Construction Project Scheduling and Control E-Book

Saleh A. Mubarak

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 950

Veröffentlichungsjahr: 2019

Beschreibung

Ensure successful construction projects through effective project scheduling and control

The success of a construction project is dependent on a schedule that is well-defined yet flexible to allow for inevitable delays or changes. Without an effective schedule, projects often run over budget and deadlines are missed which can jeopardize the success of the project. The updated Construction Project Scheduling and Control, Fourth Edition is a comprehensive guide that examines the analytical methods used to devise an efficient and successful schedule for construction projects of all sizes. This Fourth Edition describes the tools and methods that make projects run smoothly, with invaluable information from a noted career construction professional.

Construction Project Scheduling and Control, Fourth Edition offers construction professionals a redefined Critical Path Method (CPM) and updated information on Building Information Modeling (BIM) and how it impacts project control. This Fourth Edition includes worked problems and scheduling software exercises that help students and practicing professionals apply critical thinking to issues in construction scheduling. This updated edition of Construction Project Scheduling and Control:

• Includes a revised chapter on the Critical Path Method (CPM) and an all-new chapter on project scheduling and control as viewed through the owner's perspective
• Provides numerous worked problems and construction scheduling exercises
• Includes an expanded glossary and list of acronyms
• Offers updated instructor materials including PowerPoint lecture slides and an instructor's manual

Written for undergraduate and graduate students in construction management, civil engineering, and architecture, as well as practicing construction management professionals, Construction Project Scheduling and Control, Fourth Edition is updated to reflect the latest practices in the field.

Leseprobe

Table of Contents

Cover

Preface

Preface to the First Edition

Chapter 1: Introduction

PLANNING AND SCHEDULING

PROJECT CONTROL

WHY SCHEDULE PROJECTS?

THE SCHEDULER

SCHEDULING AND PROJECT MANAGEMENT

CHAPTER 1 EXERCISES

NOTES

Chapter 2: Bar (Gantt) Charts

DEFINITION AND INTRODUCTION

ADVANTAGES OF BAR CHARTS

DISADVANTAGES OF BAR CHARTS

CHAPTER 2 EXERCISES

Chapter 3: Basic Networks

DEFINITION AND INTRODUCTION

ARROW NETWORKS

NODE NETWORKS

COMPARISON OF ARROW AND NODE NETWORKS

NETWORKS VERSUS BAR CHARTS

TIME‐SCALED LOGIC DIAGRAMS

CHAPTER 3 EXERCISES

Chapter 4: The Critical Path Method (CPM)

INTRODUCTION

STEPS REQUIRED TO SCHEDULE A PROJECT

BEGINNING‐OF‐DAY OR END‐OF‐DAY CONVENTION

THE CPM EXPLAINED THROUGH EXAMPLES

LOGIC AND CONSTRAINTS

CHAPTER 4 EXERCISES

Chapter 5: Precedence Networks

DEFINITION AND INTRODUCTION

THE FOUR TYPES OF RELATIONSHIPS

CPM CALCULATIONS FOR PRECEDENCE DIAGRAMS

INTERRUPTIBLE ACTIVITIES

MULTISTAGE ACTIVITIES

TYPES OF LAGS

FINAL DISCUSSION

CHAPTER 5 EXERCISES

Chapter 6: Resource Allocation and Resource Leveling

INTRODUCTION

THE THREE CATEGORIES OF RESOURCES

WHAT IS RESOURCE ALLOCATION?

RESOURCE LEVELING

MATERIALS MANAGEMENT

CHAPTER 6 EXERCISES

Chapter 7: Schedule Updating and Project Control

INTRODUCTION

THE NEED FOR SCHEDULE UPDATING

PROJECT CONTROL DEFINED

SCHEDULE UPDATING

PROJECT CONTROL

CHAPTER 7 EXERCISES

Chapter 8: Schedule Compression and Time‐Cost Trade‐Off

INTRODUCTION

HOW IMPORTANT IS IT TO FINISH ON SCHEDULE?

SETTING PRIORITIES

ACCELERATING A PROJECT

CONSTRUCTION AND MODULARIZATION

DIRECT AND INDIRECT COSTS

RECOVERY SCHEDULES

ACCELERATING PROJECTS USING COMPUTERS

POTENTIAL ISSUES WITH UNCOORDINATED PROJECT ACCELERATION

CHAPTER 8 EXERCISES

Chapter 9: Reports and Presentations

INTRODUCTION

THE DIFFERENCE BETWEEN REPORTS AND PRESENTATIONS

SKILLS NECESSARY FOR GIVING GOOD PRESENTATIONS

THE POWER OF PRESENTATIONS

REVIEWING REPORTS BEFORE AND AFTER PRINTING

GENERAL TIPS ON PRINTING REPORTS

SUMMARY REPORTS

PAPER OR ELECTRONIC REPORTS?

COMMUNICATIONS IN THE INTERNATIONAL ENVIRONMENT

CHAPTER 9 EXERCISES

Chapter 10: Scheduling as Part of the Project Management Effort

INTRODUCTION

PROJECT OBJECTIVES

DEFINING AND MEASURING PROJECT SUCCESS

SCHEDULING AND ESTIMATING

ESTIMATING AND ACCOUNTING

SCHEDULING AND ACCOUNTING

SCHEDULING AND CHANGE ORDERS

PAPERLESS PROJECT MANAGEMENT

PROCUREMENT MANAGEMENT

MANAGEMENT OF SUBMITTALS

THE MASTER SCHEDULE AND SUBSCHEDULES

MULTIPROJECT MANAGEMENT

TIME CONTINGENCY AND MANAGEMENT OPTIONS

CHAPTER 10 EXERCISES

Chapter 11: Other Scheduling Methods

INTRODUCTION

PROGRAM EVALUATION AND REVIEW TECHNIQUE (PERT)

GRAPHICAL EVALUATION AND REVIEW TECHNIQUE (GERT)

LINEAR SCHEDULING METHOD (LSM)

LSM AND PROJECT SCHEDULE ACCELERATION

CHAPTER 11 EXERCISES

Chapter 12: Dynamic Minimum Lag Relationship

INTRODUCTION

SIMILARITY BETWEEN THE DML CONCEPT AND THE LINEAR SCHEDULING METHOD (LSM)

HOW DOES DML WORK?

