in which return for providing goods and services is
delivered, is called type of contracts. There are different types of contracts
which can be employed in any of the delivery methods. Owner can pay the money to
the contractor, in lump-sum, based on measured work with unit price, based on
percentage plus quantity involved. In the following, we shall briefly discuss
the different type of contract.
a. Lump-sum contract: This is a single fixed price contract. In this
contract, contractor agrees to perform specified job for fixed sum. The owner
provides the contractor exact specification of the work. In this contract both
the parties try to fix the conditions of the work as precisely as possible.
Following are the advantages of the fixed price contract.
a. Owner is
aware of the cost of the project before the project construction starts.
b. It avoids a lot of details and accounting by both owner and contractor.
c. Contractor gets free hand to execute the work.
d. If this contract is
used with design-construct method of delivery, contractor gets opportunity to
use value engineering.

Disadvantage:
a. It is very difficult to accommodate any charge in design and
specification.
b. This contract is as good as the accuracy of the contract document. If
errors exist in the contract document, the contract need to be renegotiated and
hence more risk is involved from the owner ride.
c. In the case of unforeseen hazard during the construction, contractor may
be put in adverse situation.
This type of construct is suited for small job, precisely specified job, low
risk with construction job. This is generally suited for the job where it is
easy to make the measurement. Lump-sum contract should be avoided for
underground work.
Lump-sum contract with design construct method of delivery is often called
turn key contract. Payment by the owner can be carried out in lump-sum contract
as total amount at time or percentage of total cost after finishing certain
amount of work. For example suppose a water tank was awarded as lump-sum
contract. It can be said that 15% of amount will be paid after construction of
foundation 50 % of total amount will be paid after construction of staging and
80% of the total amount will be after the construction of the tank. Rest will be
paid only when the tank becomes operational. Lump-sum contract in often used in
sub-contracting for labour contract. In our country many laborers for
excavation, plastering work with this method.
b. Unit price contract:
In this type of contract, the price is paid per unit
of the work carried out. There are different variations of this type of
contract. Some of them are mentioned below.
Bill of quantities contract: In this type of contract owner provide the
drawing, quantities of work to be done and specification. The contractor bid
based on the unit cost of the items of construction. The contractor overhead,
profit and other expenses can be included in the unit cost of the item of work.
Sometimes contractor quotes the unit price of the work and lump-sum amount
separately as profit overhead. The estimated quantities of the work to be done
called Bill of the quantities is fixed. Minor variation in the quantities is
admissible in this type of contract. The drawing of the work is not suppose to
change. Although change and deviations from original drawing could be accepted
during construction but even then unit price does not change.
This type of construction is usually followed in government sector for large
infrastructure construction. This type of contract provides owner a competitive
bid. Disadvantage of the methods are:
a. Owner needs to measure the quantity of work done in the field, hence
requires owner presence at the site.
b. Final price of the construction is not known precisely until last price
of work is completed. If there is significant difference between the estimated
quantities and the reality of the situation, owner is put in adverse situation.
Mistaken quantities is called unbalanced bid . Significant unbalanced bid now
considered as unethical.
Schedule of rate contract: Many a time, the quantity of work to be executed is
not known before. Contract is signed based on the unit cost of the item of work.
Generally more items are inserted in the contract than to be executed because it
becomes sometimes difficult to exactly specify all the items. There is no
guarantee that all the items mentioned will be used in the construction. This
type of contract are widely used in underground work, flood control and road
constructions. Advantages and disadvantages of this type of contract in the same
as the bill qualities contract. There are other variations of schedule of rate
contract where unit price plus profit is charged as the cost which we shall
discuss next.
c. Cost plus contract: In this contract, the payment is made based on the
work carried out plus the fee which includes overhead, profit etc. Sometimes a
cap is put on the type of contract by provided maximum and minimum cost limit
such as guaranteed maximum cost contract. If project cost exceed this limit,
contractor is responsible for that.
Sometimes incentive clause is also
included if the contractor bring the project before certain specified limit.
The advantage of this type of contract is that considerable overlap is provide

between design and construction. Hence the project can be executed in the fasttract basis. This contract is suitable for the work where it is difficult to
define the task to be done before the awarding the contract.
Stages of awarding contract
The stage of awarding construction contract is dependent of the methods of
delivery of the project. In the tradition way of delivery, contract documents
are prepared after the completion of design. Generally designer helps the owner
to prepare estimate of the project. If owner maintains an engineering
department, an estimate is prepared by the engineering department. Specification
of the items used for construction is very important from point of view of
quality of design and quality of construction. Specification is generally
prepared by the designers. During the design, designer may take owner advice in
preparing specification of the items. The drawing and specification prepared by
designer form the basis for the awarding contract.
A tender notice is advertised in the news paper depending upon the type of work.
It may be in nation newspaper or local news paper. In a large project, tenders
are invited from person/company from any country called the global tendering . A
typical tender notice is given in the table. Sometime this process is carried
out in two stages. In the first stage the aim is to select the contractor who
has good experience of executing the similar kind of job and have required
technical competence. The process is called “pre qualification”. The contract
documents are sold to these pre qualified contractors. Many a time designer
himself identifying the competent contractor based on his experience.
The contract document is bought by the contract or by paying some fees.
Contractor prepares their offer and submit to the owner. The offer by contractor
to the owner is called Tender and process is called submitting tender. Sometime
owner ask to submit the tender in two separate documents. The first offer
provides the specification of the item to be used. This is called “technical bid
”. And price offer is given separate which is “price-bid”.
After getting the tender, owner studies the tender documents, does comparatives
studies and awards the contract to the lowest quoted contractor or who has given
better technical deal. Sometimes contractor quotes the specifications which are
higher or lower than the owner specifications. To get competitive bid, owner may
provide this specification to other contractor and ask them to go for price bid.
There is scope of using value engineering in this process also.
Thus the complete process of awarding contract can be summarized as follows.
1. Preparation of contract document. 2. Advertising the tender, tender notice.
3. Submitting Tender by contractor. 4. Study of the tender by owner
5.
Clarification regarding conditions or specifications
6. Preparing comparative
list
7. Awarding contact
Contract documents
Documents related to awarding contract are called contract documents, generally
it contains following
i. drawing ii. specification of items
iii. general conditions of contract
iv. general explanation
A tender is the offer by the contractor to the owner to construct and the
execute the work according to the drawing, specification (provided by owner or
changed by contractor) and general condition of controls.
Finally all the parties involved in the project (owner and contract) sign the
legal agreement with respect to well defined intentions. If bidding is carried
out with internationally, contract document consists of general conditions of
site, its location local laws regarding labor etc., general condition for
execution of the work etc. Missing
iv. general explanation
A tender is the offer by the contractor to the owner to construct and the
execute the work according to the drawing, specification (provided by owner or
changed by contractor) and general condition of controls.
Finally all the parties involved in the project (owner and contract) sign the
legal agreement with respect to well defined intentions. If bidding is carried
out with internationally, contract document consists of general conditions of
site, its location local laws regarding labor etc., general condition for

