The document outlines a comprehensive course on engineering project management, detailing expectations for students and key topics such as construction scheduling techniques, project control, and the critical path method (CPM). It defines project management, highlights the importance of effective scheduling, and discusses the elements necessary for successful water resources management. Various project management tools including bar charts, networks, and critical path analysis are also emphasized to aid in planning and execution.

1. Biniam Zewdie G/Kidan *
•Haramaya Institute of University
P.O.Box:138; Dire Dawa, Ethiopia
•Mobile: +251910408218/+25191582832
•E-mail: nzg2001nzg@gmail.com/zewdienico@gmail.com

2. Engineering Project
Management
Department Agricultural Engineering (AGEN)
&
Department Water Resource and Irrigation Engineering(WRIE)

3. 3
Your Expectations of Me
Be prepared
Be on time
Teach for full 50 minute period
Fair grading system
Front load the class work
Do not humiliate students
Practice golden rule
Provide real world examples
Make you think

4. 4
Topics
1) Management Functions and introduction of construction
project planning and scheduling
2) Construction scheduling techniques
3) Preparation and usage of bar charts
4)Preparation and usage of the Critical Path Method (CPM)
5)Preparation and usage of Precedence Diagramming Method
(PDM)
6)Issues relating to determination of activity duration
7)Contractual provisions relating to project schedules
8)Resource leveling and constraining
9)Time cost tradeoff
10)Schedule monitoring and updating.
11)Communicating schedule
12) Project control and earned value Control
13) claims, Safety and Quality control
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Course Outline
Introduction and definitions Float Analysis
Importance of Scheduling The CPM Calculations
Networks, Bar Charts, and Brief introduction on:
Imposed Finish Date and Project Control and Earned
Value Analysis Resource Allocation /Leveling
other CPM Issues Time/Cost Trade-off
Precedence Networks
Updating Schedules
Time-Scaled Logic Diagrams
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In order to understand project management, one must
begin with the definition of a project. A project can be
considered to be any series of activities and tasks that :.
● Have a specific objective to be completed within certain
specifications
● Have defined start and end dates
● Have funding limits (if applicable)
● Consume human and nonhuman resources (i.e., money,
people, equipment)
● Are multifunctional (i.e., cut across several functional
lines)
What is the Project
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OR
‘‘a temporary endeavor undertaken to create
a unique product, service, or result’’
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Table 1-1. Comparative Overview of Project, Program, and Portfolio Management

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Objectives of Water Resources Management
The goal of the water resources management is sustainable
water use.
In order to achieve the effective and sustainable water
resources management, items which shall be required for the
proper monitoring, evaluating and controlling works are
summarized as follows;
a) Water quantity
b) Water quality
c) Hydro-meteorological and hydro-geological network
d) Drought management
(Reservoir operation/ Water diversion)
e) Watershed management
(Drainage water regulation/Forest protection/Land
conservation)
f) Facilities maintenance