DML RELATIONSHIP IN CPM CALCULATIONS

CONCLUSION

CHAPTER 12 EXERCISES

Chapter 13: The Critical Path Definition: Revisited

INTRODUCTION

WHAT

IS

THE “LONGEST PATH”?

THE CRITICAL PATH THROUGH EXAMPLES

RESOURCE ALLOCATION AND RESOURCE LEVELING

THE AACE RECOMMENDED PRACTICES NO. 49R‐06 AND 92R‐17

PROPOSED DEFINITION OF THE CRITICAL PATH

CHANGES IN THE CRITICAL PATH

Chapter 14: Construction Delays and Other Claims

INTRODUCTION

DELAY CLAIMS

REASONS FOR CLAIMS

FORCE MAJEURE

TYPES OF DELAYS

SCHEDULING MISTAKES RELATED TO DELAY CLAIMS

PROJECT DOCUMENTATION

DELAY CLAIMS RESOLUTION

THE IMPORTANCE OF CPM SCHEDULES IN DELAY CLAIMS

METHODS OF SCHEDULE ANALYSIS

CHAPTER 14 EXERCISES

Chapter 15: Schedule Risk Management

INTRODUCTION

TYPES OF RISK IN CONSTRUCTION PROJECTS

SCHEDULE RISK TYPES

DEFINITION OF RISK TERMS

IMPORTANCE OF GOOD PLANNING FOR RISK MANAGEMENT

IMPORTANCE OF GOOD CPM SCHEDULING PRACTICES FOR RISK ASSESSMENT

RISK SHIFTING IN CONTRACTS

SCHEDULE RISK MANAGEMENT STEPS

EXPECTED VALUE

APPLICATION IN SCHEDULING

EXAMPLES OF RISK ADJUSTMENT

CONCLUSION

CHAPTER 15 EXERCISES

Chapter 16: BIM‐Based 4D Modeling and Scheduling

OVERVIEW OF BUILDING INFORMATION MODELING (BIM)

CASE STUDY

CHAPTER 16 EXERCISES

Chapter 17: Project Scheduling for Owners

INTRODUCTION

PROJECT INITIATION PROCESS

PROJECT FINANCING

REQUIRING AND APPROVING A SCHEDULE

CHAPTER 17 EXERCISES

Appendix A: Computer Project

GENERAL GUIDELINES

COST LOADING

UPDATING THE PROJECT

CHANGE ORDER

RESOURCE LEVELING

SCHEDULE COMPRESSION 1

SCHEDULE COMPRESSION 2

DELAY CLAIM 1: UNFORESEEN CONDITIONS

DELAY CLAIM 2: CHANGE IN THE OWNER'S REQUIREMENTS

Appendix B: Sample Reports

TABULAR REPORTS

GRAPHIC REPORTS

Abbreviations

Glossary

Bibliography

PLANNING, SCHEDULING, AND PROJECT CONTROL

PROJECT MANAGEMENT/CONSTRUCTION MANAGEMENT

CONSTRUCTION SCHEDULING LAW

OTHER

Index

End User License Agreement

List of Tables

Chapter 10

Table 10.1 Project Success Measuring Model

Table 10.2a Cost grading table

Table 10.2b Schedule grading table

Table 10.3 Project Success Grading Tiers

Chapter 11

Table 11.1 Z Table: Cumulative Probability of the Standard Normal Distributio...

Chapter 16

Table 16.1 Some BIM Tools to Develop 4D Models

Appendix B

Table B.1 Tampa Office Building—Update as of 31‐Aug‐2010

Table B.2 Apex Project—List of Activities (an asterisk indicates a constraint...

Table B.3 List of Activities with Predecessors and Successors

Table B.4 Earned Value Report

Table B.5 Apex Project—Resource Control—Summary by Resource

List of Illustrations

Chapter 1

Figure 1.1 Programs, portfolios, and projects.

Figure 1.2 Planning and scheduling.

Figure 1.3 The Tripod of the Scheduling System

Chapter 2

Figure 2.1 Bar chart for placing a simple slab on a grade.

Figure 2.2 Alternative bar chart for placing a simple slab on a grade placed...

Figure 2.3 Bar chart for placing a simple slab on a grade, with activities “...

Figure 2.4 Bar chart—loaded with man‐hours—for construction of a two‐story b...

Figure 2.5 Bar chart—loaded with the budget—for construction of a two‐story ...

Figure 2.6 Bar chart for replacement of an old roof, showing a comparison be...

Figure 2.7 Bar chart representing the summary activities for constructing a ...

Chapter 3

Figure 3.1 Solution for Example 3.1: a simple arrow network.

Figure 3.2a Improper solution for Example 3.2.

Figure 3.2b Proper solution for Example 3.2.

Figure 3.2c Other proper solutions for Example 3.2.

Figure 3.3 (a) Improper solution, (b) another improper solution, and (c) pro...

Figure 3.4 Solution for Example 3.4.

Figure 3.5 Solution for Example 3.5.

Figure 3.6 Solution for Example 3.6.

Figure 3.7 Solution for Example 3.7.

Figure 3.8 Redundant versus needed dummy activities.

Figure 3.9 Solution for Example 3.1 as a node network.

Figure 3.10 Solution for Example 3.2 as a node network.

Figure 3.11 Solution for Example 3.3 as a node network.

Figure 3.12 Solution for Example 3.4 as a node network.

Figure 3.13 Solution for Example 3.5 as a node network.

Figure 3.14 Solution for Example 3.6 as a node network.

Figure 3.15 Solution for Example 3.7 as a node network.

Figure 3.16 (a) A lag in a node network; (b) a lag in an arrow network.

Figure 3.17 Nodes and milestones in node networks.

Figure 3.18 Node connection in node networks.

Figure 3.19 Node order in node networks.

Figure 3.20 Relationship lines in node networks.

Figure 3.21 Intersecting relationship lines in node networks.

Figure 3.22 Converging the start and finish of node networks.

Figure 3.23 Time‐scaled logic diagram or bar chart with logic links.