execution of the work etc.
Disputes And Arbitration
During the performance of the contract, disputes may arise between the
employer, engineer and contractor for various reasons of default in performance,
progress payment, rates, time, etc. Negotiated amicable settlement is the
endurable, quick solution, which requires mutual trust, cooperation, give and
take policy, flexibility instead of rigidity of one's view, and vision for
future relations. Unresolved disputes can conveniently be resolved through
arbitration, which bears the stamps of law of natural justice, than resolution
in court. Again, arbitration cannot succeed unless there is cooperation between
contractor, client and arbitrator(s). Many times, when the award received is not
palatable to either of the contesting parties, the unhappy party tries to drag
on further in court to set aside the award. This defeats the very purpose of the
arbitration process. The court does not set aside the award on flimsy ground or
sits again for the judgment but on specific grounds. The court may even ask the
arbitrator to review his award if any item is omitted. The responsibility
imposed on the arbitrator is conduct the proceedings with prudence and diligence
and not arbitrarily or whimsically and discharge his responsibilities in a
cordial manner. The reasons for setting aside the award has been set out in
Arbitration Act, 1940, which has since been modified in Arbitration &
Conciliation Act 1996. As per the new Act, the award itself is considered as a
decree and it need not be filed in the court. It is final and binding on both
parties unless disputed by either party. The tendency to challenge the award
should vanish, instead the aim should be to reach a negotiated, agreed, amicable
and early settlement. It is hoped that better awareness and acceptance of this
method fructifies in future.
Why does disputes arise?
1. There are errors, ambiguities and omissions in the drawing and specification.
Also, there is lack of proper coordination during construction.
2. Not
complying with the intent of the contract or not adhering to the standards in
the performance of work(Quality of conformance problem).
3. Incomplete,
delayed, inaccurate response to the question by any of the party in the
contract.
4. Unforeseen changes in sub surface conditions.
5. If site condition differs from those described in contract documents.
6. Extra work or changed work order
7. Not meeting schedule by the
contractor.
8. Inadequate financial strength on the part of the owner,
contractor or subcontractor.
Origin of Arbitration
Resolution of disputes through arbitration is an accepted method from time
immemorial. China, India and Italy are the first few countries that used this
method. British India, from the 18 th century, had regulations on arbitration in
Bengal, Bombay, Madras, etc. The first Indian Act of Arbitration was enacted in
1899; The next was the Arbitration Act 1940; The recent one is Arbitration and
Conciliation Act of 1996.
Arbitration Acts
The arbitration Act, 1940 has been repealed under Section 85 of Arbitration
and Conciliation Act 1996. Not withstanding such repeal, the provisions of the
Arbitration Act 1940 still apply to arbitral proceedings which commenced before
this Act came into force unless otherwise agreed by the parties, but the
Arbitration Act 1996 applies to arbitral proceedings which commenced on or after
the Act came into force.
Principal Differences In Implementation Of Award
The principal differences
between the Indian Arbitration Act 1940 on the one hand and the 1996 Act on the
other regarding the courts powers regarding an award are as shown in Table-1.
Table 1: Principal Differences In Indian Arbitration Act 1940 and Arbitration
Act and Conciliation Act 1996
Indian Arbitration Act 1940
Arbitration
Act and Conciliation Act 1996
Power to modify an award if it is on matter not referred to arbitration [S.15
(a)].
Power to modify and award if it contains an obvious error, which can be amended
without affecting such decisions [S.15 (c)].
Power to remit the award when the award has left undermined any of the matter

referred to Arbitration [S.16 (a)].
Power to remit an award where it discloses error of law apparent upon its face
[S.16 (c)].
Power to set aside the award for misconduct, both legal and personal [S.30].
Power to decide the existence and the validity of arbitration agreement [S.33].
Under S.32 (2)(a)(iv), the court has the power to set aside an award which deals
with a dispute not falling within the terms of the submission to arbitration;
Power to arbitrator for correction of computation, clerical or typographical
errors only.
No power to remit the award the act provides no remedy in case of an
arbitrator not deciding a dispute referred to him;
No power to remit the award. No power to set aside.
No power to set aside the award on the ground of misconduct.
Power to decide the existence limited to the question whether the award decides
a dispute not contemplated by the parties.
No power to decide if the omission by the arbitrator to decide a dispute which
fell within his jurisdiction is valid or not.
Power to decide the validity of the arbitration agreement.
Dr. A.S. Anand, the Hon'ble Chief Justice of India, while addressing a
conference on the dispute resolution for Alternative dispute resolution
organized by the International Centre for Alternative Dispute Resolution, on
12.12.98, stressed the need to give the Panchayats more powers to set up family
courts and conciliation centers in all the districts which will be able to
dispense justice quickly and at less expenses to litigants. He maintained that
the administrative institutions had failed to monitor the status, substance and
pace of litigation in courts. “We have not so far succeeded in developing any
effective mechanism for the pretrial settlement of legal dispute with the result
that there is a heavy inflow of all sorts of civil, commercial and criminal
matters into courts”, the Chief Justice said. Sharing the same concern, it is
considered that and award made under the Arbitration Act 1940 should also be
given the same treatment for enforcement as under the Arbitration and
Conciliation Act 1996.
Module : Estimation and Rate
Analysis(Estimation)
Estimation
General
During construction project planning and implementation, we need to know the
quantities and costs of various items required to meet the objective of the
project. That is, construction project manager has to anticipate the cost of
project. The process of calculation of quantities and costs of various items in
connection with the construction project is called an “estimate”.
An estimate is prepared by first obtaining the quantity of the items required to
complete the project and multiplied by unit cost of the items. Details of the
estimate depend upon the purpose of carrying out estimate.
The preliminary estimate should be accurate enough to produce the cost of the
project within 10% to 15% variations.
During the life cycle of a project, different parties for various reasons
require an estimate. The details and method of estimations depend upon the needs
and level of management decisions.
Suppose a philanthropic organization wants to start an academic institute. The
organization is interested in knowing how much money is required to be spent. It
can be just calculated from the experience with previous project of similar
kind. Such as, 20 thousand money per student has to be invested. If academic
institute is to be planned for one thousand students, 20 x 1000 thousand is
required. Next level of details may be required is how much money is to be
invested on different subheads, equipment, laboratories, hostels etc.
Suppose a philanthropic organization wants to start an academic institute. The
organization is interested in knowing how much money is required to be spent. It
can be just calculated from the experience with previous project of similar
kind. Such as, 20 thousand money per student has to be invested. If academic
institute is to be planned for one thousand students, 20 x 1000 thousand is
required. Next level of details may be required is how much money is to be
invested on different subheads, equipment, laboratories, hostels etc. These can

be calculated based on knowing the area of construction and cost of construction
per unit area. But suppose hostel has to be built based on specific drawing and
specification. Now an estimate will be prepared from the drawing and
specification using specified rules. This estimates form the basis for contract
evaluation by the client.
Similarly when contractor is bidding for the hostel, he will prepare his own
estimate such that he can buy the contract, also gets profit from the execution
of the project. But during construction period the construction, company has to
prepare an estimate for order and supply of the material, also for resource
planning.
Thus we have seen from the above example that the estimate of same item of works
differs in details based as need of the project implementation. Also the level
of accuracy needed for the estimate is dependent on the purpose of estimate.
Like estimate for material supply has to be very accurate because storage of
material will be the burden for the project. But the accuracy of the estimate to
know the total cost to study the feasibility of the project will not be very
high.
Different body involved in preparation of estimate can be grouped into following
three classes.
1. The owner or owner's staff such as project manager.
2. Contractor's
personnel such as senior manager, planner, site management staffs etc.
3. Materials suppliers and contractors
The owner generally employs a project manager/engineer, who helps him in
preparation of contract documents. The contract documents require the bill of
quantities. Also, owner should be aware of the cost to sell the contract. Thus
an estimate is required of various quantities. The owner's project manager
prepares these estimates. Tender for the contract in a construction company is
prepared by higher management. These management are helped by estimators, site
engineers and material supplier to prepare the estimate of the job.
Challenges in Estimating :The job of an estimator is not only to calculate the
quantity and cost of the material, but to co-ordinate different parties involved
in the project or construction in particular. An estimator of the construction
company has to get involved with the site engineer, material supplier,
instrument (plant) manager and senior management staff to obtain the various
details of the cost and explaining the calculation to higher management. An
estimator has to understand the project details, study drawing and
specification, obtain working conditions, labour and equipment productivity and
collecting other data from the site. An estimate also assesses the temporary
work at the site such as formwork for concreting, temporary plant for the
storage of materials. Virtually, an estimator has to build the project on paper
to obtain the right guess.
In the organization, background work for estimation is carried out by higher
management and organizations keeps the details regarding unit cost of the items
called schedule of rate, productivity, and guideline for basic calculation. The
basic calculation is carried out by junior level engineers or assistants.
In preparing detailed estimate, we need to know the following two things
1. Quantities of the items involved.
2. Obtaining cost of the items
involved.
Methods of obtaining quantities of the items involved is called quantity
estimate and method obtaining unit cost of the items involved is called rate
analysis.
Types of Estimate:
Based on the rigor with which an estimate is prepared, the estimate can be
classified as
1. Preliminary estimate.
2. Detailed estimate.
Requirements of preliminary and detailed estimate:
To prepare a preliminary estimate, quantity of work to be planned is measured in
terms of unit of person, built up area, extent of work in kilometer such as a
preliminary estimate of housing can be calculated based on type of house and
number of house to be built. Similar preliminary estimate of highway can be
calculated by knowing the type of road in terms of lane or pavement and length