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Project Life
Cycle

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Five Process group
Project initiation
● Selection of the best project
given resource limits
● Recognizing the benefits of
the project
● Preparation of the
documents to sanction the
project
● Assigning of the project manager
Project planning
● Definition of the work
requirements
● Definition of the quality and
quantity of work
● Definition of the resources needed
● Scheduling the activities
● Evaluation of the various risks
Project execution
● Negotiating for the project
team members
● Directing and managing the
work
● Working with the team
members to help them improve
Project monitoring and control
● Tracking progress
● Comparing actual outcome to
predicted outcome
● Analyzing variances and
impacts
● Making adjustments
Project closure
● Verifying that all of the work has
been accomplished
● Contractual closure of the contract
● Financial closure of the charge
numbers
● Administrative closure of the paper
work
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Successful project management can then be defined as
having achieved the project objectives:
● Within Time
● Within Cost
● At the desired performance/Technology level
● While utilizing the assigned resources effectively
and efficiently
● Accepted by the customer
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What is Project Management
Project management is the planning, organizing, directing,
and controlling of company resources for a relatively
short-term objective that has been established to complete
specific goals and objectives.
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The potential benefits from project
management are:
● Identification of functional responsibilities
● Minimizing the need for continuous reporting
● Identification of time limits for scheduling
● Identification of a methodology for
trade-off analysis.
● Measurement of accomplishment
against plans
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The above definition requires further comment. Classical
management is usually considered to have five functions
or principles:
● Planning
● Organizing
● Staffing
● Controlling
● Directing
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Planning
– Where the organization wants to be in the
future and how to get there.
Organizing
– Follows planning and reflects how the
organization tries to accomplish the plan.
– Involves the assignment of tasks, grouping of
tasks into departments, and allocation of resources.
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Leading
– The use of influence to motivate employees to
achieve the organization's goals.
– Creating a shared culture and values,
communicating goals to employees throughout
the organization, and infusing employees to
perform at a high level.
Controlling
– Monitoring employees' activities, determining if
the organization is on target toward its goals, and
making corrections as necessary
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Conceptual Skill—the ability to see the
organization as a whole and the relationship
between its parts.
Human Skill—The ability to work with and
through people.
Technical Skill—Mastery of specific
functions and specialized knowledge
Management Skills
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Project management is designed to manage or control
company resources on a given activity, within time, within
cost, and within performance. Time, cost, and performance
are the constraints on the project.
Constraints of the project
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Resources
We have stated that the project manager must control company
resources within time, cost, and performance. Most companies have
six resources:
● Money
● Manpower
● Equipment
● Facilities
● Materials
● Information/technology
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Actually, the project manager does not control
any of these resources directly, except perhaps
money (i.e., the project budget).
Resources are controlled by the line managers .
The project manager is responsible for
coordinating and integrating activities across
multiple, functional lines. The integration
activities performed by the project manager
include:
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● Integrating the activities necessary to develop a project plan
● Integrating the activities necessary to execute the plan
● Integrating the activities necessary to make changes to the plan
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41. Monitoring versus Evaluation
Monitoring
• Data collected on
program activities
• Ongoing, routine
• Focus on activities and
output, compared to
target
Are we doing the work
we planned?
Evaluation
• Data collected to answer
specific questions
• Periodic
• Focus on outcome,
impact
How effective were our
activities?