Chapter 4

Figure 4.1 Bar chart for introductory hunting trip example,

Figure 4.2 Sample work breakdown structure (WBS). This breakdown shows compl...

Figure 4.3 Level of confidence forces the breakdown of one activity while an...

Figure 4.4 Level of confidence relationship with activities' breakdown le...

Figure 4.5 Common scheduling errors: (a) redundant relationship; (b) logic l...

Figure 4.6 Completed logic network: (a) forward pass; (b) forward and backwa...

Figure 4.7 Node diagram for Example 4.2.

Figure 4.8 Free float with (a) one successor activity and (b) more than one ...

Figure 4.9 Node diagram for Example 4.3.

Figure 4.10 Node formats: (a) activity ID and name, duration, early start (E...

Figure 4.11 Lags in a CPM network.

Figure 4.12 Lags in scheduling software.

Figure 4.13 Two‐day lag.

Figure 4.14 Effect of choice of dates on cash flow.

Figure 4.15 (a) Arrow network for Example 4.7; (b) event times in arrow netw...

Figure 4.16 Effect of imposed finish date on the schedule.

Chapter 5

Figure 5.1 Bar chart for five consecutive activities.

Figure 5.2 Bar chart for five overlapping activities.

Figure 5.3 Stair‐type schedule for utility pipe installation project....

Figure 5.4 Precedence diagram, for utility pipe installation project, using ...

Figure 5.5 Precedence diagram, for utility pipe installation project, using ...

Figure 5.6 Precedence diagram, for utility pipe installation project, using ...

Figure 5.7 Precedence diagram, for utility pipe installation project, using ...

Figure 5.8 Percent complete approach: (a) activity B starts after activity A...

Figure 5.9 (a) Traditional way: Design‐Bid‐Build, (b) stair‐type diagram, an...

Figure 5.10 (a) Typical predecessor relationship; (b) parallel predecessor r...

Figure 5.11 Three‐activity project using a start‐to‐start relationship....

Figure 5.12 Three‐activity project using a start‐to‐start relationship with ...

Figure 5.13 Three‐activity project, with 10‐day duration, using a finish‐to‐...

Figure 5.14 Three‐activity project, with 12‐day duration, using a finish‐to‐...

Figure 5.15 Three‐activity project, with a 10‐day duration, using a combinat...

Figure 5.16 Three‐activity project, with 9‐day duration, using a combination...

Figure 5.17 Three‐activity project, with 7‐day duration, using a combination...

Figure 5.18 Figure 5.17 redrawn.

Figure 5.19 Example of a dangling activity.

Figure 5.20 Another example of a dangling activity.

Figure 5.21 Three alternative approaches: (a) The bar chart. (b) Activity B ...

Figure 5.22 Network for Example 5.1.

Figure 5.23 Solution for Example 5.1.

Figure 5.24 Network for the detailed approach.

Figure 5.25 Network in Figure 5.24 with contiguous activities.

Figure 5.26 Network for Example 5.1 with contiguous activities.

Figure 5.27 Network for Example 5.2.

Figure 5.28 Solution for Example 5.2 with interruptible activities.

Figure 5.29 Solution for Example 5.2 with contiguous activities.

Figure 5.30a Network with interruptible activities.

Figure 5.30b Network with contiguous activities.

Figure 5.30c Remedy 1: Network with elastic (stretchable) activities.

Figure 5.30d Remedy 2: Network with split activities.

Figure 5.30e Remedy 2: Network with Split Activities and only FS relationshi...

Figure 5.30f Bar Chart for the networks in Figure 5.30 (d) and (e).

Figure 5.31 (a) Specialty work shown as one continuous activity. (b) Special...

Figure 5.32 (a) Wait lag: Concrete placement and stripping forms. (b) Wait l...

Figure 5.33 (a) Start lag using Start‐to‐Start (SS) relationship. (b) Splitt...

Figure 5.34 Continuous lag between predecessors and successors.

Chapter 6

Figure 6.1 Precedence diagram for Example 6.2 (PS, project start).

Figure 6.2 (a) Bar chart for Example 6.2 with an unleveled labor assignment ...

Figure 6.3 (a) Bar chart for Example 6.2 with a leveled labor assignment (wi...

Figure 6.4 (a) Bar chart for Example 6.2 with the labor assignment leveled a...

Figure 6.5 Logic network solution for Example 6.3.

Figure 6.6 Bar chart for Example 6.3 with an unleveled labor assignment.

Figure 6.7a Bar chart for Example 6.3 with the labor assignment leveled and ...

Figure 6.7b Bar chart for Example 6.3 with the labor assignment leveled and ...

Figure 6.8 Bar chart for Example 6.3 with the labor assignment leveled and a...

Figure 6.9 Bar chart for Example 6.3 with the labor assignment leveled and a...

Figure 6.10 Bar chart for Example 6.3 with the labor assignment leveled, a m...

Figure 6.11 Bar charts for Example 6.3 with the labor resource driving the d...

Figure 6.12 Bar chart for Example 6.3 with labor resource driving the durati...

Figure 6.13 The effect of changing (a) an FS (finish‐to‐start) relationship ...

Figure 6.14

Chapter 7

Figure 7.1 Data date and update zones: past, current, and future.

Figure 7.2 (a) Four overlapping activities, planned to take 14 days overall;...

Figure 7.3 (a) Activities A and B of a project; (b) retained logic after 6 d...

Figure 7.4 (a) Schedule created after piles have been driven (actual duratio...

Figure 7.5 Effect of removing an activity from a schedule: removal of AS250 ...

Figure 7.6 Dissolving activity B.

Figure 7.7 Adding an activity to the schedule: (a) original logic; (b) resul...

Figure 7.8 (a) Original schedule; (b) updating the schedule; (c) updated sch...

Figure 7.9 Updating a report without costs listed (most common type of repor...

Figure 7.10 Updating a report for a cost‐loaded schedule (less common type o...

Figure 7.13 Project update cycle.

Figure 7.14 Design development: (a) 90% activity as originally planned; (b) ...

Figure 7.15 Schedule Updated for Example 7.1 with Slippage not Allowed.

