This revised and updated edition of Construction Equipment Management fills a gap on this subject by integrating both co
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English Pages 386 [387] Year 2019
Table of contents :
Cover
Half Title
Title Page
Copyright Page
Table of Contents
List of Illustrations
Preface
Chapter 1: Introduction
Importance of Construction Equipment
Construction Equipment Management
Equipment Selection Factors
Construction Equipment Utilization
Organization of This Book
Chapter 2: Time Value of Money
Introduction
Equivalence Concept
Single Payments
Uniform Series of Payments
Cash Flow Diagrams
Alternative Analysis
Rate of Return Analysis
Problems
Chapter 3: Depreciation Accounting Techniques
Introduction
Straight-Line Method
Sum-of-the-Years Method
Declining-Balance Method
Comparison and Uses
Problems
Chapter 4: Ownership and Operating Costs
Introduction
Ownership Costs
Operating Costs
Use of Manufacturers’ Data
Cost Accounting
Unit Cost Determination
Problems
References
Chapter 5: Fundamentals of Soils
Introduction
Soil Properties
Swell and Shrinkage
Optimum Moisture Content and Compaction
Soil Stabilization
Problems
Chapter 6: Fundamentals of Earthmoving
Introduction
Rolling Resistance
Grade Resistance
Total Resistance
Drawbar Pull
Rimpull
Effects of Altitude
Traction
Equipment Performance
Problems
References
Chapter 7: Dozers
Introduction
Types and Uses of Dozers
Dozer Attachments
Production Estimation
Technology Innovation
Cost and Time Analysis
Problems
Chapter 8: Loaders
Introduction
Types and Uses of Loaders
Loader Buckets
Other Loader Attachments
Production Estimation
Cost and Time Analysis
Problems
References
Chapter 9: Scrapers
Introduction
Types and Uses of Scrapers
Push-Loading Scrapers
Production Estimation
Cost and Time Analysis
Problems
References
Chapter 10: Excavators, Draglines, and Clamshells
Introduction
Hydraulic Front Shovel Excavators
Hydraulic Backhoe Excavators
Other Excavator Attachments
Draglines
Clamshells
Cost and Time Analysis
Problems
References
Chapter 11: Trenchers
Introduction
Open-Cut Trench Excavation
Types and Uses of Trenchers
Production Estimation
Cost and Time Analysis
Problems
References
Chapter 12: Trucks and Haulers
Introduction
Types and Uses of Trucks and Haulers
Production Estimation
Balancing Loading and Hauling Productivity
Cost and Time Analysis
Problems
References
Chapter 13: Graders
Introduction
Operation and Uses of Graders
Production Estimation
Technology Innovation
Cost and Time Analysis
Problems
Chapter 14: Soil Stabilizers
Introduction
Types and Uses of Soil Stabilizing Equipment
Production Estimation
Cost and Time Analysis
Problems
Chapter 15: Soil Compactors
Introduction
Types and Uses of Compactors
Production Estimation
Cost and Time Analysis
Problems
Chapter 16: Lifting and Loading Equipment
Introduction
Forklifts
Telescopic Material Handlers
Boom Trucks
Mobile Elevating Work Platforms
Problems
Chapter 17: Cranes
Introduction
Crane Safety
Hydraulic Cranes
Lattice-Boom Cranes
Tower Cranes
Gantry Cranes
Launching Gantry Cranes
Problems
Reference
Chapter 18: Shaft Drilling and Pile Driving
Introduction
Drilled Shaft Construction
Drilling Equipment
Pile Construction
Pile-Driving Equipment
Production Estimation
Cost and Time Analysis
Problems
Chapter 19: Trenchless Equipment
Introduction
Horizontal Directional Drilling
Microtunneling
Pipe Bursting and Sliplining
Problems
Reference
Chapter 20: Concrete Equipment
Introduction
Concrete Production
Structural Concrete
Concrete Handling Equipment
Concrete Pavements
Concrete Paving Equipment
Production Estimation
Cost and Time Analysis
Problems
Chapter 21: Pumping Equipment
Introduction
Types of Pumps
Pump Selection
Effect of Altitude
Well-Point Systems
Cost Analysis
Problems
Reference
Chapter 22: Asphalt Equipment
Introduction
Asphalt Pavements
Asphalt Construction Techniques
Types of Asphalt Equipment
Production Estimation
Cost and Time Analysis
Problems
Chapter 23: Operation Analysis
Introduction
Task Identification
Equipment Identification
Equipment Selection
Cost Analysis
Problems
Glossary
Appendices A – Dimensional Analysis