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Project Scheduling Planning,
Scheduling, and Control
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Planning and Scheduling
Planning and scheduling are two terms that are
often thought of as synonymous
 They are not!
 Scheduling is just one part of the planning effort.
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 Project planning serves as a foundation for several
related functions such as cost estimating, scheduling,
and project control.
 Project scheduling is the determination of the
timing and sequence of operations in the project
and their assembly to give the overall completion
time
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Planning is the process of determining how a
project will be undertaken. It answers the
questions:
1. “What” is going to be done,
2. “how”,
3. “where”,
4. By “whom”, and
5. “when” (in general terms: start and finish).
Scheduling deals with “when” on a detailed
level… See Figure 1 .
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The Plan
What
How
much
By
whom
where
Why
How
when
Figure 1 . Planning and Scheduling
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The Plan
PMI defines project management plan as a ‘‘formal,
approved document that defines how the project is executed,
monitored and controlled”.
The plan can include elements that has to do with
scope, design and alternate designs, cost, time,
finance, land, procurement, operations, etc.
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WHY SCHEDUALE PROJECTS ?
1- To calculate the project completion.
2- To calculate the start or end of a specific activity.
3-To expose and adjust conflict between trades or
subcontractor.
4- To predict and calculate the cash flow .
5-To evaluate the effect of changing orders ‘CH’ .
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6- To improve work efficiency.
7- To resolve delay claims , this is important in
critical path method ‘CPM’ discussed later..
8- To serve as an effective project control tool .
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The Tripod of Good Scheduling System
1. The Human Factor : A proficient scheduler or
scheduling team.
2. The Technology : A good scheduling computer
system (software and hardware)
3. The Management : A dynamic, responsive, and
supportive management.
 If anyone of the above three ‘‘legs’’ is missing, the system
will fail.
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Scheduling and project management
Planning, scheduling, and project control are extremely
important components of project management.
project management includes other components :
• cost estimating and management,
• procurement,
• project/contract administration,
• quality management,
• and safety management.
 These components are all interrelated in different ways.
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Bar (Gantt) Charts
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DEFINITION AND INTRODUCTION
• A bar chart is ‘‘a graphic representation of project
activities, shown in a time-scaled bar line with no
links shown between activities’’
 The bar may not indicate continuous work from
the start of the activity until its end.
or
 Non continuous (dashed) bars are sometimes
used to distinguish between real work (solid line)
and inactive periods (gaps between solid lines)
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• Before a bar chart can be constructed for a
project, the project must be broken into
smaller, usually homogeneous components,
each of which is called an activity, or a task.
Item Activity
M 10 Mobilization
Bars ( Month or Year )
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ADVANTAGES OF BAR CHARTS
1- Time-scaled
2- Simple to prepare
3- Can be more effective and efficient if CPM based
- Still the most popular method
4- Bars can be dashed to indicate work stoppage.
5- Can be loaded with other information (budget,
man hours, resources, etc.)
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Bar Charts Loaded with More Info.
Such as : budget, man hours and resources .
10 12 7 11 10 9 15
500$
220$
400$
850$
140$
500$
900$
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DISADVANTAGES OF BAR CHARTS
1- Does not show logic
2- Not practical for projects with too many
activities
- As a remedy, we can use bar charts to show:
1. A small group of the activities (subset)
2. Summary schedules
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Basic Networks
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DEFINITION AND INTRODUCTION
• A network is a logical and chronological graphic
representation of the activities (and events)
composing a project.
• Network diagrams are the preferred technique for
showing activity sequencing.
• Two main formats are the arrow and precedence
diagramming methods.
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Two classic formats
AOA: Activity on Arrow
AON: Activity on Node
Each task labeled with
Identifier (usually a letter/code)
Duration (in std. unit like days)
There are other variations of labeling
There is 1 start & 1 end event
Time goes from left to right
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Arrow Diagramming Method (ADM)
1. Also called activity-on-arrow (AOA) network
diagram or (I-J) method (because activities are