Figure 7.16 Percent complete based on duration.

Figure 7.17 Workday unit percent complete.

Figure 7.18 Workday unit percent complete: actual versus baseline.

Figure 7.19 Example 7.2: Installing three doors.

Figure 7.20 Schedule performance versus budget performance_ quadrant I, ahea...

Figure 7.21 Earned value (budgeted cost for work performed, or BCWP) and act...

Chapter 8

Figure 8.1 Combination relationship: (a) Normal duration, finish‐to‐start (FS)...

Figure 8.2 Fast‐tracking.

Figure 8.3 Cumulative effect of overtime on productivity (50‐ and 60‐hour wo...

Figure 8.4 Cumulative cost of overtime successive weeks' productivity lo...

Figure 8.5 Acceleration and fast‐tracking.

Figure 8.6 Project with eight paths.

Figure 8.7 Nonlinear increase in direct costs with project acceleration.

Figure 8.8 Linear decrease in indirect costs with project acceleration.

Figure 8.9 Effect of project acceleration on total cost: the general case, i...

Figure 8.10 Effect of project acceleration on total cost: a special case, in...

Figure 8.11 Effect of project acceleration on total cost: a special case, in...

Figure 8.12 Precedence network for project in Example 8.1—PF, project finish...

Figure 8.13 Time‐cost trade‐off calculation table for Example 8.1....

Figure 8.14 Market conditions. This curve does not accurately reflect past m...

Chapter 10

Figure 10.1 Project objectives.

Figure 10.2 Project objective and constraints.

Figure 10.3 Evolution of a schedule and cost estimate for a project.

Figure 10.4 Subnet of a master schedule with two activities belonging to one...

Figure 10.5 (a) Real durations; (b) “fluffed” durations; (c) manipulated log...

Chapter 11

Figure 11.1 Probability density function curve (shaded area indicates the pr...

Figure 11.2 Solution to Example 11.1, part 1.

Figure 11.3 Solution to Example 11.1, part 2.

Figure 11.4 Solution to Example 11.1, part 3.

Figure 11.5 Solution to Example 11.1, part 4.

Figure 11.6 Solution to Example 11.1, part 5.

Figure 11.7 Solution to Example 11.1, part 6.

Figure 11.8 Solution to Example 11.1, part 7.

Figure 11.9 Solution to Example 11.1, part 8.

Figure 11.10 CPM network solution to Example 11.2.

Figure 11.11 (a) Deterministic and (b) probabilistic branching.

Figure 11.12 Three possible outcomes following activity A.

Figure 11.13 The linear scheduling method (LSM).

Figure 11.14 Time and distance buffers in the LSM.

Figure 11.15 A successor's getting ahead of its predecessor: an illegal r...

Figure 11.16 Solution 4 for avoiding an intersection in the LSM.

Figure 11.17 Combination of solutions 2 and 4 for avoiding an intersection i...

Figure 11.18 Rate of successor slower than rate of predecessor in the LSM. P...

Figure 11.19 Time buffer calculation in the LSM. Practically, activity A fin...

Figure 11.20 (a) Solution to example 11.4. (b) Solution to example 11.4 usin...

Figure 11.21 Logic diagramming method (LDM notation).

Figure 11.22 NetPoint schedule with resources.

Figure 11.23 CPS transforms complex relationships into FS with no lag.

Figure 11.24 Sample as‐built schedule with recorded progress events.

Chapter 12

Figure 12.1 The dynamic minimum lag (DML) relationship.

Figure 12.2 Two overlapping activities represented in LSM graph and three di...

Figure 12.3 Examples in which the successor (activity B) has gotten ahead of...

Figure 12.4 SS Relationship with a percent lag.

Figure 12.5 Activity A (Roof Sheathing) as the predecessor an activity B (In...

Figure 12.6 Situations in which the DML relationship does not work because t...

Figure 12.7 A situation in which the DML relationship cannot be used in lieu...

Figure 12.8 A better alternative to depict the logic of the network in Figur...

Figure 12.9 A situation in which the DML relationship cannot be used in lieu...

Chapter 13

Figure 13.1 Normal case with no lags, imposed finish date, or constraints

Figure 13.2 A schedule with an imposed finish date later than its calculated...

Figure 13.3 A schedule with an imposed finish date earlier than its calculat...

Figure 13.4 A schedule with lags between some activities

Figure 13.5 A schedule with constraints that impact the critical path and th...

Figure 13.6 A schedule similar to the one shown in Figure 13.5 but activity ...

Figure 13.7a All activities are on the same (5‐workday/week) calendar...

Figure 13.7b Some activities are on a 5‐workday/week calendar while others a...

Figure 13.8a Three activities connected with start‐to‐start relationships wi...

Figure 13.8b A bar chart showing the activities in Figure 13.8a. The compute...

Figure 13.8c A bar chart showing the activities in Figure 13.8a. Activities ...

Figure 13.8d A bar chart showing the activities in Figure 13.8a but with act...

Figure 13.8e The same three activities in Figure 13.8a but connected with fi...

Figure 13.8f The same three activities in Figure 13.8a but connected with fi...

Figure 13.9 An example of a continuous lag, where the lag has to be maintained...

Figure 13.10a Activities B and C are logically independent but activity C ha...

Figure 13.10b With an additional crew, activities B and C, in Figure 13.10a,...

Figure 13.10c Activity A in Figure 13.10b was accelerated from 10 to 8 days,...

Chapter 14

Figure 14.1 CPM network for Example 14.1.

Figure 14.2 Bar chart with sequence dependencies.

Figure 14.3 Bar chart with resource constraints.

Figure 14.4 Bar chart with impact of owner's delay to activity E. The ow...

Figure 14.5 With the impact of owner's delay to activity E but mitigated ...

Figure 14.6 Alternate version of Figure 14.3, redrawn with activities C, F, ...

Figure 14.7 The timing of the delay notification becomes important in permit...

Chapter 16

Figure 16.1 An example of the representation of a building with BIM.

Figure 16.2 Representation of how information about a building column is sto...

Figure 16.3 Representation of how information about a building wall is store...

Figure 16.4 Summary of functions of nD BIM.