of the load.
Preliminary Estimate
Different methods of preliminary estimate can be grouped into the following
categories – Time referenced cost estimate
Cost capacity factor
Component
ration/installation cost ratio
Parameter cost
The preliminary estimate is obtained during early phases of project. As the
project progresses, an estimate keeps on getting refined and lastly we get
definitive estimate.
i. Time referenced cost estimate – If the cost of construction of facilities is
known at a certain time, the present cost can be estimated by multiplying it
with the cost index, with reference to that time. Generally government finance
department publishes cost index based on depreciation, etc. But this cost index
is very crude. Construction department keeps the cost index based on the items
and method of construction used. There are some limitations of such method.
During the time, technology changes; productivity of various equipment may
change; degree of competition may be different. One should be aware of all these
factors while using the cost index to estimate the constructed facilities.
ii. Cost capacity factor – This factor refers to the change in cost of built-up
facilities with the change in size of the project of similar type. If C1 and C2
be the cost of facilities to be built and old facilities. Let their size be Q1
and Q2 . We can calculate the cost of the new facility as
Where x is called the capacity factor. Many organizations publish the value of
capacity factor. It is reasonable to consider cost capacity factor between 0.6
to 0.8.
The capacity factor method and time reference method can be combined.
iii. Installation cost ratio – In the industrial project, the equipment to be
installed is known quite earlier to the details for their installation. In such
situations, an estimate is prepared based on the ratio or percentage of the cost
incurred as the installation cost. The organization generally maintains this
type of data. Example- The cost of an equipment is Rs10,00,000, and its
installation cost , including accessories is 50%. Thus the estimated cost is
10,00,000 + ( 0.5 x 10,00,000) = 15,00,000
We can consider the equipment in component wise and calculate the installation
cost individually. This approach will require detailed information, but will be
more accurate.
iv. Unit Parameter cost – In many of the projects, it is possible to obtain the
cost of unit parameter of construction. These parameters may be unit area, unit
volume, etc. This type or procedures are used in building construction.
Residential apartment in our country are generally estimated using this method.
There are different variations of the method. Some of them widely used are as
follows - Residential buildings are generally estimated using this method.
Requirement for detailed estimate:
To calculate the detailed estimate,
complete structural drawing of the facilities to be built up and specification
of the items are necessary. We also need to know the rate of each of the items,
which includes profit of the contractor.
Revised Estimate:
Due to change in the rate of material or change in specification of materials,
an estimate is often required to be modified. Thus, we prepare revised estimate
against the original estimate. In the preparation of revised estimate, original
estimate is also provided such that comparison can be made. There is no change
in structural drawing and additional items are not added in the revised
estimate.
Revised estimate is a detailed estimate. It is also accompanied by the original
estimate for comparative purpose. While submitting the revised estimate, the
reason for revision should also be stated.
Supplementary estimate:
During the execution of project, structural
modification are required or addition work is added for construction. The
estimate for additional work is called supplementary estimate. Supplementary
estimate is also required to be prepared when some of the items are overlooked.

In preparing the supplementary estimate reason for preparing the estimate would
be clearly stated.
Example: Additional partition can be planned in the building. The estimate is
prepared for partitioning as supplementary estimate. Structural / architectural
changes are prerequisite for supplementary estimate.
Rate Analysis
At various stages in the project management, we need to know
how much is cost of executing unit amount of the work
how many equipment or
labour are required to execute unit amount of an item of work.
These things are required for the purpose of eliminating cost of construction,
material planning, labour and equipment allocation in the scheduling etc.
Obtaining the cost of unit amount of an item is called rate analysis. To obtain
the rate of an item, generally following cost are considered.
cost of material
cost of labour cost of equipments, plant tools etc.
overhead cost
profit
The costs of these components are determined from the area survey, schedule of
rates published by central and state government; transportation charges based on
the location of the area. Also we need to know how much is required for
execution of the work. Similarly number of labour and equipment. These things
are bared on both the heuristics and engineering design. Not only specification
is important for obtaining the cost of the work, but one has also to include
quality mentioned during construction we shall discuss this pointing detail
through case study.
a. Cost of material – To obtain the cost of material in the unit amount of an
item, first specification is studied carefully. Quantity of material required is
calculated and multiplied by the cost to obtain the unit cost. Cost includes
freight, transportation, sales tax, insurance, as well as profit. An estimator
has to do his market survey and the area survey before calculating the unit cost
of the material.
b. Cost of labour – Productivity of the labour is very important aspect in
calculation of labour cost. Productivity of the labour depends upon the type of
work, training imparted to the labourer, nature of work, time schedule of the
work, etc. For example, a mason can do more plastering standing on the floor
than working at a height on the scaffolding. Initially, it takes time to learn
the work and gradually productivity increases, which is shown by the learning
curve as follows –
For specific works, different types of labourers, such as skilled and unskilled
labour, mason, carpenter, mazdoor, etc are required to execute the work. Unit
amount of work is obtained based on experience; and their cost is obtained from
the local survey or government wage rules.
c. Cost of equipment - Calculation of work-hour used for equipment is dependent
upon the type of equipment utility. Some equipments are used for specific
purpose where as some of it are used for different work simultaneously.
Generally equipment used individually is calculated for each item of work. For
these equipments, it is not possible to calculate the cost; the equipment charge
can be added as overhead. For example, installation of a batching plant requires
special effort and it is not easy to distribute its initial cost on the
concreting. We can incorporate such kind of work as establishment charges or
overhead.
d. Overhead cost – During the period of construction, a company has to maintain
an office or depreciation of its equipments may take place. This is usually
taken as 2-5% of unit rate.
Part of the overhead is directly related to the construction of an item of work.
Such expenses include –
i. Repair and depreciation of tool and plants
ii. Salaries of supervisors,
etc; who are indirectly involved in the work
iii. Temporary godown and sheds
to store the material at the site
iv. Lighting arrangements
v. Labour
welfare
vi. Safety scheme
vii. Small tools used for work