defined by the form node, I, and the to node, J)
2. Activities are represented by arrows.
3. Nodes or circles are the starting and ending
points of activities.
4. Can only show finish-to-start dependencies.
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i j
(a) Basic Activity
Activity Name
Node (Event) i
j > i
Each activity should have a unique i – j value
Node (Event) j
Basic Logic Patterns for Arrow Diagrams
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2
A
(b) Independent Activities
4 10
B
12
3 A
6 B
9
(c) Dependent Activities
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2
A
(d) A Merge
4
6
B 8
(e) A Burst
C
Activity C depends upon the completion of both Activities A & B
8
A
6
2
B
4
C
Activities B and C both depend upon the completion of Activity A
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(f) A Cross
20
18
C
16 D
14
A
12
B
Activities C and D both depend upon the completion of Activities A and B
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Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B
D
C,D
E
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Solution :
10
30
40
20 50
C
D
A
B
E
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Dummy activity (fictitious)
* Used to maintain unique numbering of activities.
* Used to complete logic, duration of “0”
* The use of dummy to maintain unique numbering of
activities.
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4 10
4 10
11
A
B
A
B
Divide node to correct
Dummy
(a) Incorrect Representation
(b) Correct Representation
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Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B,C
D
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71. 71
10 30
20 40
C
D
A
B
Solution :
10
30
40
20 50
C
D
A
B
Dummy
Improper solution
proper solution
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72
72
Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B
D
B,C
E
C
F
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Solution :
10
30
40
20 60
C
E
A
B
Dummy 1
50
Dummy 2
D
F
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Removal of Redundant Dummies
A
A
A
A
B
B
B
B
C C
Original Diagram Diagram after removal
of redundant dummies
(a)
(b)
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A
A
A
A
C
C
B
C
B B
Original Diagram Diagram after removal
of redundant dummies
(c)
(d)
B E
C
E
E E
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Immediately Preceding
Activity (IPA)
Depends Upon
Activity
-----
A
B
-----
A
A, B
A
B
C
B C
A
Redundant
Relationship
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Activity List with Dependencies:
Depends Upon
Description
Activity
-----
-----
A
A, B, C
A, B, C
B, C, J, M
B, C, D, E, K
D, E, F, G, L
-----
-----
-----
-----
Site Clearing
Removal of Trees
Excavation for Foundations
Site Grading
Excavation for Utility Trenches
Placing formwork & Reinforcement
Installing sewer lines
Pouring concrete
Obtain formwork & reinforcing steel
Obtain sewer lines
Obtain concrete
Steelworker availability
A
B
C
D
E
F
G
H
J
K
L
M
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Depends Upon
Description
Activity
-----
-----
A
A, B, C
A, B, C
B, C, J, M
B, C, D, E, K
D, E, F, G, L
-----
-----
-----
-----
Site Clearing
Removal of Trees
Excavation for Foundations
Site Grading
Excavation for Utility Trenches
Placing formwork & Reinforcement
Installing sewer lines
Pouring concrete
Obtain formwork & reinforcing steel
Obtain sewer lines
Obtain concrete
Steelworker availability
A
B
C
D
E
F
G
H
J
K
L
M
Removing Redundant Relationships:
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AOA Representation
H
40
G
45
C
F
D
35
15
10
5
B
A
20
M
25
J
30
E
L
K
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NODE NETWORKS MTHOD (AON)
a) Independent Activities
10
A
20
B
Activity number
Activity name
b) Dependent Activities
20
B
10
A
Link
Link
B depends on A
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30
C
10
A
20
B
40
D
c) A Merge Relationship
C depends on A & B
D depends on C
d) A Burst Relationship
20
B
30
C
40
D
10
A
B depends on A
C depends on B
D depends on B
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e) Start & Finish Dummy Activities
A
C
B
E
D
A
Start
Dummy
Finish
Dummy
C
B
E
D
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83
Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B
D
C,D
E
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Solution :
A E
C
D
B
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85
Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B,C
D
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86. 86
A
C
D
B
Solution :
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87. 87
87
87
87
Example
Draw the arrow network for the project given next.
IPA
Activity
-
A
A
B
A
C
B
D
B,C
E
C
F
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88. 88
Solution :
A PF
C
D
B
E
F
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89. 89
ENGINEERING MANAGEMENT
Lags and Leads
In some situations, an activity cannot start until a
certain time after the end of its Predecessor.
Lag is defined as a minimum waiting period
between the finish (or start) of an activity and the
start (or finish) of its successor.
Arrow networks cannot accommodate lags. The
only solution in such networks is to treat it as a real
activity with a real duration, no resources, and a $0
budget.