Figure 16.5 Work flow for creating a 4D model.

Figure 16.6 General view of the building.

Figure 16.7 Snapshot of how to import a 3D model into Navisworks.

Figure 16.8 Snapshot of general view of the Navisworks TimeLiner.

Figure 16.9 Snapshot of how to define column types.

Figure 16.10 Snapshot of TimeLiner column types.

Figure 16.11 Snapshot of Data Sources tab in Navisworks TimeLiner.

Figure 16.12 Snapshot of types of external data sources available in Naviswo...

Figure 16.13 Snapshot of commands in the Data Sources tab.

Figure 16.14 Snapshot of the Configure tab in Navisworks TimeLiner.

Figure 16.15 Snapshot of adding a new task type.

Figure 16.16 Snapshot of Appearance Definitions.

Figure 16.17 Snapshot of the shortcut for Appearance Definitions.

Figure 16.18 Snapshot of the Selection Tree.

Figure 16.19 Snapshot of the Selection Tree demonstrating details of the con...

Figure 16.20 Snapshot of how to link Selection Sets and TimeLiner Tasks.

Figure 16.21 Snapshot of the Simulate tab in TimeLiner.

Figure 16.22 Snapshot of how to define animation settings.

Figure 16.23 Snapshot of the 4D model of the building, Example 1.

Figure 16.24 Snapshot of the 4D model of the building, Example 2.

Figure 16.25 Snapshot of the 4D model of the building, Example 3.

Figure 16.26 Snapshot of the 4D model of the building, Example 4.

Figure 16.27 Snapshot of the 4D model of the building, Example 5.

Figure 16.28 Snapshot of the 4D model of the building, Example 6.

Figure 16.29 Snapshot of the 4D model of the building, Example 7.

Figure 16.30 Snapshot of the Export Animation command.

Figure 16.31 Snapshot of the Animation Export settings.

Figure 16.32 Integrated solutions for building a life cycle using BIM.

Chapter 17

Figure 17.1 Project Initiation Process.

Figure 17.2 Impact of timing on change.

Figure 17.3 The Evolution of the Schedule.

Figure 17.4 Cash Flow Diagram.

Guide

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Table of Contents

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Construction Project Scheduling and Control

Fourth Edition

Saleh Mubarak

This edition first published 2019©2019 John Wiley & Sons, Inc.

Edition HistoryPearson (2005,1e), John Wiley & Sons (2010, 2e), John Wiley & Sons (2015, 3e)

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Preface

This is the Fourth Edition of Construction Project Scheduling and Control. I am very pleased with its continuous success. The book continues to be one of the most, if not the most, popular references in its field throughout the world, both in paper and digital forms. I keep receiving correspondence—comments, suggestions, requests for instructional materials (instructor support materials including an Instructor's Manual and PowerPoints can be accessed by visiting http://www.wiley.com/buy/9781119499831 and clicking on the “More Information About this Book” link). The most praised traits of the book are its simplicity, comprehensiveness, and practical examples. I was so happy and proud when the language editor (of the first edition) corrected me regarding an activity's total float in an example in the book. She had no technical background but had learned the critical path method while reviewing my book!

During the past fifteen years, I have been using my book in professional seminars and college classes as well as discussing it with my friends, colleagues, and students. I have always kept a log of all suggestions and corrections I discover or receive. I started thinking about the second edition just after the first edition was published in 2004 and about the third edition just after the second edition was published in 2010, and about this edition right after the third edition came out in 2015. I added two new chapters: A chapter on project scheduling and control from the owner's perspective. This chapter, in my opinion, is important since all books that I am aware of, were written from the contractor's perspective. The second chapter is dedicated to the definition of the critical path since I see many holes in existing definitions. I purposely placed this chapter near the end of the book and after we dealt with all topics impacting the critical path definition, so we can be able to discuss all possible related scenarios. At the end of the chapter, I wrote my own definition, which will be subject to discussion and debate. I threw a stone into a still pond; provoking the rethinking and debate on the definition of the most important concept in project scheduling. In addition, I made many additions, changes, and corrections to almost every chapter.

Although I was very happy and content with the way the book came out and was received, I believe there is no such thing as the perfect human product. Imperfection is part of human nature, but we should think of it positively: there is always room for improvement. I had to parallel my satisfaction and ambition in completing this fourth edition with a strong conviction that the fifth edition will be coming out in a few years. In my professional seminars and college courses, even though the course or seminar may be the same, I make updates and adjustments every time I teach it. I believe in continuous improvement and in the saying, “My today must be better than my yesterday, and my tomorrow must be better than my today.”

One experience has added to my knowledge and the book—the overseas jobs that I have held between 2008 and 2014. I could not imagine the pace and amount of construction in such a small place as Qatar. There are more tower cranes than you can count. Professionals come from all over the world, like a huge bouquet of flowers, with their diversity in education, culture, race, and language. Communication is a challenge, to say the least. Even though English is the official language for doing business in most organizations there, one soon realizes that English is not English! Forget about the difference in pronunciation and accents, forget about the spelling of labor versus labour and program versus programme; there are differences in the interpretation of technical terms and in the way business is conducted. To make it interesting, none of these differences is wrong. This situation is the cure for what I call the background paradigm syndrome, in which everyone believes he or she is right just because he or she was brought up this way! Then our cultures and ways of doing business clash, and everyone believes the other persons is wrong! In many of these situations, there is no right or wrong; there are just different ways of doing things. However, in a project management team, all must sing together in harmony with one common tune—what a challenge! Keep in mind, our field is an empirical/experimental, not an exact, science! Believe it or not, I enjoy every minute of this “clash of cultures.” I think of it like this: “one cubic meter of concrete mix: $100; one ton of steel: $600; one workday with 30 different nationalities: priceless!”

