Engineering Project Management Civil Engineering Department 2 ENGINEERING

Engineering Project Management Civil Engineering Department

2 ENGINEERING MANAGEMENT An-Najah National University Civil Engineering Department Faculty of Engineering Construction Engineering and Management Nabil Dmaidi

3 ENGINEERING MANAGEMENT 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 ENGINEERING MANAGEMENT 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

5 ENGINEERING MANAGEMENT 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

6 What is the Project ENGINEERING MANAGEMENT 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)

7 OR ENGINEERING MANAGEMENT ‘‘a temporary endeavor undertaken to create a unique product, service, or result’’

8 Project Life Cycle ENGINEERING MANAGEMENT

9 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 ENGINEERING MANAGEMENT Project execution 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 monitoring and control ● Tracking progress ● Comparing actual outcome to predicted outcome ● Analyzing variances and impacts ● Making adjustments ● Negotiating for the project team members ● Directing and managing the work ● Working with the team members to help them improve 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

10 ENGINEERING MANAGEMENT

11 ENGINEERING MANAGEMENT Successful project management can then be defined as having achieved the project objectives: objectives ● Within Time ● Within Cost ● At the desired performance/Technology level ● While utilizing the assigned resources effectively and efficiently ● Accepted by the customer

12 What is Project Management ENGINEERING 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.

13 ENGINEERING MANAGEMENT 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

14 ENGINEERING MANAGEMENT The above definition requires further comment. Classical management is usually considered to have five functions or principles: ● Planning ● Organizing ● Staffing ● Controlling ● Directing

15 ENGINEERING MANAGEMENT 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.

16 ENGINEERING MANAGEMENT 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

17 Management Skills ENGINEERING MANAGEMENT � 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

18 Constraints of the project ENGINEERING MANAGEMENT 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.

19 Resources ENGINEERING MANAGEMENT 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

20 ENGINEERING MANAGEMENT q. Actually, the project manager does not control any of these resources directly, except perhaps money (i. e. , the project budget). q. Resources are controlled by the line managers. q. The project manager is responsible for coordinating and integrating activities across multiple, functional lines. The integration activities performed by the project manager include:

21 ENGINEERING MANAGEMENT ● 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

22 ENGINEERING MANAGEMENT Project Scheduling Planning, Scheduling, and Control

23 Planning and Scheduling ENGINEERING MANAGEMENT Planning and scheduling are two terms that are often thought of as synonymous q They are not! q Scheduling is just one part of the planning effort.

24 ENGINEERING MANAGEMENT q Project planning serves as a foundation for several related functions such as cost estimating, scheduling, and project control. q Project scheduling is the determination of the timing and sequence of operations in the project and their assembly to give the overall completion time

25 ENGINEERING MANAGEMENT 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.

26 ENGINEERING MANAGEMENT How much What when The Plan By whom where How Why Figure 1. Planning and Scheduling

27 The Plan ENGINEERING MANAGEMENT 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.

28 ENGINEERING MANAGEMENT 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’.

29 ENGINEERING MANAGEMENT 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.

30 The Tripod of Good Scheduling System ENGINEERING MANAGEMENT 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. Ø If anyone of the above three ‘‘legs’’ is missing, the system will fail.

31 Scheduling and project management ENGINEERING MANAGEMENT Planning, scheduling, and project control are extremely important components of project management includes other components : • cost estimating and management, • procurement, • project/contract administration, • quality management, • and safety management. Ø These components are all interrelated in different ways.

32 ENGINEERING MANAGEMENT Bar (Gantt) Charts

33 DEFINITION AND INTRODUCTION ENGINEERING MANAGEMENT • A bar chart is ‘‘a graphic representation of project activities, shown in a time-scaled bar line with no links shown between activities’’ Ø The bar may not indicate continuous work from the start of the activity until its end. or Ø Non continuous (dashed) bars are sometimes used to distinguish between real work (solid line) and inactive periods (gaps between solid lines)

34 ENGINEERING MANAGEMENT • 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 M 10 Activity Mobilization Bars ( Month or Year )

35 ADVANTAGES OF BAR CHARTS ENGINEERING MANAGEMENT 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. )

36 ENGINEERING MANAGEMENT Bar Charts Loaded with More Info. Such as : budget, man hours and resources. 500$ 220$ 400$ 850$ 140$ 500$ 900$ 10 12 7 11 10 9 15

37 DISADVANTAGES OF BAR CHARTS ENGINEERING MANAGEMENT 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

38 Basic Networks ENGINEERING MANAGEMENT

39 ENGINEERING MANAGEMENT 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.

40 Two classic formats AOA: Activity on Arrow AON: Activity on Node ENGINEERING MANAGEMENT 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