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Examples
Place Concrete
3
Strips Forms
2
3
A lag in a node network
Place Concrete Strips Forms
Cure Concrete
A lag in an arrow network

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The term lead simply means a negative lag. It is
seldom used in construction. In simple language: A
positive time gap (lag) means ‘‘after’’ and a negative
time gap (lead) means ‘‘before.’’

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Recommendations for Proper Node Diagram Drawing
Incorrect Correct

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A
B A B
A
B
A
B
Improper proper

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Improper Proper

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Improper Proper

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A
B
C
Improper Proper
A
B
C
PS
(a) Do not start a network with more than one node

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A
B
C
Improper Proper
A
B
C
PF
(a) Do not end a network with more than one node

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The Critical Path Method
(CPM)

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Suppose you decide with your friend to go in
hunting trip.
You must do specific activity such that the trip well
be at the right way. The following activity must be
done.
Introduction

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From chart you can see that the 3rd activity (preparing the
jeep) have the longest period of time any delay with this
activity leads to delay in the trip this activity is a “critical
activity”
Critical activity : An activity on the critical path any delay on
the start or finish of a critical activity will result in a delay in
the entire project
Critical path : The longest path in a network from start to
finish

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Steps Required To Schedule a Project
The preparation of CPM includes the following four steps:
1- Determine the work activities:
The project must be divided into smaller activities
or tasks .
The activity shouldn’t be more than 14-20
days (long durations should be avoided)
Use WBS in scheduling by using an order of
letters and numbers

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2- Determine activity duration:
Duration = Total Quantity / Crew Productivity
The productivity has many sources :
1. The company
2. The market
3. Special books
Note: The scheduler must be aware about the non-working days ,
such as holydays or rain days, etc……

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3- Determine the logical relationships :
This step is a technical matter and obtained
from the project manager and technical team,
and logical relationships shouldn’t confused
with constraints
4- Draw the logic network and perform the CPM
calculations

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5-Reiew and analyze the schedule:
1. review the logic
2. Make sure the activity has the correct predecessor
3. make sure there is no redundant activity

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6- Implement the schedule:
Definition: take the schedule from paper to the execution.
7-Monitor and control the schedule:
Definition: comparing what we planed with what
actually done.
8-Revise the database and record feedback.
9-Resource allocation and leveling.
(will discuss in chapter 6)

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Example
Draw the logic network and perform the CPM calculations for the
schedule shown next.
Duration
IPA
Activity
5
-
A
8
A
B
6
A
C
9
B
D
6
B,C
E
3
C
F
1
D,E,F
G

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In mathematical terms, the ES for activity j is as follows :
ESj =max( EFi )
where (EFi) represents the EF for all preceding activities.
Likewise, the EF time for activity j is as follows :
EF j= ESj + Dur j
where Dur j is the duration of activity j
Forward pass: The process of navigating through a
network from start to end and calculating the completion date
for the project and the early dates for each activity
Forward pass calculations

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A
5
G
1
C
6
D
9
B
8
E
6
F
3
22,23
5,11
5,13 13,22
13,19
11,14
0,5
Solution :

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109
In mathematical terms, the late finish LF for activity j is as follows :
(
LFj =min(LSk
where (LSk) represents the late start date for all succeeding
activities.
Likewise, the LS time for activity j (LS j) is as follows :
LS j= LFj - Dur j
where Dur j is the duration of activity
Backward pass: The process of navigating through a network
from end to start and calculating the late dates for each activity. The
late dates (along with the early dates) determine the critical activities,
the critical path, and the amount of float each activity has.
Backward pass calculations

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110
Solution :
A
5
G
1
C
6
D
9
B
8
E
6
F
3
22,23
5,11
5,13 13,22
13,19
11,14
0,5
22,23
13,22
19,22
16,22
5,13
10,16
0,5
CPM ( ES = LS , EF = LF , TF = FF = 0)

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Four Types Of Floats
There are several types of float. The simplest and most
important type of float is Total Float (TF)
 Total float (TF): The maximum amount of time
an activity can be delayed from its early start
without delaying the entire project.
TF = LS – ES
or
TF = LF - EF
or
TF = LF - Dur - ES

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112
 Free Float: may be defined as the maximum
amount of time an activity can be delayed without
delaying the early start of the succeeding activities
FFi = min(ESi+1) - EFi
where min (ESi+1) means the least (i.e., earliest) of the early start
dates of succeeding activities