Since the first edition, I have observed more qualitative interest in project scheduling in the professional and academic disciplines. In particular, the Project Management Institute (PMI) has created a certification track in scheduling (Scheduling Professional, PMI‐SP) in 2008 (the author served in the committee that prepared the first SP exam), and the AACE International has its own Planning & Scheduling Professional (PSP) certification. Other professional organizations, such as the American Institute of Architecture (AIA), the Construction Management Association of America (CMAA), the Associated General Contractors (AGC), the UK's Chartered Institute of Building (CIOB), and many others inside and outside the United States have also showed increased interest in scheduling and project control issues. This, coupled with the increasing role of project scheduling (using the critical path method) in delay and other claims, has made it an essential part of the required knowledge for judges, lawyers, and arbitrators. This is a clear indication of the importance of project scheduling and control for today's bigger and more complicated projects. Managing time can be the difference between success and failure.

To all my readers—construction and other professionals, educators, and students—I would like to hear from you. If you have a question, suggestion, comment, or correction, please send me an e‐mail at [email protected]. I promise to make every effort to read and respond to every e‐mail that I receive. Such communication will elevate us in the pursuit of perfection.

Preface to the First Edition

This is the third edition of Construction Project Scheduling and Control. I am very pleased with its continuous success. The book has become popular throughout the world, both in paper and in digital form. I continuously receive correspondence—comments, suggestions, requests for instructional materials (instructor support materials including an instructor manual and PowerPoints can be accessed by visiting http://www.wiley.com/buy/9781118846001 and clicking on the “More Information About this Book” link), and compliments. The most praised traits of the book are its simplicity, comprehensiveness, and practical examples. I was so happy and proud when the language editor (of the first edition) corrected me regarding an activity's total float in an example in the book. She had no technical background but had learned the critical path method while linguistically reviewing my book!

During the past nine years, I have been using my book in professional seminars and college classes. I have discussed it with my friends, colleagues, and students. I have always kept a log of all suggestions and corrections. I started thinking about the second edition just after the first edition was published in 2004 and about the third edition just after the second edition was published in 2010. I have modified the definition of the critical path after so many readings and discussions with experts and colleagues. I think I have now the most accurate definition in all of the literature available. Is it possible that I modify the definition in the future? Absolutely!

Although I was very happy and content with the way the book came out and was received, I believe there is no such thing as the perfect human product. Imperfection is part of human nature, but we should think of it positively: there is always room for improvement. I have had to parallel my satisfaction and ambition in completing this third edition with a strong conviction that the fourth edition will be coming out in a few years. In my professional seminars and college courses, even though the course or seminar may be the same, I make updates and adjustments every time I teach it.

Chapter 1Introduction

Interstate 4 and 17/92 intersection in Sanford, Florida

PLANNING AND SCHEDULING

Planning and scheduling are two terms that are often thought of as synonymous. However, they are not. Scheduling is just one part of the planning effort. The term planning is used in many ways and different contexts. We commonly hear about financial planning, such as retirement planning and college education planning. Although these types of planning may include other aspects (such as what to do after retirement or which college to choose for your child), the main focus is on finance. Government organizations, as well as large corporations, have planning units or teams in almost every department. All plans in the individual units must be aligned with the organization's “strategic plan,” which is the long‐term plan for the organization itself in terms of operations and growth. At the individual level, a young person may have plans for marriage, a career, and so forth. However, in the context of this book, the term planning is restricted to mean project planning, with an emphasis on construction projects.

What Is a Project?

Before we define project planning, we need to define a project. The Project Management Institute (PMI) defines a project as “a temporary endeavor undertaken to create a unique product, service, or result” (PMBOK, 6th ed, 2017, p. 715). The key words in this definition are temporary and unique: any project must have a starting point and an ending point, and it must have a deliverable product, service, or result that is unique. As a generic example, a secretary of education saying, “We need to improve our students' SAT scores” does not constitute a project. However, saying, “We need to improve our students' SAT scores by an average of 15 points in five years” may qualify as a project. Another example: a newlywed couple may decide on saving money to buy a house. This is not a project, but saying, “We are planning to save $50,000 in the next five years” may qualify as a project.

Tip Box 1.1

Every project must have a start point, a finish point, and a deliverable.

Some government agencies have specific but ongoing work that they call a project, such as maintenance of a certain facility or park, compliance with the Americans with Disabilities Act, or other regulation. Technically, these are not projects because they have no well‐defined deliverable product or service and/or starting and ending points. Each could be called a program, instead, with several projects within each program. Basically, we need to distinguish between a program and a project:

Program

: A

program

may mean different things to different people, depending on the context. In project management, a program usually is a group of related projects and/or services intended to meet a common objective and usually managed by one entity. A program can also indicate a large and complex project that is divided into several projects for more effective management. The PMI defines a program as “Related projects, subsidiary programs, and program activities that are managed in coordinated manner to obtain benefits not available from managing them individually” (PMI, 2017). Programs may include elements of related work outside the scope of the discrete projects in the program.

Programs may be temporary/one‐time or ongoing:

Temporary/one‐time programs

: For example, the City of Paris (France) may include all of the construction projects for the 2024 Summer Olympics under one program. Once this program culminates with the completion of the projects, by the opening of the 2024 Summer Olympic Games, it will be completed and closed. However, the future maintenance of these facilities is a different matter.

Ongoing (usually periodic/annual) programs

: These include projects such as road maintenance and stormwater programs for a public works department in many municipalities. Many private and public institutions have maintenance programs for their existing facilities. Such programs usually have an annual budget and cover numerous small projects—as many as the budget allows. The programs usually live as long the facility does.

One important note: in the United Kingdom, as well as in some other countries that use British terminology, the schedule (timeline) of the project is called a program (spelled programme). This is not the same type of program that we are discussing.

Portfolio

: This is a group of projects, not necessarily related or dependent, that is, usually under one project manager or department. The PMI defines it as “projects, programs, subsidiary portfolios, and operations managed as a group to achieve strategic objectives” (PMI, 2017).

Project

: Defined earlier.

Subprojects: These are segments of the original project that are divided according to specialty, responsibility, phase, area, or other criteria. To the person in charge of a subproject, the subproject is a project, except that the person has to consider not only the internal relationships among the activities but the external relationships as well (with activities in other subprojects in the same project). For example, in a residential or commercial development project, building the infrastructure may be regarded as a subproject. In fact, building the sewer system in the development can be a subproject (to the entire development project) or even a sub‐subproject (to the infrastructure subproject).

Figure 1.1 demonstrates the structure of programs, portfolios, and projects, and the relationships among them.

