Developing a knowledge-based expert system to determine contract duration for highway construction

323 Pages·1994·10.7 MB·English

by  Chen, Wei-Tong

DEVELOPING A KNOWLEDGE-BASED EXPERT SYSTEM TO DETERMINE
CONTRACT DURATION FOR HIGHWAY CONSTRUCTION
By
WEI-TONG CHEN
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF
THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1994
Dedicated to my parents, my wife, and my family members.
ACKNOWLEDGEMENTS
I would like to express my sincere appreciation to those
persons whose assistance made completion of my research
possible. My supervisory committee chairman, Dr. Zohar
Herbsman, has been a continuing source of knowledge and ideas,
providing focus and guidance throughout the study. Dr. Ralph
D. Ellis, cochairman ofmy supervisory committee, consistently
supported and guided this research. Dr. Ronald A. Cook and
Dr. Charles Kibert served on my committee, providing valuable
comments and suggestions.
Finally, I wish to acknowledge the continuous care and
unconditional support of my parents, my wife, and family
members. I thank them and dedicate this work to them.
iii
TABLE OF CONTENTS
page
ACKNOWLEDGEMENTS iii
LISTOFTABLES viii
LIST OF FIGURES xi
ABSTRACT XV
CHAPTERS
1 INTRODUCTION AND PROBLEM STATEMENT 1
An Overview of the Highway System in the USA 1
Definition of the Contract Duration 7
Measuring Contract Duration 10
ProblemStatement 12
ResearchObjectives 13
ResearchMethodology 15
Literature Survey 16
Knowledge Extracting and Analyzing 16
SystemDevelopment 17
SystemValidation 17
Research Scope 17
Organization of the Dissertation 18
2 REVIEW OF THE LITERATURE 19
Introduction 19
Current Practices of Contract Duration
Determination 19
Methods Used by SHAs for Contract Duration
Determination 23
The Use of the Conventional Approach 25
The Use of the Innovative Approach 42
Using the KBES in the Construction industry 49
Applying the KBES for Construction Planning and
Scheduling 50
Summary of KBES Review 58
Conclusions of Literature Review 61
IV
3
FACTORS AFFECTING CONTRACT DURATION DETERMINATION.. 62
Introduction 62
FacGteonresraAlfSfteactteimnegntContract Duration Determination.. 6633
Geophysical Factors 66
Project Characteristic Factors 72
Construction Operations Factors 74
Legal and Economic Factors 81
Miscellaneous Factors 83
Summary 86
4 AN OVERVIEW OF THE KBES 88
Introduction 88
Basic Structure of KBES 89
Control Strategies 91
ForwardChaining 91
BackwardChaining 92
KnowledgeRepresentation 95
PredicateCalculus 95
Semantic NetworkRepresentation 95
Frame-BasedRepresentation 97
Rule-BasedRepresentation 98
BlackboardRepresentation 98
The Strength and Shortcomings of KBES 100
KBESShells 101
Steps in Developing a KBES 103
Summary 105
5 KNOWLEDGE ACQUISITION FOR DEVELOPING A KBES FOR
CONTRACT DURATION DETERMINATION 106
Introduction 106
KnowledgeAcquisitionApproaches 107
Interviewing 107
Observation 108
Types and Sources of Knowledge 109
Publications 110
Guidelines 110
SchedulingExperts 110
Knowledge Acquisition for EXCONDD Ill
FamiliarizationPhase 112
ElicitationPhase 113
OrganizationPhase 115
Summary 119
6 DEVELOPING A KBES FOR CONTRACT DURATION
DETERMINATION 120
Introduction 120
Selecting a Commercial Shell for EXCONDD 120
V
Evaluation of the KBES Shells 121
Overview of EXSYS Professional 123
Developing the Parametric Time Estimating Module... 126
Developing the Production Rates Module 130
Creating the Database Files 132
Creating the Project Contract Duration Influence
FactorsTemplate 135
Creating the Major Work Duration Calculation
Template 136
Selecting a Scheduling Software 139
Developing the "A+B" Module 139
Forming the Decision Trees for EXCONDD 140
Representing the Knowledge Contained in EXCONDD.... 143
Integration of the Developing Modules 145
Summary 149
7 VALIDATION OF THE DEVELOPING SYSTEM 150
Introduction 150
Validating the PTE Module 151
PTE Module Case Study 1 151