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113
In the previous example we can find the free float and total float for
each activity as the following :
Activity C’s free float, FF = 11 - 11 = 0 days
And
Activity C’s total float, TF =16 - 11= 5 days …… and so on.
FF
TF
LF
LS
EF
ES
Duration
Activity
0
0
5
0
5
0
5
A
0
0
13
5
13
5
8
B
0
5
16
10
11
5
6
C
0
0
22
13
22
13
9
D
3
3
22
16
19
13
6
E
8
8
22
19
14
11
3
F
0
0
23
22
23
22
1
G
 Critical activity
 Note : We must always realize that FF ≤ TF

114. ENGINEERING MANAGEMENT
114
 Interfering float: may be defined as the maximum
amount of time an activity can be delayed without
delaying the entire project but causing delay to the
succeeding activities.
TF = FF - Int. or Int. F = TF - FF
 Independent float (Ind. F): we may define it as
the maximum amount of time an activity can be
delayed without delaying the early start of the
succeeding activities and without being affected
by the allowable delay of the preceding activities.
Ind. Fi = min(ESi+1) – max(LFi-1) – Duri
Note: make sure that Ind. F ≤ FF

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Node Format
Activity Name
Activity ID
Duration
ES EF
LS LF
TF FF

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Event Times in Arrow Networks
 The early event time, TE, is the largest (latest) date
obtained to reach an event (going from start to finish).
 The late event time, TL, is the smallest (earliest) date
obtained to reach an event (going from finish to start).
Examples
Perform the CPM calculations, including the event times, for the arrow
network shown below.

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10 30
40
20 60
C
E
B
50
D
F
70
A
G
H
10
5
7
8
9
4
5
8
d1
d2
Arrow network for example

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The preceding logic is similar to that of the forward and backward
passes: When you are going forward, pick the largest number.
When you are going backward, pick the smallest number.
i j
Act. Name
Dur.
TEi
TLi
TEj
TLj
CPM

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119
10 30
40
20 60
C
E
B
50
D
F
70
A
G
H
10
5
7
8
9
4
5
8
d1
d2
10
10
7
0
0
15
10
10
19
19
24
27
27
27
(0,10)
(0,10)
(5,10)
(0,5)
(0,7)
(8,15)
(10,18)
(11,19)
(10,19)
(10,19)
(7,11)
(15,19)
(19,24)
(22,27)
(19,27)
(19,27)

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120
Float Calculations From Event Times
Total Float
TFij = TLj - TEi - Tij
Example ( In the previous network )
TF40-50 = TL50 – TE40 – T40-50
= 19 – 7 – 4 = 8

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Free Float
FFij = TEj - TEi – Tij
Example
FF40-50 = TE50 – TE40 – T40-50
= 19 – 7 – 4 = 8

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Interfering Float
INTFij = TLj – TEj
Example
INTF40-50 = TL50 – TE50
= 19 – 19 = 0
Independent Float
INDFij= TEj – TLi - Tij
Example
INDF40-50 = TE50 – TL40 – T40-50
= 19 – 15 – 4 = 0

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Summary
i j
T
TEi
TLi
TEj
TLj
Float
Direction
TF
FF
Int. F
Ind. F

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Definitions
Activity, or task: A basic unit of work as part of the total project
that is easily measured and controlled. It is time- and resource
consuming.
Backward pass: The process of navigating through a network from
end to start and calculating the late dates for each activity. The late
dates (along with the early dates) determine the critical activities,
the critical path, and the amount of float each activity has.
Critical activity: An activity on the critical path. Any delay in the
start or finish of a critical activity will result in a delay in the entire
project.
Critical path: The longest path in a network, from start to finish,
including lags and constraints.

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Early dates: The early start date and early finish date of an activity.
Early finish (EF): The earliest date on which an activity can finish within project
constraints.
Early start (ES): The earliest date on which an activity can start within project
constraints.
Event: A point in time marking a start or an end of an activity. In contrast to an
activity, an event does not consume time or resources.
Forward pass: The process of navigating through a network from start to end and
calculating the completion date for the project and the early dates for each activity.
Late dates: The late start date and late finish date of an activity.
Late finish (LF): The latest date on which an activity can finish without extending
the project duration.
Late start (LS): The latest date on which an activity can start without extending the
project duration.