Figure 1.1 Programs, portfolios, and projects.

Are Projects Unique?

Some people may think of two construction projects as being identical just because they have the same design. In project management, we may have similar projects, but every project is unique. Differences may occur because of location (soil type, weather conditions, labor market, building codes, unforeseen conditions, etc.), labor skill level, management type and experience, or for other circumstances (and how much Murphy's Law was involved).

Tip Box 1.2

Just because two projects have exactly the same design and perhaps were built by the same contractor doesn't make them identical. They are similar but differences can come from site, location (building code, weather, etc.), workforce, execution conditions, and so on.

Project planning has been defined as “the process of choosing the one method and order of work to be adopted for a project from all the various ways and sequences in which it could be done” (Antill and Woodhead, 1990, p. 8; Callahan, Quackenbush, and Rowings, 2013, p. 2). The PMI defines the Planning Process Group as “those processes required to establish the scope of the project, refine the objectives, and define the course of action required to attain the objectives that the project was undertaken to achieve” (PMI, 2017). Project planning serves as a foundation for several related functions, such as cost estimating, scheduling, project control, quality control, safety management, and others.

The author defines project planning as the comprehensive process of thinking of and preparing for all activities and actions needed to successfully complete a project. This includes but is not limited to defining scope and constraints, performing feasibility studies (financial, legal, and other), and comparing alternative designs and execution methods.

Project planning helps the owner, first, in making the decision whether or not to carry out the project, and second, in better and more efficient execution of the project. Project planning helps the contractor in better and more efficient management of the project. Project planning may and should be done by other project parties: focusing on one's own work as well as aligning it with the project's scope and constraints.

Scheduling is the determination of the timing and sequence of operations in the project and their assembly to give the overall completion time. As mentioned previously, scheduling focuses on one part of the planning effort.

Project planning answers these questions: What is going to be done? How? How much? Where? By whom? When? (in general terms, the project's start and end). Scheduling deals with "when" on a detailed level. Figure 1.2 graphically demonstrates this concept.

Figure 1.2 Planning and scheduling.

In fact, scholars have generally separated planning from scheduling: “CPM separates planning and scheduling, and once project information is collected and expressed as a network plan and activity time estimates assigned, CPM calculations can be made. Planning ceases and scheduling starts when the first computation is performed that shows a project duration. The project duration is then compared with the desired schedule and scheduling begins” (O'Brien and Plotnick, 2009, p. 417).

To get an idea about the relationship between project planning and scheduling, assume that you are planning a family vacation “project” for next summer. Your plan may include considerations such as the following:

Purpose of the trip

Who will go on the trip?

What places do you want to visit? (You would like to visit many places, but your time and monetary resources are limited.)

What is the timeframe for the vacation (just the starting and ending dates)?

What is the total budget for the “project” (including the contingency you did not tell other family members about)?

What types of activities do you want to participate in during the trip? (There might be sharp differences among the family members.)

What means of transportation do you plan to use (your car, a rental car, air, train, bus, RV, etc.)?

What other issues, such as accommodations, food, and clothing, need to be addressed?

The project schedule is simply the itinerary, such as the following:

Leave home in Tampa, Florida, on June 8, 2019.

Arrive in Panama City, Florida, on June 8, 2019.

Leave Panama City on June 15, 2019.

Arrive in Atlanta, Georgia, on June 15, 2019.

Leave Atlanta on June 22, 2019.

Arrive in Gatlinburg, Tennessee, on June 22, 2019.

Return to Tampa home on July 7, 2019.

Note that not only are the plan and the schedule related, but also many of the activities and elements of the plan are interrelated. For example, most of the choices in the plan (length of stay, type of accommodations, type of activities, means of transportation, food, etc.) impact the budget. Since different means of transportation have longer time durations than others, they may affect not only the cost but also the schedule. Clearly, a lack of clarity of scope before the project starts may lead to heated arguments and dissatisfaction among team members later on. In real projects, it may lead to huge budget overruns, schedule delays, different parties' dissatisfaction, and a potential loss of business. Therefore, it is important to have a clear understanding of the project's scope, its constraints and requirements, and the decision‐making process.1 Many issues are at stake in this example, but demonstrating the concept of planning and scheduling is the objective.

It has been proven that good planning results in a high “rate of return” in terms of saving time, money, effort, change orders, claims and disputes, and headaches. In fact, there are many construction professionals who assert that there is an inverse relationship between the time of planning and the time of execution (to a point, of course). Many owners rush the design and construction process because “they don't have time for planning.” In fact, in most cases this is self‐defeating and causes additional delays, costs, and headaches. An old carpenters' saying, “Measure twice and cut once,” embodies this concept well.

Tip Box 1.3

Plan first: Measure twice and cut once!

Project Management Plan

In the context of construction projects, a typical plan for an office building project may include the following:

Scope definition

, such as a five‐story building for commercial use (offices) with a total area of about 30,000 square feet. The location is also part of the planning, although in some cases the exact location may be selected later or a few sites may be mentioned as candidates.

A

schematic

or

conceptual design

. This is not a must but will help in visualizing the project. Also, deciding on the level of finish (economy, average, or luxury) will help in making financial arrangements. The final design may later differ significantly.

A

budget number

(e.g., $6 million). The planner must be aware of all project‐related expenses, such as the cost of land, permits, design fees, construction, and so forth. Depending on how strict it is, the budget may influence or even drive the design choices.

A

time frame

(i.e., when the project is expected to start and end).

Other pertinent information

that may be used to justify the project or clarify some of its aspects. If an investor is doing the planning, a

pro forma

helps predict the rate of return and helps in making the decision as to whether or not to build the project.

The Project Management Institute (PMBOK, 2017) defines a project management plan as “the document that describes how the project will be executed, monitored, controlled, and closed.” It may be summary or detailed and may be composed of one or more subsidiary management plans and other planning documents. The objective of a project management plan is to define the approach to be used by the project team to deliver the intended project management scope of the project. It captures the entire project, covering all project phases, from initiation through planning, execution, and closure.

The level of details of the project management plan depends on several factors: the purpose of the plan, the timing of the plan, and the detailed information available (which is, in part, a function of the timing).