Such expenses are incurred only when work is under execution. If there is no
work, no expense is required.
Other parts of overhead are permanent in nature. These expenses are throughout
the year. These expenses include –
i. Salaries of office staff,
ii.
Printing and stationary charges,
iii. Electricity and rental charges,
iv. Communication expenses such as telephone, e-mail, etc,
v.
Traveling, etc.
In bigger companies, these expenses are higher compared to smaller contractors.
Measurement In Civil Engineering
Measurement of civil Engineering work executed in the field is carried out based
on thumb rule. Indian standards provide the approximate rules to measure the
quality in the field. They are comprehensive and follows almost all areas.
Following are the list of Indian Standards Indian standards Standard Description
IS 1200 : Part 1 : 1992 Methods of measurement of building and civil engineering
works: Part 1 Earthwork
Measurement Book
Measurement is entered in the table. Every department maintains its measurement
book. A typical page of measurement book is shown on the next slide Project Planning
In the process of planning , alternatives are examined and the best alternative
is chosen. The goal of planning is to minimize resource use (cost) while
satisfactorily completing the task . Efficient use of equipments , material ,
labor and ensuring coordinated effort are the basic aim . The outcome of
planning is predetermined course of action.Thus, the planning creates an orderly
sequence of events, defines strategies to be followed in carrying forth the plan
and describes ultimate disposition of the result. Putting the various activity
of the project in the sequence on the time frame is the process of scheduling .
Scheduling is required for continuous checking of the project (control), for
resource mobilization , to minimize the cost and use of resources optimally.
Various scheduling techniques have been employed to plan the activity in
sequence in project management . In construction project , bar chart and
critical path method (CPM) have been widely used . During the planning process ,
a manager builds the facilities on paper , thus identities each of the various
tasks and time .During construction , these predetermined course of action form
the basis for monitoring and the checking the progress of the work . Following
steps are followed during planning , scheduling and control .
a. Identifying and defining activity,
b. Defining activity interdependence ,
c. Estimate time and resources for each activity ,
d. Constructing the
network,
e. Calculations on network for project time , earliest start and finish of
activity, resource requirement, etc,
f. Project control and project review .
a. Identifying the activity : Activity is well defined task which consumes
time and resources . The identification of activity depends upon the level of
details and the requirement of management .Different levels of leaders requires
different detail in the project planning . For example , the cost of beam can be
an activity in building construction or it can be further split into different
activities such as bar scheduling , making form work , concrete mixing and
casting , curing the beam etc . Generally tasks to be performed in break down
using �Top-Bottom Design� . The work break down structure (WBS) forms the useful
tool to identify the activity . The outcome of this phase is the complete list
of activity to perform the project .
b. Defining activity interdependence : In this step , each of the activity is
considered . It is argued which activity will succeed the activity under
consideration. Thus, we obtain the immediate succeeding activity or immediate
successor . This way of thinking is called forward planning. We can also think
which activity will precede the activity under consideration and similar manner
we can prepare immediate precedence list. This way of thinking is called
Backward Planning Outcome of this step is list of activity together with
immediate preceding or succeeding activity.
This step is carried out by most knowledgeable persons of the team . Generally

these steps are carried at the senior/experience persons in the department or
contractor�s company .
In this condition, cost of the activity generally goes up. The relation between
cost and the duration is given as follows Many a time the base curve approximate as linear as shown below These time-estimates are used in the time-cost optimization , in the critical
path method . We have specified the relations between resource as cost which can
be worked out separately .
i. PERT time estimate : In this technique , it is assumed that the activity
durations follow a stochastic duration . Generally , - distribution is assumed
in the model . To specify the procedure , following three activity durations are
chosen a. Most likely time,
b. Most optimistic time, c. Most pessimistic time.
d. Most likely time : This time is the time when activity has more probability
to occur than any other activity . This is the tallest pick in the probability
distribution, i.e. mode .
e. Most optimistic time : This time has 95% fastest occurrence than the
occurrence of any other activity. This is the shortest duration assumed .We mean
here is that optimistic time has 19 times fastest in every 20-occurrence time.
f. Most pessimistic time :This time has 95% slowest occurrence than the
occurrence of any other activity . This is the longest duration assumed .We mean
here is that pessimistic time has 19 times slowest in every 20-occurrence time.
Based on the above time estimate, the average time taken for the completion of
the activity or job is called expected time. Taking weighted average, we can
obtain the expected time as This result has been derived considering - distribution and weighted average as
one .
The expected time of an activity in series can be summed to calculate the total
time as Frequency distribution of activities Estimation of resources : In order to estimate the resources , the project
manager must consider the efficiency of the machine , productivity of labour ,
learning process , site conditions , impact of weather . For example , person at
floor level can do more plastering than standing on the scaffolding . Similarly
a person's efficiency is less at the start of the work and increases slowly and
reaches the saturation level following the learning curve as shown The above curve is called the learning curve . All these points should be taken
into account while planning resources .
d. Construction the network : In the critical path method , network is a
directed graph . A directed graph is a structure formulated by nodes , which are
tied by directed arrow .
Let be the set of nodes , and be the directed arrow
The graph of the activity network is represented mathematically by the symbol
[N,P] .
There are two logic diagramming formats used in CPM i. Activity on the arrow
.(AOA)
ii. Activity on the node . (AON)
iii. Activity on the arrow (AOA) : In this format , activity is denoted by the
arrow and nodes merely serve as connecting points for the activity . We often
require to use activity with zero time called dummy activity to retain the logic
and grammatical rules of the network . The network is constructed on the logic
that an activity leaving a node cannot begin until all the activity heading into
that node have been completed . This diagramming format has widely been used .
ii. Activity on the node (AON) : Now-a-days , CPM users employ activity on node
format and many of the softwares also use this diagramming format . This format
is also referred to as “Precedence Diagramming” . In this format , logic in the
network is represented by node and precedence arrow . The precedence arrows show

the order sequence and relationship between activities . The logic behind the
network diagram is that an activity cannot start until all preceding activities
are complete .
The logic network simply represents the relationship between the activities ,
provides project understanding and improves communications . The network is
constructed without considering the activity duration or the resource
requirement of the activity .
With the advent of computers , this stage has lost its earlier significance .
Now there are many softwares available , which provide the network if succeeding
activity/preceding activity lists are fed .
f. Calculation on Network : In this stage , the earliest start , the earliest
finish time , latest start time , latest finish time , critical activity
,optimization for time-cost , resource planning through the network , etc , are
carried out . We shall illustrate these calculations through examples .
Examples to be given
Project Control and project review : The planning is pre-construction activity .
The schedule of the project tells the project manager how to arrange the various
activities and what resources will be required at a particular instant of time ,
and how much progress is to be expected . During the construction phase , the
schedule serves as the yard-stick to check whether the project may be ahead of
plan or behind the plan . If it is behind , then network schedule also helps for
further resource mobilization .
Activity Time
In the network, it is important to know the criticality of the
activity, time available to perform the activity provided date of completion of
a project. In the previous section we have already talked about various method
of obtaining activity duration. We shall be interested in the question that
1. How early we can start the activity.
2. How much we can delay the activity
such that target date of completion of project is not affected
3. What the time available to perform the activity.
To answer the above question we shall associate (define) following time with an
activity
a)
Early start time b)
Early finish time c)
Latest start time
d)
Latest finish time
a) Early start time: Let
tij be the
earliest expected time
Earliest start time is