Appendices B – Conversion Factors
Appendices C – Interest Tables
Index
CONSTRUCTION EQUIPMENT MANAGEMENT
This revised and updated edition of Construction Equipment Management fills a gap on this subject by integrating both conceptual and hands-on quantitative knowledge on construction equipment into a process that facilitates student learning. The first six chapters summarize interdisciplinary concepts that are necessary to ground students’ learning on construction equipment management, including both engineering and economics. Each of the next 16 chapters covers a different type of construction equipment and associated methods of use. The final chapter introduces the more advanced concept of operational analysis. This allows the book to be used on numerous courses at different levels to prepare graduates to apply skills on construction equipment when planning for a new project, estimating its costs, and monitoring field operations. Organized around the major categories of construction equipment, including both commercial and heavy civil examples, case studies, and exercises, this textbook will help students develop independence in applying concepts to hands-on scenarios. A companion website provides an instructor manual, solutions, additional examples, lecture slides, figures, and diagrams. John E. Schaufelberger is the Dean of the College of Built Environments at the University of Washington, USA. He is the co-author of Management of Construction Projects, published by Routledge. Giovanni C. Migliaccio is an Associate Professor in Construction Management at the University of Washington, USA. He is also the Executive Director for the University of Washington Center for Education and Research in Construction, holds a P.D. Koon Endowed Professorship and an affiliate fellowship with the University of Washington Runstad Center for Real Estate Studies. He is the co-author of Introduction to Construction Project Engineering, also published by Routledge.
CONSTRUCTION EQUIPMENT MANAGEMENT Second Edition
John E. Schaufelberger and Giovanni C. Migliaccio
Second edition published 2019 by Routledge 2 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN and by Routledge 52 Vanderbilt Avenue, New York, NY 10017 Routledge is an imprint of the Taylor & Francis Group, an informa business 2019 John E. Schaufelberger and Giovanni C. Migliaccio The right of John E. Schaufelberger and Giovanni C. Migliaccio to be identified as authors of this work has been asserted by them in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. First edition published by Prentice Hall 1998 British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging-in-Publication Data Names: Schaufelberger, John, 1942- author. | Migliaccio, Giovanni C. (Giovanni Ciro), 1968- author. Title: Construction equipment management / John Schaufelberger and Giovanni C. Migliaccio. Description: Second edition. | Abingdon, Oxon : Routledge, 2019. | Includes bibliographical references and index. Identifiers: LCCN 2018051854| ISBN 9780815360827 (hardback) | ISBN 9780815360834 (pbk.) | ISBN 9781351117463 (ebook) Subjects: LCSH: Construction equipment—Management. | Engineering—Equipment and supplies—Management. | Construction industry--Management. Classification: LCC TA213 .S34 2019 | DDC 690.028/4—dc23 LC record available at https://lccn.loc.gov/2018051854 ISBN: 978-0-8153-6082-7 (hbk) ISBN: 978-0-8153-6083-4 (pbk) ISBN: 978-1-351-11746-3 (ebk) Typeset in Bembo by Swales & Willis Ltd, Exeter, Devon, UK Visit the companion website: www.routledge.com/cw/schaufelberger
CONTENTS
List of Illustrations xi Preface xviii 1 Introduction 1 Importance of Construction Equipment 1 Construction Equipment Management 1 Equipment Selection Factors 2 Construction Equipment Utilization 3 Organization of This Book 4 2 Time Value of Money 5 Introduction 5 Equivalence Concept 5 Single Payments 6 Uniform Series of Payments 8 Cash Flow Diagrams 10 Alternative Analysis 12 Rate of Return Analysis 15 Problems 19 3 Depreciation Accounting Techniques 21 Introduction 21 Straight-Line Method 21 Sum-of-the-Years Method 22 Declining-Balance Method 24 Comparison and Uses 26 Problems 26 4 Ownership and Operating Costs 29 Introduction 29 Ownership Costs 29
