Critical Path Method ScheduleDevelopment, Review and

Analysis Guidelines

Mike Lehmann, P.E.Texas Department of Transportation

District Construction EngineerSan Antonio District

22August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Presentation OverviewPresentation Overview

Background Information

CPM Guide History

Highlights of the Guide

Where to get the Guide

Future developments

33August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Background InformationBackground Information

TxDOT workload as of June 2005TxDOT workload as of June 2005

�� 1,372 Active Construction Projects1,372 Active Construction Projects

�� $12.4 billion under contract$12.4 billion under contract

SAT district workloadSAT district workload

�� 108 Active Construction Projects108 Active Construction Projects

�� $994 million under contract$994 million under contract

(1)

(1) Includes some “active” projects that have yet to start and some that have been completed and have yet to be removed from active status.

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Counties of San Antonio DistrictCounties of San Antonio District

55August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

History and BackgroundHistory and BackgroundDevelopment of ExpertiseDevelopment of Expertise

Used CPM since 1988

Used CPM for the resolution of 50+ claims and disputes

Developed and delivered 40+ in-house training classes

CoCo--authored 1993 CPM spec authored 1993 CPM spec

Primary author of 2004 CPM specPrimary author of 2004 CPM spec

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77August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

History and BackgroundHistory and BackgroundDevelopment of the GuideDevelopment of the Guide

Guidelines were Guidelines were

developed and developed and

finalized on finalized on

December 7, 2001December 7, 2001

Guidelines were Guidelines were

posted to TxDOT posted to TxDOT

Website, Website,

December 2001December 2001

88August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

CONSTRUCTION CLAIMS ADVISOR

December 13, 2004 issue

““We recently We recently

stumstumbled on one of the

more practical treatments of this approach at the Texas

DOT website.”

99August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

CONSTRUCTION CLAIMS

ADVISOR

“To the extent that unfamiliarity with the software is an impediment to use of CPM scheduling, these guidelines are a must-read for the project manager or scheduler who wishes to enhance project performance with better schedules. The TIA guidelines also contain valuable tips, even for the experienced scheduler. We strongly suggest downloading the Guidelines (also available at our website) and printing them out on a color printer.”

www.constructionclaims.com

1010August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Highlights of the GuideHighlights of the Guide

Chapter 1Chapter 1 -- Development Of Critical Path Method Schedules For Contract Time Determination

Chapter 2Chapter 2 -- Review Process For Original Schedules

Chapter 3Chapter 3 -- Review Process For Updated or Revised Schedules

Chapter 4Chapter 4 -- Time Impact Analysis Process For CPM Schedules

1111August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Primavera Basics (P3 version 3.1)Primavera Basics (P3 version 3.1)

1212August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Time Determination Basics

Understand The Sequence Of Work And Traffic Control Plan In The PS&E

Calculate/Estimate Quantities Of Work By Phase

Determine Attainable Production Rates

1313August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Schedule Development StepsSchedule Development Steps

1. Break Down The Work Into Distinct Activities

2. Create The New Schedule

3. Set Up The Calendars

4. Set Up Coding

5. Enter Basic Activity Information

6. Add Relationships

7. Run The Schedule Calculations And Trouble-Shoot

1414August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Schedule Development Steps

Set Up The Calendars

Work Week

Holidays

Bad Weather Days

1515August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Schedule Development Steps

Enter Basic Activity Information

Activity ID Number

Description

Duration

Assign Calendar

Assign Coding

1616August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 1Chapter 1Schedule Development Steps

Enter Relationships

Finish to Start (F-S)

Start to Start (S-S)

Finish to Finish (F-F)

Start to Finish (S-F)

1717August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Highlights of the GuideHighlights of the Guide

Chapter 1Chapter 1 -- Development Of Critical Path Method Schedules For Contract Time Determination

Chapter 2Chapter 2 -- Review Process For Original Schedules

Chapter 3Chapter 3 -- Review Process For Updated or Revised Schedules

Chapter 4Chapter 4 -- Time Impact Analysis Process For CPM Schedules

1818August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 2Chapter 2Schedule Review Steps

1. Restore The Schedule

2. Open The File

3. Review The Calendars

4. Review Activity Coding Structure

5. Review Resource Loading, If Required

6. Defining The Critical Path

7. Organizing The Schedule (Layouts)

8. Calculate The Schedule

9. Review Constraints

10. Prepare Plots And Prints

11. Complete The Schedule Review

1919August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 2Chapter 2Schedule Review Steps

Defining The Critical Path

“Total Float Less than” option allows:

� Making all activities show as critical

� Making selected activities show as critical

� Making no activities show as critical

� Using constraints to force float calculations and drive the critical path

Recommend using “Longest Path”

2020August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

2121August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Highlights of the GuideHighlights of the Guide

Chapter 1Chapter 1 -- Development Of Critical Path Method Schedules For Contract Time Determination

Chapter 2Chapter 2 -- Review Process For Original Schedules

Chapter 3 Chapter 3 -- Review Process For Updated or Revised Schedules

Chapter 4Chapter 4 -- Time Impact Analysis Process For CPM Schedules

2222August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 3Chapter 3

Updated Schedule Review ProcessUpdated Schedule Review Process1. Restore The Schedule2. Open The File3. Review The Schedule For Conformance To The

Specifications4. Set Up Target Schedules5. Review Status Of Updated Schedule6. Recalculate The Schedule7. Prepare Plots And Prints8. Decide If The Schedule Has Been Updated Or

Revised9. Document The Schedule Update Status10. Prepare Look-ahead Schedule Plot

2323August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 3Chapter 3

Updated Schedule Review ProcessUpdated Schedule Review Process

Update or Revision?Update or Revision?