It is the earliest time by which an activity can started.
activity between events i and j. Let T E i
is the
of the event i then
equal is to
EST = T E i

b) Earliest finish time: The earliest finish time of an activity is the time by
which an activity can be finished earliest. The earliest finish time of an
activity is earliest start time plus activity duration.
EFT = EST + activity
duration
c) Latest finish time: The latest finish time is the time by which an activity
must be finished such that completion of the project is not delayed the latest
finish time of an activity between events i and j is the latest allowable event
time of
LFT= T Lj
d) Latest start Time: The latest start time is the time by which an activity
must start such that completion of project is not delayed. The latest start time
of an activity between events
i and j is latest finish time minus activity
duration.
LST = LFT – activity duration
Float: In the last reading we have discuss that in the project with art
interested in time available to execute particular task(activity) during the
project period. We shall introduce the concept float which tells us how much an
activity can fluctuate without affecting the completion of a project. We shall
introduce following float
a)
Total float.
b)
Free float. c)
Independent float.
d)
Interfering float. a)
Total float is the maximum time available
during which an activity can fluctuate. It is maximum time available minus
activity duration. The maximum time available in the difference between latest
finish time minus earliest start time.
Maximum time available to execute

the work = LFT – EST
Hence
total float = maximum time available – activity duration
= LFT – EST - t ij
= LST – EST
b)
Free float: - Free float is the time available to fluctuate the activity
without the affecting the succeeding activity. The mean of without affecting
succeeding activity is that the activity must finish before the earliest
occurrence of the head event.
Time available = T E i – EST
Free float = Time
available – activity duration
= T E i – EST - T E ij
Free float = T E i – EFT
c)
Independent float: - It is the time available to fluctuate if the
preceding activities get completed as late as possible and succeeding activities
get started as early as possible.
Hence time available = T E i – T Li
This is the minimum time available to execute
Independent float = Minimum time available – activity duration = T
E i – T Li - T E ij
d) Interfering float is defined as difference between total float and free
float.
Event
Event is the important point (mile stone) during execution of particular work or
task. Many a time we only are concerned about commencement or completion of the
task. Event is defined as start or end of an activity or activities. Thus, event
is followed by more than one activity. In this case event is marked
by completion of all activities or start of any one of the activity.
Example: 1. Start of plastering is an event.
2. Completion of excavation for piping
layout is an event.
3. Start of floor tiles is an event.
4. Giving power supply to fan and
light.
Event is characterized by completion and start of an activity. We can defined
a)
An event is said to occur if all the activity leading to it has been
completed.
b)
An event is said to occur if any of the activity has started.
During a project, project manager needs to know following two questions
a. How easily he can start any particular activity?
b. How late he can delay
such that project does not delayed?
We shall define following two times associated with an event.
a. Earliest expected time.
b. Latest allowable occurrence time.
Earliest expect time: The earliest expected time of an event is time which
tells the event can not occur earlier than this time.
If
is the expected occurrences time of an activity between event i and j and
and is the earliest occurrence time of the occurrence of this event then
earliest occurrence time of occurrence of the event j is related to that of
event i as = +
If there are many activities leading to the event j then earliest expected
time of j is =max( + ) for all i
The latest allowable occurrence time is the late occurrence of the event such
that schedule of the project is not disturbed. The time tells us how much the
event can be delayed such that project will be completed on time. Let us
consider an event i and j connected through activity i-j as
Let and
be the latest allowable occurrence time of event i and j. is the
expected time of activity i-j. Then the latest occurrence time of i is related
to the latest occurrence time of j as
= Thus we can see that latest allowable occurrence time of an event has to be
calculated starting from completion event of the project in backward direction.
This is called Backpass.

If suppose a number of activity starts from an event then the latest allowable
occurrence time is the minimum of the time calculated from all the path.
Earliest occurrence time and latest occurrence time is shown in the following
figureLet completion time of project is 32 days. The latest allowable occurrence time
is shown in box
The earliest expected time of an event is shown in box
Solved problems
Quality in Construction
Quality in construction is defined as ‘meeting or exceeding the requirement of
client/owners. In construction industry, quality is used in different every than
the product industry. In the product industry, quality of some product is better
than the other, but we can not say that one grade of concrete. Quality in
construction is employed with conformity with which specifications are met.
Designer specifies the grade of concrete to be used and contractor has to use
the in gradients of concrete such that desired grade of concrete is obtained.
Quality in construction is related to
satisfying the specification mentioned in the contract
completing the
project time.
Fulfilling the owner's requirement within budget
Avoiding disputes claims and
Ensuring the faculties performs its intended
purpose.
We use certain product in the construction industry such as tiles, brick.
Quality of these products can be partially related with the general connotation
of quality. Other aspect in quality has slightly different meaning at various
stages of life cycle of product such as at design stage or
construction stage.
Quality schemes involve economic studies of selection of types of
material and methods to be included in design , ensuring that this design is in
accordance with all applicable codes and regulation and controlling the
construction on the project to be sure that the work is performed according to
the standards specified in the contract documents . Method to be adopted may
vary from the automated documented through computer to statistical quality
control in the field .
Quality Assurance
Quality assurance is referred as a scheme adopted by a construction company to
maintain the standard or quality consistent. It is primarily an internal
management system of a construction company. Generally a company maintains a
quality assurance chart by specify various checks at different levels as well as
constantly improving its attributes. A quality assurance program may include
Arranging periodical training for its worker
a good safety Programme
a sound procurement system to get best quality
material and suppliers
A reward scheme for innovative work and competitive
career progress scheme
If a company is involved in repetitive work, then implementations of statistical
control of the process. Such as in concreting, regular sampling scheme control
the production of concrete. Similarly in asphalt work , regular satisfied
quality control is carried out.
Quality Control
Quality control is the periodic inspection to ensure that the constructed
facilities meet the standard specified in the contract. It is usually carried by
team of owners engineers or its morning. As for example, in a high way project,
engineers check that compaction of soil is carried out properly by measuring its
density; workability of concrete is checked by employing slump test etc. or
checking compressive strength of concrete at periodical level.
Quality assurance is good management scheme whereas quality control is an
inspection or sampling process.
Government works is generally carried out using lowest bid system. In lowest bid
system, high quality work carried out by contractor does not play a major role
rather price quoted by them is an important criteria.
The procedure for selection of contractor affects the quality control in the

construction. Low bid system hardly provides any incentive to high quality work
carried out by the contractor. Government organizations are highly their hard to
improve the low bid system.
Quality control includes
a. Setting up specific standard for construction
b. Checking the deviation
from the standard
c. Taking action to correct or minimize the variation
d. Improvement of
the standard.
Quality Standardization
ISO 9000 standards fix the standard for quality. ISO stands for International
organization for standardization. This organization founded in Switzerland in
1947. Similar standards for Indian context are IS 14000 – 04.
ISO 9000 series of standard are quality assurance standard that assures client
that the organization having obtained the certification works according to
specified requirement.
It stands for system standardization and certification. Emphasis is given to
defining and laying down the procedure, process etc in the form of documents.
ISO is important because it offers an internationally recognized systematic
approach, coupled with institutionalization of the institutes, policies,
procedures, record keeping, technologies and resources for managing quality
work.
Basic principles advocated by ISO are a. Focus on customer
b. Provide leadership
c. Involve your people
d.
Use a process approach
e. Take a systematic approach
f. Encourage
continual improvement
g. Get the facts before you decide
h. Work with your supplier
ISO 9000 series standards are – ISO 9000 ISO 9001
ISO 9002 ISO 9003 ISO 9004
Elements of Quality
The basic element of quality in construction is
a)
Quality characteristics b)
Quality of design c)
Quality
of conformance
a)
Quality characteristics is related to the parameters with respect to
which quality – control processes are judged. Quality characteristic includes
strength, colors, texture, dimension, height etc. Example in compressive
strength of concrete, usability of concrete in slump , etc.
b)
Quality of design:- It refers to the quality with which the design is
carried out. It primarily related to meeting the requirement of the standard,
functionally efficient system and economical maintainable system.
c)
Quality of conformance:- It is referred to the degree to which the
constructed facility conformed the design and specification. Quality of
conformance is affected byi. field construction methodology ii. Supervision
iii. Inspection
Economics of Quality of design
Quality of design is generally evaluated based on economics of quality. There
are two aspects of economics of quality design
a. value addition of quality
b. cost of quality
With the increase of quality of design, dost increase is exponential but value
addition initially increases, but starts saturating at of some point. Hence the
optimum cost is arrived when slope of both the curves is same .
The economics of quality conformance is shown in the figure. One can note that
with the increase of quality of construction, cost of quality control gets
saturated. Thus we can arrive at optimum quality for minimum cost from total
cost of the construction. This has been shown in the figure .
IS Code provision for quality control of concrete
IS 456 provides the
schemes for quality control and quality assurance of concrete , we have
reproduced the clauses –
Clause 10.1 Quality Assurance Measures
Clause 10.1.1 In order that the properties of the completed structure be
consistent with the requirements and the assumptions made during the planning
and the design, adequate quality assurance measures shall be taken. The
construction should result in satisfactory strength, serviceability and long