41 ENGINEERING MANAGEMENT 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.

42 ENGINEERING MANAGEMENT Basic Logic Patterns for Arrow Diagrams Node (Event) i i Node (Event) j Activity Name j>i j Each activity should have a unique i – j value (a) Basic Activity

43 ENGINEERING MANAGEMENT 2 A 4 B 10 (b) Independent Activities 3 A 6 B 9 (c) Dependent Activities 12

44 4 2 ENGINEERING MANAGEMENT A C 6 B 8 Activity C depends upon the completion of both Activities A & B (d) A Merge 2 A B 4 C 6 8 Activities B and C both depend upon the completion of Activity A (e) A Burst

45 ENGINEERING MANAGEMENT 12 14 A B C 16 18 D 20 Activities C and D both depend upon the completion of Activities A and B (f) A Cross

46 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B E C, D

47 ENGINEERING MANAGEMENT Solution : B 30 10 A 20 D E 40 C 50

48 Dummy activity (fictitious) ENGINEERING MANAGEMENT * Used to maintain unique numbering of activities. * Used to complete logic, duration of “ 0” * The use of dummy to maintain unique numbering of activities.

49 ENGINEERING MANAGEMENT A Divide node to correct 4 10 B (a) Incorrect Representation 4 A 10 B Dummy 11 (b) Correct Representation

50 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B, C

51 Solution : ENGINEERING MANAGEMENT B 10 A 20 D 30 40 C Improper solution B 30 Dummy 40 D 50 10 A 20 C proper solution

52 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B E B, C F C

53 ENGINEERING MANAGEMENT Solution : B 30 D Dummy 1 10 A 20 50 E Dummy 2 C 40 F 60

54 ENGINEERING MANAGEMENT Removal of Redundant Dummies Original Diagram after removal of redundant dummies (a) A B (b) A B C C

55 ENGINEERING MANAGEMENT Original Diagram (c) (d) Diagram after removal of redundant dummies A C A C B E B E

56 ENGINEERING MANAGEMENT Activity Depends Upon Immediately Preceding Activity (IPA) A B C ----A A, B ----A B Redundant Relationship C

57 Activity List with Dependencies: ENGINEERING MANAGEMENT Activity A B C D E F G H J K L M Description 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 Depends Upon ----A A, B, C, J, M B, C, D, E, K D, E, F, G, L ---------

58 ENGINEERING MANAGEMENT Removing Redundant Relationships: Activity A B C D E F G H J K L M Description 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 Depends Upon ----A A, B, C, J, M B, C, D, E, K D, E, F, G, L ---------

59 ENGINEERING MANAGEMENT L J M A 20 10 F 15 B 5 25 C G E D 35 30 K AOA Representation 40 H 45

60 ENGINEERING MANAGEMENT NODE NETWORKS MTHOD (AON) Link Activity number 10 A Activity name 20 B a) Independent Activities 10 A Link 20 B b) Dependent Activities B depends on A

61 ENGINEERING MANAGEMENT 10 A 30 C 40 D C depends on A & B D depends on C 20 B c) A Merge Relationship 10 A 20 B 30 C 40 D d) A Burst Relationship B depends on A C depends on B D depends on B

62 ENGINEERING MANAGEMENT A D A Start Dummy B C E D Finish Dummy B C e) Start & Finish Dummy Activities E

63 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B E C, D

64 ENGINEERING MANAGEMENT Solution : B D A E C

65 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B, C

66 ENGINEERING MANAGEMENT Solution : B A D C

67 Example ENGINEERING MANAGEMENT Draw the arrow network for the project given next. Activity IPA A - B A C A D B E B, C F C

68 ENGINEERING MANAGEMENT Solution : B A D E C F PF

69 Lags and Leads ENGINEERING MANAGEMENT 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.

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

71 ENGINEERING MANAGEMENT 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. ’’

72 ENGINEERING MANAGEMENT Recommendations for Proper Node Diagram Drawing Incorrect Correct

73 ENGINEERING MANAGEMENT A B A B Improper

74 ENGINEERING MANAGEMENT Improper Proper

75 ENGINEERING MANAGEMENT Improper Proper

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

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

78 The Critical Path Method (CPM)

79 Introduction ENGINEERING MANAGEMENT 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.

80 ENGINEERING MANAGEMENT From chart you can see that the 3 rd 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

81 ENGINEERING MANAGEMENT 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

82 ENGINEERING MANAGEMENT 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……

83 ENGINEERING MANAGEMENT 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

84 ENGINEERING MANAGEMENT 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

85 ENGINEERING MANAGEMENT 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)

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

87 q. Forward pass calculations ENGINEERING MANAGEMENT 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

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

89 q. Backward pass calculations ENGINEERING MANAGEMENT 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.

