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() Luu Truong Van, Ph D 1 Techniquestools for project planning and scheduling THE OPEN UNIVERSITY OF HO CHI MINH CITY “When all you have is a hammer, every problem is a nail ” Abraham Maslow (1908 1970) Luu Truong Van, Ph D 2 Topics covered • Tools for project scheduling • Bar charts or Gantt charts • Critical Path Method (CPM) • Arrow Diagramming Method (ADM) • Precedence Diagramming Method (PDM) Luu Truong Van, Ph D 3 Schedule Development � Determining start and finish dates for project activ.
THE OPEN UNIVERSITY OF HO CHI MINH CITY Techniques/tools for project planning and scheduling “When all you have is a hammer, every problem is a nail.” Abraham Maslow (1908-1970) Luu Truong Van, Ph.D Topics covered • • • Tools for project scheduling Bar charts or Gantt charts Critical Path Method (CPM): • Arrow Diagramming Method (ADM) • Precedence Diagramming Method (PDM) Luu Truong Van, Ph.D Schedule Development Determining start and finish dates for project activities If start and finish are not realistic, project is unlikely to be finished as scheduled Often iterated many times before determination of project schedule Luu Truong Van, Ph.D Schedule Development Project start & end dates Project calendar List of activities Estimated effort of activities Resource details Dependencies Constraints • Imposed dates • Key events or Milestones Leads & Lags Assumptions Luu Truong Van, Ph.D Schedule Coding System Use coding to sort, group, and filter information: • By WBS level • By responsible party • By area • By discipline • By system/process • By vendor package Luu Truong Van, Ph.D Schedule Coding System Example: Sewer and Water Lines Project Source: Oberlender (2000), p.157 Luu Truong Van, Ph.D Tools for project scheduling Colour graph Bar chart (Gantt chart) Network analysis system • Critical Path Method (CPM) • Program Evaluation and Review Technique (PERT) Luu Truong Van, Ph.D Colour Graph Example: shallow footings Activities 1/9/03 2/9/03 3/9/03 4/9/03 5/9/03 6/9/03 Excavate Pour lean concrete Place rebar Place formwork Pour concrete Luu Truong Van, Ph.D Bar Charts Each activity is depicted as a horizontal bar The length of bar represents the duration of the activity An appropriate time scale on the horizontal axis (days, weeks, months, or calendar dates) Activity inter-relationships are not explicitly shown If applicable, however: • Vertical arrows show logic sequence ties • Float can also be shown by a narrower horizontal bar, a dotted line, or a different colour Luu Truong Van, Ph.D Milestones Tender award Start U/G complete 1-Nov-04 1-Oct-04 1-Sep-04 1-Aug-04 1-Jul-04 1-Jun-04 1-May-04 1-Apr-04 1-Mar-04 1-Feb-04 1-Jan-04 1-Dec-03 1-Nov-03 1-Oct-03 1-Sep-03 1-Aug-03 Date Bar Charts (Cont’d) Finish construction Superstructure complete Finish Elements Sitework Substructure Superstructure Enclosure Interior Electrical Mechanical Commissioning Luu Truong Van, Ph.D 10 “If you trust how the schedule is built Trust what it is telling you!” (Source: unknown) Thank You Luu Truong Van, Ph.D 42 Early Start and Early Finish Perform FORWARD PASS to calculate Early Start and Early Finish dates Luu Truong Van, Ph.D 43 Early Start and Early Finish 7 Task A D= 13 13 Task B D= 16 Task C D=3 16 20 Task D D= Start 3 Task E D= Task F D= 3 Finish Task H D= Task G D= Luu Truong Van, Ph.D 44 Late Start and Late Finish Perform BACKWARD PASS to calculate the Late Start and Late Finish Luu Truong Van, Ph.D 45 Late Start and Late Finish 7 Task A D= 13 13 Task B D= 7 16 Task C D= 13 13 16 16 20 Task D D= Start 16 3 Task E D= 6 Task F D= 11 11 Finish 20 Task H D= 14 14 16 Task G D= 12 14 Luu Truong Van, Ph.D 46 Float 0 7 Task A D= 0 13 13 Task B D= 7 16 Task C D= 13 13 16 16 20 Task D D= Start 16 8 6 Task F D= 11 20 Task E D= Finish 11 Task H D= 14 14 16 Task G D= 12 14 Luu Truong Van, Ph.D 47 Critical Path 0 7 Task A D= 13 13 Task B D= 7 16 Task C D= 13 13 16 16 20 Task D D= Start 16 8 6 Task F D= 11 20 Task E D= Finish 11 Task H D= 14 14 16 Task G D= 12 14 Luu Truong Van, Ph.D 48 Comparison of Planning Models Luu Truong Van, Ph.D 49 Comparison of Planning Models (Cont’d) Luu Truong Van, Ph.D 50 Comparison of Planning Models (Cont’d) Luu Truong Van, Ph.D 51 Comparison of Planning Models (Cont’d) BAR CHART A 10 B A B PRECEDENCE DIAGRAM ACTIVITY ON THE ARROW NETWORK 10 A 10 B Activity B can start at the same time as activity A but not before A d A1 d B A2 5-d A B d B Activity B cannot start until d units of time after activity A has started Luu Truong Van, Ph.D 52 Comparison of Planning Models (Cont’d) Luu Truong Van, Ph.D 53 Comparison of Planning Models (Cont’d) Luu Truong Van, Ph.D 54 Comparison of Planning Models (Cont’d) Luu Truong Van, Ph.D 55 Comparison of Planning Models (Cont’d) Advantages Disadvantages Bar Charts Simple Time scaled Easy to understand Relationships between trades/activities not shown Difficult to update accurately Oversimplify reality Linked Bar Charts Easy to understand Time scaled Includes some activity dependencies Oversimplistic Difficult to update May ignore resources Networks Work sequences shown East to update & alter Must consider resources Complicated Hard to put to time scale Luu Truong Van, Ph.D 56 ... Determining start and finish dates for project activities If start and finish are not realistic, project is unlikely to be finished as scheduled Often iterated many times before determination of project. .. the project completion will be delayed There can be more than one critical path for a project Luu Truong Van, Ph.D 25 Critical Path Analysis Forward pass: ES and EF Procedure: • Fill in the ES and. .. A B 10 C 20 E Project Start D Project Finish F G I H Luu Truong Van, Ph.D 36 PDM: An Example Network analysis: forward pass 10 10 A 10 12 B 25 10 35 C 20 25 E 0 0 Project Start D Project Finish