126. 126
Precedence Diagram

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The Four Types Relationships
Activities represented by nodes and links that
allow the use of four relationships:
1) Finish to Start – FS
2) Start to Finish – SF
3) Finish to Finish – FF
4) Start to Start – SS

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Finish to Start (FS) Relationship
. The traditional relationship between activities.
. Implies that the preceding activity must finish
before the succeeding activities can start.
. Example: the plaster must be finished before the
tile can start.
Plaster Tile

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Star to Finish (SF) Relationship
. Appear illogical or irrational.
. Typically used with delay time OR LAG.
. The following examples proofs that its logical.
steel
reinforcement
Erect
formwork
Order
concrete
SF
Pour
concrete
5

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Finish to Finish (FF) Relationship
• Both activities must finish at the same time.
• Can be used where activities can overlap to a
certain limit.
Erect
scaffolding
Remove
Old paint
sanding
painting inspect
Dismantle
scaffolding
FF/1
FF/2

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Start to Start (SS) Relationship
• This method is uncommon and non exists in
project construction .
Spread grout
Clean surface
Set tile
SS
Clean floor area

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Advantages of using Precedence Diagram
1. No dummy activities are required.
2. A single number can be assigned to identify each
activity.
3. Analytical solution is simpler.

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Calculation
1) forward calculations
EF = ES + D
Calculate the Lag
LAGAB = ESB – EFA
Calculate the Free Float
FF = Min. (LAG)

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2) Backward calculations
For the last task
LF=EF , if no information deny that.
LS=LF-D
Calculate Total Float
TF = LS – ES OR LF – EF
TFi = Min (lag ij + TFj )
Determine the Critical Path

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135
Example
135
Dur.
ES
EF FF TF LF
LS
A
1 1
2
0
0
2
1
B
9 2
11
0
0
11
2
D
5 11
16
0
0
16
11 4 16
20
0
0
20
16 1 20
21
0
0
21
20
F H
C
5 5
10
3
0
7
2
E
4 10
14
3
0
11
7 6 14
20
3
3
17
11
G
5
4 3
1) Forward pass calculations 4) Backward pass calculations
2) Calculate the Lag ( LAGAB = ESB – EFA)
0
0 0 0 0
0 0
3) Calculate the Free Float (FF) FF = min.( LAG)
5) Calculate total Float (TF = LS – ES OR LF – EF)

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136
Dur.
ES
EF FF TF LF
LS
A
1 1
2
0
0
2
1
B
9 2
11
0
0
11
2
D
5 11
16
0
0
16
11 4 16
20
0
0
20
16 1 20
21
0
0
21
20
F H
C
5 5
10
3
0
7
2
E
4 10
14
3
0
11
7 6 14
20
3
3
17
11
G
5
4 3
6) Determine the Critical Path
0
0 0 0 0
0 0
The critical path passes through the critical activities where TF = 0

137. 137
Resource Allocation and
Resource Leveling

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138
CATEGORIES OF RESOURCES
 Labor
 Materials
 Equipment's.

139. Schedule Updating and Project Control
139

140. 140
Schedule Updating and Project Control
The most important use of schedules is project control :
the scheduler compares actual performance with baseline
performance.
What is Project Control
Project control comprises the following continuous process
1. monitoring work progress .
2.comparing it with the baseline schedule and budget.
3.finding any deviations .
4.taking corrective actions.
ENGINEERING MANAGEMENT

141. 141
Schedule updating
Schedule updating is just one part of the project
control process.
Schedule updating must reflect
 Actual work , and
 involves change orders (CO) .
ENGINEERING MANAGEMENT

142. 142
ENGINEERING MANAGEMENT
Evaluation Questions: main questions and sub-questions

143. ENGINEERING
MANAGEMENT
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MANAGEMENT
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145. 145

146. 146

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MANAGEMENT
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