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

91 Four Types Of Floats ENGINEERING MANAGEMENT There are several types of float. The simplest and most important type of float is Total Float (TF) Ø 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

92 ENGINEERING MANAGEMENT Ø 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

93 ENGINEERING MANAGEMENT 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. Activity Duration ES EF LS LF TF FF A 5 0 5 0 0 B 8 5 13 0 0 C 6 5 11 10 16 5 0 D 9 13 22 0 0 E 6 13 19 16 22 3 3 F 3 11 14 19 22 8 8 G 1 22 23 0 0 § Critical activity § Note : We must always realize that FF ≤ TF

94 ENGINEERING MANAGEMENT Ø 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 Ø 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

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

96 ENGINEERING MANAGEMENT Event Times in Arrow Networks Ø The early event time, TE, is the largest (latest) date obtained to reach an event (going from start to finish). Ø 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.

97 ENGINEERING MANAGEMENT A 10 20 8 D d 1 10 B E 30 9 5 C 7 60 G 5 H 50 8 40 4 F Arrow network for example d 2 70

98 ENGINEERING MANAGEMENT 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. TEi i Act. Name Dur. TEj j TLi CPM

99 ENGINEERING MANAGEMENT 10 A (0, 10) 10 (0, 10) 0 10 0 D 20 8 10 B 5 d 1 (0, 5) (5, 10) C (0, 7) 7 (8, 15) 7 40 4 F 15 24 (10, 18) (11, 19) 10 (10, 19) E 30 9 (10, 19) 10 (7, 11) (15, 19) (19, 24) 60 G 5 (22, 27) (19, 27) H 50 27 19 8 19 (19, 27) d 2 27 70 27

100 ENGINEERING MANAGEMENT Float Calculations From Event Times Total Float TFij = TLj - TEi - Tij Example ( In the previous network ) TF 40 -50 = TL 50 – TE 40 – T 40 -50 = 19 – 7 – 4 = 8

101 ENGINEERING MANAGEMENT Free Float FFij = TEj - TEi – Tij Example FF 40 -50 = TE 50 – TE 40 – T 40 -50 = 19 – 7 – 4 = 8

102 Interfering Float INTFij = TLj – TEj Example INTF 40 -50 = TL 50 – TE 50 = 19 – 19 = 0 Independent Float INDFij= TEj – TLi - Tij Example INDF 40 -50 = TE 50 – TL 40 – T 40 -50 = 19 – 15 – 4 = 0 ENGINEERING MANAGEMENT

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

104 Definitions ENGINEERING MANAGEMENT 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.

105 ENGINEERING MANAGEMENT Early dates: 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: 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.

106 Precedence Diagram

107 ENGINEERING MANAGEMENT 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

108 ENGINEERING MANAGEMENT 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

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

110 ENGINEERING MANAGEMENT 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 FF/1 sanding FF/2 painting inspect Dismantle scaffolding

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

112 ENGINEERING MANAGEMENT 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.

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

114 ENGINEERING MANAGEMENT 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

115 Example ENGINEERING MANAGEMENT 1) Forward pass calculations 4) Backward pass calculations 5) Calculate total Float (TF = LS – ES OR LF – EF) A 1 2 1 0 B 0 1 2 0 2 11 9 0 D 0 2 11 0 11 16 5 0 0 16 7 5 0 E 0 5 7 3 10 11 4 0 H 0 16 20 20 0 0 20 21 4 5 0 2 16 11 4 C F 0 1 20 0 0 21 3 G 0 10 11 3 14 17 6 3 14 3 20 2) Calculate the Lag ( LAGAB = ESB – EFA) 3) Calculate the Free Float (FF) FF = min. ( LAG) ES Dur. LS EF FF TF 115 LF

116 ENGINEERING MANAGEMENT 6) Determine the Critical Path A 1 2 1 0 B 0 1 2 0 2 11 9 0 D 0 2 11 0 11 16 5 0 0 16 7 5 0 E 0 5 7 3 10 11 4 0 H 0 16 20 20 0 0 20 21 4 5 0 2 16 11 4 C F 0 1 20 0 0 21 3 G 0 10 11 3 14 17 6 3 14 3 20 The critical path passes through the critical activities where TF = 0 ES Dur. LS EF FF TF 116 LF

117 Resource Allocation and Resource Leveling

118 ENGINEERING MANAGEMENT CATEGORIES OF RESOURCES q Labor q Materials q Equipment's.

119 Schedule Updating and Project Control

120 Schedule Updating and Project Control ENGINEERING MANAGEMENT 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.

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

122 What is a baseline schedule? ENGINEERING MANAGEMENT