term durability so as to lower the overall life-cycle cost. Quality assurance in
construction activity relates to proper design, use of adequate materials and
components to be supplied by the producers, proper workmanship in the execution
of works by the contractor and ultimately proper care during the use of
structure including timely maintenance and repair by the owner.
Clause 10.1.2 Quality assurance measures are both technical and
organizational. Some common cases should be specified in a general Quality
Assurance Plan which shall identify the key elements necessary to provide
fitness of the structure and the means by which they are to be provided and
measured with the overall purpose to provide confidence that the realized
project will work satisfactorily in service fulfilling intended needs. The job
of quality control and quality assurance would involve quality audit of both the
inputs as well as the outputs. Inputs are in the form of materials for concrete;
workmanship in all stages of batching, mixing, transportation, placing,
compaction and curing; and the related plant, machinery and equipments ;
resulting in the output in the form of concrete in place. To ensure proper
performance, it is necessary that each step in concreting, which will be
covered, by the next step is inspected as the work proceeds (see also 17).
15.1.1 In order to get a relatively quicker idea of the quality of concrete,
optional tests on beams for modulus of rupture at 72 + 2 h or at 7 days, or
compressive strength tests at 7 days may be carried out in addition to 28 days
compressive strength test.
For this purpose the values should be arrived at based on actual testing. In all
cases, the 28 days compressive strength specified in Table 2 shall alone be the
criterion for acceptance or rejection of the concrete.
15.2 Frequency of Sampling
15.2.1 Sampling Procedure
A random sampling procedure shall be adopted to ensure that each concrete batch
shall have a reasonable chance of being tested that is, the sampling should be
spread over the entire period of concreting and cover all mixing units.
15.2.2 Frequency
The minimum frequency of sampling of concrete of each grade shall be in
accordance with the following:
Quantity of Concrete in the Number of Samples
Quantity of Concrete in the work , m 3 No of samples
1-5 1 6-15 2 16-30 3 31-50 4 51 and above 4 plus one additional sample
for each additional 50 m 3 or part thereof
NOTE - At least one sample shall be taken from each shift where concrete is
produced at continuous production unit, such as ready-mixed concrete plant,
suppliers and purchasers may agree upon frequency of sampling mutually by
suppliers and purchasers.
Total Quality Management ( TQM )
Total quality management(TQM) is a system of
continuously improving goods or services . The philosophy was promoted by W.
Edwards Deming . A TQM approach is considered as essential to long term survival
of the business , such as construction . In the TQM philosophy , everyone in the
company should feel involved and committed for quality of products , from top to
bottom of the organization . Total quality management provides principles ,
tools and techniques for cultural changes and continuous improvement . Quality
assurance can be considered as part of Total Quality Management . Basically
quality assurance is a system of approach which is related to attitudes and
working environment of the company . Deming has suggested 14 points for total
quality management which are –
1. create constant commitment to the employee for aim and purpose of the company
and improvement .
2. Adopt new philosophy to avoid defects .
3. Use
statistical quality control and understand purpose of inspection .
4. Practice of business should be based on statistical evidence rather than
price tag alone .
5. Improve constantly and forever production and services .
6. Employee training .
7. Teach and institute leadership .
8. Encourage
communication and productivity .
9. Encourage teamwork, to work in group .
10. Eliminate posters or slogans with specific improvement methods .
11.

Use statistical methods to continuously improve quality and productivity .
12. Remove barriers that rob people of pride of workmanship.
13. Provide
education and self improvement for everybody .
14. Define top management
commitment for quality .
The basic foundation for total quality management is –
Everyone in the company should understand the mission and vision of the business
.
Total management should be highly committed to quality . Continuous training is
required .
Commonly used equipments for the excavation are –
1. Bulldozers 2. Power Shovels
3. Scrapers 4. Dragline 5. ClamShell 6.
Backhoe
1. Bulldozers – A dozer which is popularly called bulldozer is a self contained
tractor power unit with a blade attached to its front . The are used for pushing
the materials , land clearing , striping , towing other pieces of
constructions , assisting in loading side hill cutting , backfilling & spreading
, etc . The amount of material a dozer can move depends upon the size of the
blade , tha is the amount of material that can remain in the blade .
Dozers can be classified as – a. Crawler type b. Wheel type
Dozers are generally used for haulage distances less than 50m .
2. Power shovels - Shovels also called power shovels are the hydraulic
excavator . In the shovel , a excavation bucket is attached to the hydraulically
controlled boom & stick . The bucket moves in a forward and upward direction .
The bucket can be swung around depending upon the type of the shovel and load
the soil in the truck. The shovels may be either crawler or rubber tire carrier
mounted . They are many variations , depending upon the manufacturers. Its
capacity is dependent upon the manufacturer specifications . A construction
engineer needs to enquire about the bucket capacity , cutting height , output ,
etc to plan the construction work .
3. Scrapers – Scrapers is a large steel bowel attached with the cutter at the
bottom , which is molded on the wheel. It is a multipurpose equipment which is
used for excavation the soil , transporting it and spreading it at the other
place . The basic operating parts of the scrapers are bowl , apron, ejector .
During excavation , the cutting edge is lowered to scrape the soil . the cutting
edge is raised when the bowl is filled . The material is spread after
transporting a short distance . There are various types of scrapers , such as
pusher loaded , self loading , etc . Scrapers can be used for a haulage distance
of 100m to 1500m . Scrapers are not suited for hard rock , muddy soil and
certain types of sands which does not pile up in the scrapers .
4. Dragline – In a dragline , a bucket is connected to a cable , which is
attached to a long -___________ crane . The soil is excavated by dragging this
bucket against the soil to be excavated . In dragline , bucket falls under the
gravity load which loosens the soil . It is used for excavation as well as
loading the material in the truck . Dragline can also be used for underwater
excavation .
5. Clamshell – Like dragline , clamshell bucket is designed to excavate the soil
in vertical direction . The bucked is like an inverted jaw , having a biting
motion . Generally it is used for excavating soft soil and stockpiling it . The
bucket can be opened and closed with the help of a cable or by hydraulic control
. It is designed in such away that it is half opened when dropped and gets
closed when the bucket is filled . it can stock pile the soil up to 20-30m of
height and at a diameter up to 60m . It is often used in mining industry .
6. Backhoe – Backhoe is hydraulic excavator with a bucked attached to hydraulic
controlled boom and stick . In backhoe , the excavation bucket moves in downward
and backward direction during excavation . The difference between power shovel
and backhoe is the movement of bucket . Backhoe may be crawler or rubber wheel
mounted . Backhoe is more suited for the excavation below the ground , such as