A A schedule updateschedule update is defined as the addition of is defined as the addition of actual start dates and/or actual finish dates to actual start dates and/or actual finish dates to activities that have been started and/or activities that have been started and/or completed, and revising the percent complete completed, and revising the percent complete figure or the remaining duration figure for started figure or the remaining duration figure for started activities. activities.

A A schedule revisionschedule revision is defined as adding or is defined as adding or deleting activities, relationships, resources, or deleting activities, relationships, resources, or any other component of the schedule, or any other component of the schedule, or changing durations.changing durations.

2424August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Project Schedule Status ReportProject Schedule Status Report

Project: STP 2005(01) County: Anywhere

CSJ: 0001-01-001 Contractor: Construction Company, Inc.

Period Cumulative Period Cumulative Calendar Working Explanation for Loss/Gain

Gain/Loss Gain/Loss Gain/Loss Gain/Loss Days Days

GUOR 5/1/2000 11/30/2000 120

GU01 6/1/2000 11/15/2000 109 15 15 11 11 Good production on subgrade widening

GU02 7/1/2000 12/14/2000 112 -29 -14 -3 8 14 0 4 working day delay, Time Suspension

already granted - compare GU02 to GUOR

GU03 8/1/2000 1/26/2001 131 -43 -57 -19 -11

GU3R 8/1/2000 1/30/2001 131 -4 -61 0 -11

GU3D 8/1/2000 2/22/2001 147 -23 -84 -16 -27

GU04 9/5/2000 2/14/2001 145 8 -76 2 -25

GU4A 9/15/2000 3/8/2001 144 -22 -98 1 -24

GU05 10/1/2000 3/8/2001 155 0 -98 -11 -35

GU06 11/1/2000 3/22/2001 163 -14 -112 -8 -43

GU6R 11/1/2000 3/16/2001 163 6 -106 0 -43

GU07 12/9/2000 3/30/2001 169 -14 -120 -6 -49 22 19 ROW Impact - Compare GU07 to GU4A

GU08 1/1/2001 3/30/2001 169 0 -120 0 -49

GU8E 1/10/2001 4/9/2001 159 -10 -130 10 -39

GU09 2/1/2001 5/22/2001 175 -43 -173 -16 -55

GU10 3/1/2001 5/22/2001 167 0 -173 8 -47

GU11 4/1/2001 6/5/2001 174 -14 -187 -7 -54 57 15 Tree CO and Drainage COs, ongoing, may

be until next update before finalized,

compare GU11 to GU8E

Calendar Days Working Days TxDOT LossSchedule

NameData Date

Completion

Date

Working

Days

2525August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Highlights of the GuideHighlights of the Guide

Chapter 1Chapter 1 -- Development Of Critical Path Method Schedules For Contract Time Determination

Chapter 2Chapter 2 -- Review Process For Original Schedules

Chapter 3Chapter 3 -- Review Process For Updated or Revised Schedules

Chapter 4Chapter 4 -- Time Impact Analysis Process For CPM Schedules

2626August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 4Chapter 4Time Impact AnalysisTime Impact Analysis

Types of Time Impact AnalysesTypes of Time Impact Analyses

The As-Planned Impacted Schedule Analysis

The As-Built But-For Schedule Analysis

The Contemporaneous Schedule Analysis

2727August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 4Chapter 4

Time Impact AnalysisTime Impact Analysis

Time Impact Analysis Steps Time Impact Analysis Steps –– Contemporaneous Contemporaneous ApproachApproach

1. Determine the status of the project immediately before the impact begins.

2. Predict the effect of the impact on the project completion date.

3. Track the status of the project during the impact.

4. After the impact is over, determine the status of the project and compare it to the status before the impact began.

2828August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Chapter 4Chapter 4

Time Impact AnalysisTime Impact Analysis

Time Impact Analysis Steps Time Impact Analysis Steps –– Two Different Two Different

ApproachesApproaches

1.1. PrePre--Impact TIA Impact TIA

� Includes Steps 1 and 2 only

2.2. PostPost--Impact TIAImpact TIA

�� Includes Steps 1, 2, 4 and possibly 3 if Includes Steps 1, 2, 4 and possibly 3 if

impact is long durationimpact is long duration

2929August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Where to get the GuideWhere to get the Guidehttp://www.dot.state.tx.us/cst/construction_strategies.htm

3030August 2005August 2005 AASHTO SOC, Mike Lehmann, P.E.AASHTO SOC, Mike Lehmann, P.E.

Future DevelopmentsFuture Developments

Planned Revision for 2004 Spec BookPlanned Revision for 2004 Spec Book

Possible conversion to P3 e/cPossible conversion to P3 e/c

Addition to SAT District Construction Addition to SAT District Construction

Office Intranet Website, along with other Office Intranet Website, along with other

toolstools

Questions?Questions?

Mike LehmannMike Lehmann

(210) 615(210) 615--61006100

mlehman@dot.state.tx.usmlehman@dot.state.tx.us

Thank You!Thank You!