PTE Module Case Study II 152
Validating the Production Rates Module 154
Production Rates Module Case Study I 154
Production Rates Module Case Study II 159
Validating the "A+B" Module 164
"A+B" Module Case Study I 164
"A+B" Module Case Study II 165
Summary 167
8 SUMMARY AND CONCLUSIONS 169
ResearchObjectives 169
Summary 169
Conclusions 171
Future Refinement of the Developed System 173
Expanding the System Knowledge Base 174
Creating a User Interface Program 174
Utilizing the Windows Version EXSYS Shell 175
Recommendations for Future Research 176
Standardizing the Content of Work Production
CRoantdeusctDiantgabRaesseearch on the Impact Measurement o'.f. 176.
the Contract Duration Influence Factors 176
Developing Similar Approach for Other Types of
Construction t 176
APPENDICES
A NATIONWIDE QUESTIONNAIRE SURVEY 179
B QUESTIONNAIRES OF STRUCTURED INTERVIEWS 185
VI
C CONTRACT DURATION ESTIMATION USING THE PTE
APPROACH 189
D CONFIGURATION FILES OF EXCONDD 193
E PROGRAM INTRODUCTION, QUALIFIERS, CHOICES AND
VARIABLES 198
F KNOWLEDGE BASE RULES 232
REFERENCES 301
BIOGRAPHICALSKETCH 306
vii
LIST OF TABLES
1-
2-
TABLE Page
1-1 Expenditure Needs for Rehabilitating Interstate
Highways from 1985-2000 6
2 Comparison of Various Time Units 10
1 Current Practices of Contract Duration
Determination 22
2-2 Partial List of Production Rates Used by the
2- Louisiana SHAs 26
23--3 Project Bid Tabulation Using the "A+B" Method 44
2-4 Current Application of the "A+B" Method 45
2-5 Project Bid Tabulation Using the Lane Rental
Method 46
2-6 Various Daily I/D Rates Used by the New Jersey DOT. 48
2-7 Summary of Various KBES Used in Construction
Planning and Scheduling 59
8 General Characteristics of Surveyed KBES 60
1 Factors Affecting Contract Duration Determination.. 65
3-2 Effect of Cold Weather Conditions on Highway
ConstructionOperations 67
3-3 Annual Working Days Utilized by the Alabama SHAs... 68
3-4 Winter Shutdown Periods Used by Different SHAs 69
3-5 Effect of Project Location on Various Production
Rates 71
3-6 Effect of Different Project Type on Various
ProductionRates 73
viii
3-7 Policy of Assigning Extra Time for Utilities
Relocation 76
33--8 Time Allowances for Mobilization Utilized by
Various SHAs 80
4-
35--9 Effect of Project Size on Various Production Rates. 84
10 Adjusted Factors Used by the Maryland SHAs for
Contract Duration Determination 85
5-1 Comparison of the Conventional Programs and KBES... 89
6-1 General Procedures of Estimating Contract Duration
for Highway Construction Projects 116
5-2 Interrelationships of Contract Duration Influence
Factors and Work Items of a Widening Projects 117
3 Adjusted Factors of Project Complexity for the PTE
Approach 118
1 Comparison of Various Expert System Shells 122
6-2 Various Confidence Systems Included in EXSYS
Professional 125
6-3 The PTE Contract Duration Calculation Template 128
6-4 Summary of Engineer News Records Construction Cost
Index 129
6-5 Template to Store Production Rates of Quantity
Associated Work Items and to Compute Unadjusted
WorkingDay 133
6-6 Template to Store Production Rates of Non-Quantity
Associated Work Items and to Compute Unadjusted
WorkingDay 134
6-7 Summary of Project Contract Duration Influence
Factors 135
6-8 Template of Project Major Work Items and Their
Durations 137
6-9 List of the Project Major Works 138
6-10 Variables Assignment for Influence Factors
AffectingWork Production Rates 144
ix
7-1 Work Dependency of the Production Rates Module
Case Study 1 155
7-2 Allocation of Significant Influence Factors for
the Production Rates Module Case Study I 156
7-3 Work Dependency of the Production Rate Module Case
StudyII 160
7-4 Allocation of Significant Influence Factors for
the Production Rates Module Case Study II 161
7-5 Bids Tabulation for 1-85 Project 164
7-6 Bids Tabulation for 1-77 Project 166
7-7 Summary of Results of System Validation 167
X