excavation for basements in building construction or trenches for laying sewer
lines . The learning requirements for backhoe is same as power shovel .
Transportation
We have seen that some of the equipments used for excavation are also used for
transporting for a distance , depending upon ground conditions . Many a time ,
the soil needs to be transported to other places which are not adjacent to the
excavation site. The equipment used for transportation is also called haulers .
Various equipments used for transportation are –
a. Belt conveyers b. Tippers c. Truck d. Dumpers e. Graders
Trucks are used for small quality of earthwork which is loaded manually .
Tippers generally unload by rear-tipping . Dumper is basically a truck with
large size with self unloading mechanisms via hydraulic pump . Conveyers are
used in the terrain where transportation is a problem .But it has larger
installation cost and generally is used in the place where large quantity of
soil has to be hauled . A Grader is a wheel mounted tractor unit used to
spread , trim and level soil with very high precision . This is widely used in
road construction for leveling and maintaining the grade .
Compaction
After excavated soil has been transported and spread at the desired places , it
is compacted to obtain the desired density . the optimum density is obtained on
a certain moisture content of the soil . Generally , the right amount of water
is mixed before compaction the soil . For different types of soil , different
compaction equipments are used . A single equipment is not effective for all
types of soil . A roller compacts the –
Pressure Kneading Vibration
Impact
Various compaction equipments are a. Smooth wheel roller
b. Pneumatic tired roller c. Sheep foot roller d.
Vibratory roller equipment –
i. i. Dropping weight type
ii. Pulsating hydraulic type .
a. Smooth wheel roller – Smooth wheel roller compacts the soil by applying
pressure on it . It is used for coarse grained soil and spread in thin layer .
For find grained soil , they are not effective . These rollers are only useful
in smoothing the upper layer , whereas bottom layer normally remains loose .
b. Pneumatic tired roller – Pneumatic tired roller used the principle of
___________ action to effect the compaction below the surface . They are
generally self – propelled . The rear tires are spaced in such a way they travel
over the surfaces between the front tires . Thus the roller produces compaction
of the whole surface . The parameters which determine the compacting ability of
pneumatic rollers are –
i. Wheel load ii. Tire size iii. Tire ply
iv. Inflation pressure
There are pneumatic rollers which have the capacity to increase its tire
pressure during compaction . Initial compaction is carried out with low pressure
. The roller increased its tire pressure in subsequent operations . They are
used for fine grained soil .
3. Sheep foot roller – Sheep foot rollers are steel wgeaks equipment with
protuded cylindrical projection of 20-25cm. They are suitable for compacting
fine grained material , but generally is not suited for cohesionless granular
material . They compact the soil kneading type of action . These rollers are
helpful in breaking the lumps or clods present in the soil . These rollers
aerates the soil during compaction . Thus , they are suitable for compaction
soil heavy in moisture content above the optimum level .
4. Vibratory Compaction equipments – Vibratory rollers compact the soil through
impact forces . These forces result in compaction greater than the equivalent
static load . Vibratory rollers are suitable for coarse grained soil . These
rollers may be pulsating weight type . Plate compactors are widely used in the
building construction for compacting soil in the room . Power tamper is a drop
weight type vibrating compactor . Vibratory roller can be pad tool type.
Vibratory rollers can be used for all types of soil except for plastic clays .

Remarks – There are many variations of the compacting equipments ; we have
mentioned the important characteristics . A construction engineer needs to know
The suitability for a particular type of soil
1. Capacity of the roller
2. Efficiency of the various rollers
These parameters help him in the selection of the proper compacting equipment
During earthwork following volume measurements are used –
1. Bank measure volume
2. Loose measure volume
3. Compacted volume
1. Bank measure volume – the volume of earth measured prior to excavation is
called bank measure volume .
2. Loose measure volume – This is the volume of excavated soil . This volume
is useful for transportation payment .
3. Compacted volume – This is the volume of earth after the compaction .
Suppose certain areas are to be filled up , we have to specify the compacted
density . This volume will be useful in this payment .
Drilling :
Making a hole in rock or earth is called drilling. It is a very
ancient human construction activity. The process of a man swinging a hammer
against a point drill is as old as civilization. Drilling is an important
construction activity which is required for following purposes To explore the types of materials to be encountered on a project usually called
exploratory drilling.
For explosive charges
For grouting on rock bolt stabilization
Making
bore for placing utility lines
Seep hole for drainage of water
Constructing well for water supplies
For obtaining sample of soil for testing
Installing cast in-site piles
Driving shaft for ventilating tunnels and other
underground facility
Making horizontal holes to install various utilities
Locating deposits of aggregates
Drilling is a very fundamental activity in mining and petroleum industry. We
shall confine our self here to give an introductory view of drilling as used in
the construction industry. Different methods and equipments are used for
drilling in rock and earth drilling. The factor affecting the selection of
equipment can be enumerated as The required depth of the holes The size of project The purpose of drilling
Type of terrain
The size cores required for exploration
The nature of the formation i.e. extent to which it is broken or fractured
Drilling equipments can be categorized into the following broad groups a. Percussion drills
b. Rotary drills - The rotary drills can be further
grouped into i. Pressure drilling
ii. Abrasion drilling
Also, various types of augers are used for earth drilling.
a. Percussion drilling - A percussion drill breaks rocks into pieces by the
impact from repeated blows. Sometimes, compressed air or hydraulic fluid can
power percussion drills. It may be combined as rotary and percussion. It
generally employs a reciprocating air operated hammer with impacts a rotating
bit or a spring of rotating drill with bit on its bottom.
b. Rotary drilling - In the rotary drilling, the drilling is carried by applying
a down pressure and at the same time continuously rotating the bit in the hole.
This type of drills can be mounted on a truck or crawler tracts. These drills
are suitable for drilling soft or medium rock.
Blasting
The operation to break rocks such that it can be quarried for processing
aggregate production or to excavate a right-of-way is called blasting. Blasting
is carried out by discharging an explosive in the borehole or any other confined
manner carries out blasting. There are various types of commercially available
explosives. They can be i. Dynamite ii. Slurries iii. ANFO, or iv. Two components explosive
The various issues involved in the blasting can be listed as follows a. A site engineer should understand the process of blasting. Depending on the

type of explosives, the blasting process has been developed. A site engineer
should understand different components in the blasting process.
b. The understanding of the nature of explosive is very important. He has to
know the various materials available in the market. Economy and suitability of
the explosive for the particular site condition plays an important role.
c. The site engineer should make safety plan during blasting. Each member of
his team should understand the safety requirements.
d. Transportation and storage of explosives is very dangerous. The
explosive should be transported and stored with high safety.
e. The schedule of blasting should be intimated to the local people residing in
the areas near to the site.
Tunneling
Tunnels are horizontal underground passages generally used for transporting men
and materials. Making caves and tunnels is a very old activity of mankind, which
even dates back to 4000 B.C. In the present day, tunnels are used for the
following purposes Underground traffic
Diversion of river water
Water supply and drainage
Excavation of precious materials such as coal,
iron, gold.
Military purposes like underground fortification
Underground power plant, warehouse
For underground parking places
Subways and express ways
Tunnels are generally of a few metres to several kilometers. Its diameter ranges
from that of less than a metre to 16-17metres. It may be near to the ground or
may be at large depths below the ground surface, such as those tunnels in
mountains. Before starting the tunneling work (process of making a tunnel),
following investigations should be carried out meticulously a. Hydrological
survey
b. Geological survey and exploration
c. Rock temperature and gases
d. Factor influencing the depth of the tunnel below the ground level
e.
Factor affecting the diameter of the tunnel
f. Geological features along the axis of the tunnel
The above factors are important for arriving at the design of the tunnel, but a
site engineer has to investigate the parameters before design. Also, a
construction engineer should always verify the available data for design. If
there is any discrepancy in the existing profile with the coordination during
design of a tunnel, modifications are needed.
Tunneling is carried out by a. Cut and cover tunneling
b. Bored tunneling
a. Cut and cover tunneling - Generally, cut and cover tunneling is carried out
at the shallow depths. In this process ground is excavated and a concrete box is
casted, and then it is covered with the soil. The process of cut and cover
tunneling is shown in the figures on the next slides b. Bored tunneling – In the case of soft soil, a shield is used before
excavating the soil. In rocks, rocks are drilled and blasted. Depending on the
method used, the tunneling process can be described asi. Full face heading
ii. Heading and bench method
iii. Ring Drilling
method
iv. Groove method
v. Side Drift method
In the full-face heading, the entire face is drilled and blasted in one
operation. This method is economical, speedy and most widely used. In the
heading and bench method, the top portion is blasted after drilling and loading.
Lower portion is treated as one or more benches and drilled as well or blasted
horizontally or vertically.
There are various shield mechanisms, which are used. Some of them are
illustrated in the following slides Piling
Depending upon the purpose for which piles are used, they can be grouped as -