The project manager creates the project management plan following available information such as design/contract documents as well as input from the project team and key stakeholders. The plan should be agreed on and approved by at least the project team and key stakeholders. It is a good practice, used by professional project management and consulting firms, to have a formal project management plan approved in the early stages of the project and applied throughout the project. Many owners (clients) require the contractor to submit a project management plan and have it approved as part of the contract documents.

Many professional organizations have an office dedicated to the project management planning and effort, called a project management office (PMO), which is defined by the PMI as “A management structure that standardizes the project‐related governance processes and facilitates the sharing of resources, methodologies, tools, and techniques” (PMI, 2017).

Tip Box 1.4

Have you ever thought of applying project management principles to your own life?

PROJECT CONTROL

Once a project starts, certain aspects can easily deviate or go astray. This deviation can be overspending, a schedule slippage, a departure from the objective/scope, or something else. It is of utmost importance to know at all times where you stand in comparison to where you planned to be (the baseline) at this time. If you find any variance, you must know the amount and causes of the variance and then take corrective action to get back on track or, at the very least, to minimize the variance. If the variance is positive (i.e., the project is ahead of schedule or under budget), actual performance was probably better than that expected in the baseline plan. This process exemplifies project control. Although the concept of project control may cover all aspects of the plan (budget, schedule, quality, etc.), our main focus in this book is on schedule and budget control, which are related. (Extensive coverage of project control is provided in Chapter 7.)

WHY SCHEDULE PROJECTS?

There are several parties involved in any project (stakeholders). They all need and use project schedules but from different perspectives. Following is a group of reasons why project schedules are needed, from two different perspectives: contractors and owners.

Contractors need project scheduling to:

Calculate the project completion date

: In most construction projects, the general contractor (GC), including subcontractors and other team members, is obligated to finish the project by a certain date that is specified in the contract. The contractor has to make sure that the schedule meets this date or otherwise has to accelerate the project. Some contracts contain clauses for penalties for finishing the project later than contractually required and/or incentives (financial or other) for finishing earlier. Also, the schedule may show the stage of

substantial completion

, when the owner may start occupying and using the facility, while the contractor is still doing the rest of the work.

Calculate the start or end of a specific activity

: Specific activities may require special attention, such as ordering and delivering materials or equipment. For instance, the project manager may need special and expensive equipment to be delivered just in time for installation. Long‐lead items may have to be ordered several months in advance. Delivery of very large items may need coordination or a special permit from the city so that the delivery does not disrupt traffic during rush hour. The schedule must show such important dates.

Coordinate among trades and subcontractors, and expose and adjust conflicts

: In today's construction, the GC's role is mostly to coordinate different subcontractors. The GC may be responsible for allocating the use of a tower crane among subcontractors or to ensure that adequate work space is provided to all workers and personnel on‐site. These tasks are in addition to coordinating activities' relationships, such as when a subcontractor's activity depends on the completion of another subcontractor's activity. For example, the drywall contractor cannot start until the framing has been done; once the drywall is installed, the painter can start painting; and so on.

Predict and calculate the cash flow

: The cash flow diagram shows not only the amounts but the timing of each payment, in or out, as well. The timing of an activity has an impact on the cash flow, which may be an important factor for the contractor (or the owner) to consider when scheduling. He or she may delay the start of certain activities within the available

float

(this term is explained subsequently) to make sure that the cash flow does not exceed a certain cap.

Improve work efficiency

: By properly distributing workers and equipment and having efficient materials management (which is explained in

Chapter 6

), the GC can save time and money.

Serve as an effective project control tool

: Project control must have a solid and sound baseline with which current performance can be compared. Project control is achieved by comparing the actual schedule and budget with the baseline (as planned) schedule and budget (this subject is explained in

Chapter 7

).

Evaluate the effect of changes

:

Change orders (CO)

2

are usually inevitable, but well‐planned projects may have few or minor ones. Change orders may come in the form of a directive, that is, an order to the contractor to make a change, or a request for evaluation before authorization. This change may be an addition, a deletion, or a substitution. Change orders may have an impact on the budget, schedule, or both. Cost estimators estimate the cost of change orders (including the impact on the overhead cost as a result of the schedule change), and schedulers calculate the impact of the change on the project schedule. It is the contractor's responsibility to inform the owner of such an impact on the budget or schedule and obtain the owner's approval.

Prove delay claims

: Construction

delay claims

are common. Contractors must be able to accurately prove their claims against owners (or other parties) using project schedules. In most cases, only a

critical path method (CPM)

schedule may prove or disprove a delay claim, which can be a multimillion dollar one.

Project owners and developers need project scheduling to:

Get an idea of a project's expected finish date

: Before an owner demands that the GC complete the project by a certain date, the owner needs to make sure that it is a feasible and reasonable date. This date is calculated by a CPM schedule, prepared by the owner or the designer, or a consultant hired by the owner. This date is also important to the owner, even before selecting a contractor, to conduct feasibility studies and make financial arrangements.

Ensure contractor's proper planning for timely finish

: Owners may demand a project schedule from the prospective or bidding contractor; however, it is very important for the owner to review such a schedule and make sure that it is reasonably accurate and realistic. The owner's approval of the contractor's prepared schedule may imply a liability on the owner's side.

Predict and calculate the cash flow

: The owner is obligated to make timely progress payments to the contractor and other parties during the life of the project. Failure to do so not only may delay the project and/or incur additional cost but also may—at a certain point—be deemed a breach of contract.

Serve as an effective project monitoring tool

: Both the owner and the contractor must monitor the progress of the work and compare actual progress (as-built, schedule and cost) with the baseline (as‐planned) schedule and budget. The contractor uses this process to detect and correct any deviations and also to prepare progress payments. The owner uses this process to verify the actual work progress and the contractor's payment requests.

Evaluate the effect of changes

: Owners may desire or require change orders. In many instances, owners don't expect or fully appreciate the impact these change orders may have on the schedule and/or budget. It is wise for an owner to determine this impact before making a decision regarding a change order. It is also recommended that owners analyze the contractor's assessment of the change order to make sure that it is fair and reasonable.

Verify delay claims