a. Load bearing pile
b. Sheet pile
Load bearing piles are used to transfer the load of super structures to ground
whereas sheet piles are lateral support of earth during excavation. We shall
talk about the various issues related to the construction of piles. We shall
confine ourselves to only the popularly used piles and construction methods.
Indian Standard IS 2911 specifies the following four types of piles a. Driven cast-in place pile
b. Bored cast in piles
c. Pre-cast driven
piles
d. Pre-cast driven in pre-bored piles
The Indian standard IS 2911 also gives the specification for Timber piles and
under reamed piles. The driven piles are displacements piles whereas bored piles
are non-displacement piles. Depending upon the diameter of the piles, they are a. Large diameter piles - greater than 600mm
b. Small diameter piles - 300mm
to 600mm c. Mini piles - 150mm to 250mm
d. Micro piles - less than 150mm
During the installation of piles, the construction engineers have to keep in
mind the following points a. Pile driving causes disturbances to the surrounding areas. The noise of
hammering is very troublesome.
b. When pre-cast or cast-in-place piles are driven in soil, a volume equal
to the volume of penetration of the pile is displaced. If the pore water
pressure is not dissipated, then ground heave takes place because there will not
be a volume change.
c. If the pre-cast driven pile is installed in the hard soil, it tends to
set damage due to driving stresses and at the top due to lack of strength or
lack of proper equipments.
d. Bored piles require proper washing of the base of the pile. It depends
upon the availability of proper equipment, workmen and experienced contractors.
e. Generally, time taken for installation of driven pile (both cast-inplace and pre-case) is faster than bored pile.
f. If has been found to be difficult to pull out the casing after
concreting while using driven cast-in-place pile in pure sand deposits.
g. Dumping of concrete from large height in cast-in-place pile particularly
in driven piles cause segregation of concrete. A special care is needed to avoid
them.
h. The ground surface should be made such that the equipment should be
able to move freely. After the piling, driven piles remain projected above the
ground level. This may cause inconvenience in the movement of equipment
backwards.
i. The bituminous coatings on the surface of pre-cast piles reduce the negative
skin friction.
c. If the pre-cast driven pile is installed in the hard soil, it tends to
set damage due to driving stresses and at the top due to lack of strength or
lack of proper equipments.
d. Bored piles require proper washing of the base of the pile. It depends
upon the availability of proper equipment, workmen and experienced contractors.
e. Generally, time taken for installation of driven pile (both cast-inplace and pre-case) is faster than bored pile.
f. If has been found to be difficult to pull out the casing after
concreting while using driven cast-in-place pile in pure sand deposits.
g. Dumping of concrete from large height in cast-in-place pile particularly
in driven piles cause segregation of concrete. A special care is needed to avoid
them.
h. The ground surface should be made such that the equipment should be
able to move freely. After the piling, driven piles remain projected above the
ground level. This may cause inconvenience in the movement of equipment
backwards.
i. The bituminous coatings on the surface of pre-cast piles reduce the
negative skin friction.
j. According to the Indian Standard IS 2911 (Part 1 Section 3), negative
skin friction developed as in the following cases. Special care is needed.
i. For Pile in clay strata which is subjected to shrinkage settlement
ii. Lower of ground table causes settlement of ground causing negative
skin friction.

iii. Fill ground undergoes consolidation which causes negative skin
friction.
iv. Negative skin friction develops if soil sets re-moulded or disturbed
due to the pile installation
v. If pile is installed in clayey soil with surcharge loading, negative
skin friction may develop.
Whenever there is a chance of settlement of soil and clay soft layer is
encountered, negative skin friction may get developed. It is required to take
special care whenever there is a chance of development of negative skin
friction.
Pile Driving Equipments
Pre-cast pile driving equipments consist of 1. Pile frame
2. Pile hammer 3. Helmet 4. Follower
1. Pile frame - Pile frame is a frame mounted on crawlers or trucks having
arrangement of lifting, aligning and driving the pile.
Figure To Be Given
2. Pile hammer - There are different types of hammers used which are i. Prop
hammer ii. Vibratory hammer iii. Single action hammer
iv. Double action
hammer
v. Diesel hammer
In India, drop hammers are widely used.
3. Helmet - It is assembly to avoid damage of the pile from hammer. Helmet
consists of cushion, steel cap and dolley.
4. Follower - Follower is generally used when pile is out of reach of
hammer. It is the extension, which transmits hammer blows to the piles.
Selection of pile hammers
The following pile hammers are more efficient than the drop hammers
a. Single acting steam or compressed air hammer
b. Double acting steam or compressed air hammer
c. Diesel hammer - Diesel hammer is used when hard driving is required.
The capacity of hammer is calculated based on the depth to which the file should
penetrate.
How to maintain nominal cover in concrete piles
How to construct a bored pile
Dewatering
There are many situations when construction is to be carried out below the
ground water table. In such circumstances, excavation becomes very difficult.
Either seeped water has to be pumped or the water table has to be lowered. The
process of lowering the water table is called dewatering . Sometimes, we use the
term pumping and dewatering together. There are many ways that the dewatering
can be carried out. These can be classified as a. By pumping the collected water in the sump
b. By pumping water from
suitably arranged well points
c. By pumping water from suitable arranged bored wells
a. By pumping the collected water in the sump - This method is commonly used in
the construction where there aren't any important structures close to the
excavated area and enough area is available to maintain a stable slope. In this
method, one or more sumps are made at the outer boundary of the excavated site
and cutting ditches around the bottom of the excavation collects water. This
open sump method is generally used for construction not more that 6-7m below the
water table. This method is less costly, but there are limitations. If there is
fine sand lying below the water table, they get removed in seeping and causes
settlement of the surrounding area. The process of open sump pumping is
illustrated for foundation.
5. Excavate the soil above the water table and make the ditch and sump, in a
similar manner as in step-3 and pump the water. Repeat this process till
excavation is complete up to desirable depth.
Note: Sand gravel layer is provided at the base which acts as a filter and keep
the working area dry.
b. Suitably arranging the well point- In this method, the concept of
lowering of the water table surrounding the well point is used to lower the
water at the construction site. The figure (a) and (b) show the draw down curve

for single and multiple well points. Fig(a)
Fib(b) Well points are arranged around the area for construction at a distance
of 1 to 4m.These well points can be arranged in single stage as shown in figure
(c) or double stage as shown in figure (d).
c. Suitable arranging the
bored wells - Bored wells are generally used when the water table has to be
lowered beyond 15m. In this method, well is bored in the ground at a distance of
5m to 40m, depending upon the soil condition. Pumps are installed at this water
table level. A typical well is shown in the figure.
This method also works in a similar way as well points. Bored well are arranged
around the excavated site, in a single chain, similar to single stage well
points.
Commonly used pumps in construction industry arei. Reciprocating pump
ii.
Diphagram pump
iii. Conventional centrifugal pump
iv. Self primary
centrifugal pump
v. Air operated centrifugal pump