vi Contents
Operating Costs 32 Use of Manufacturers’ Data 38 Cost Accounting 38 Unit Cost Determination 43 Problems 47 References 50 5 Fundamentals of Soils 51 Introduction 51 Soil Properties 51 Swell and Shrinkage 57 Optimum Moisture Content and Compaction 61 Soil Stabilization 64 Problems 66 6 Fundamentals of Earthmoving 69 Introduction 69 Rolling Resistance 69 Grade Resistance 71 Total Resistance 72 Drawbar Pull 74 Rimpull 74 Effects of Altitude 77 Traction 78 Equipment Performance 79 Problems 83 References 85 7 Dozers 86 Introduction 86 Types and Uses of Dozers 87 Dozer Attachments 88 Production Estimation 89 Technology Innovation 94 Cost and Time Analysis 96 Problems 97 8 Loaders 99 Introduction 99 Types and Uses of Loaders 101 Loader Buckets 102
Contents vii
Other Loader Attachments 102 Production Estimation 103 Cost and Time Analysis 109 Problems 110 References 111 9 Scrapers 112 Introduction 112 Types and Uses of Scrapers 113 Push-Loading Scrapers 118 Production Estimation 120 Cost and Time Analysis 132 Problems 134 References 136 10 Excavators, Draglines, and Clamshells 137 Introduction 137 Hydraulic Front Shovel Excavators 137 Hydraulic Backhoe Excavators 141 Other Excavator Attachments 146 Draglines 146 Clamshells 152 Cost and Time Analysis 156 Problems 158 References 160 11 Trenchers 161 Introduction 161 Open-Cut Trench Excavation 161 Types and Uses of Trenchers 163 Production Estimation 165 Cost and Time Analysis 166 Problems 169 References 170 12 Trucks and Haulers Introduction 171 Types and Uses of Trucks and Haulers 171 Production Estimation 172 Balancing Loading and Hauling Productivity 187
171
viii Contents
Cost and Time Analysis 188 Problems 190 References 193 13 Graders 194 Introduction 194 Operation and Uses of Graders 194 Production Estimation 196 Technology Innovation 200 Cost and Time Analysis 200 Problems 202 14 Soil Stabilizers
204
Introduction 204 Types and Uses of Soil Stabilizing Equipment 204 Production Estimation 206 Cost and Time Analysis 208 Problems 209 15 Soil Compactors
211
Introduction 211 Types and Uses of Compactors 212 Production Estimation 218 Cost and Time Analysis 219 Problems 221 16 Lifting and Loading Equipment 223 Introduction 223 Forklifts 223 Telescopic Material Handlers 225 Boom Trucks 226 Mobile Elevating Work Platforms 228 Problems 228 17 Cranes Introduction 231 Crane Safety 231 Hydraulic Cranes 233 Lattice-Boom Cranes 235 Tower Cranes 241 Gantry Cranes 244
231
Contents ix
Launching Gantry Cranes 246 Problems 246 Reference 249 18 Shaft Drilling and Pile Driving 250 Introduction 250 Drilled Shaft Construction 250 Drilling Equipment 252 Pile Construction 252 Pile-Driving Equipment 254 Production Estimation 257 Cost and Time Analysis 259 Problems 262 19 Trenchless Equipment 264 Introduction 264 Horizontal Directional Drilling 264 Microtunneling 268 Pipe Bursting and Sliplining 271 Problems 271 Reference 272 20 Concrete Equipment
273
Introduction 273 Concrete Production 273 Structural Concrete 274 Concrete Handling Equipment 276 Concrete Pavements 280 Concrete Paving Equipment 281 Production Estimation 284 Cost and Time Analysis 286 Problems 288 21 Pumping Equipment 291 Introduction 291 Types of Pumps 291 Pump Selection 294 Effect of Altitude 306 Well-Point Systems 308 Cost Analysis 308 Problems 310 Reference 312
x Contents
22 Asphalt Equipment 313 Introduction 313 Asphalt Pavements 313 Asphalt Construction Techniques 314 Types of Asphalt Equipment 315 Production Estimation 320 Cost and Time Analysis 324 Problems 326 23 Operation Analysis 329 Introduction 329 Task Identification 329 Equipment Identification 330 Equipment Selection 331 Cost Analysis 337 Problems 339 Glossary 342 Appendices: A – Dimensional Analysis 346 B – Conversion Factors 350 C – Interest Tables 351 Index 367
ILLUSTRATIONS
Figures 1.1 2.1 2.2 2.3 2.4 2.5 2.6 3.1 4.1 4.2 4.3 4.4 4.5 4.6 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 6.1 6.2 6.3 6.4 7.1 7.2 7.3 7.4
Economic Haul Distance for Mobile Construction Equipment Cash Flow Diagram Cash Flow Diagram Cash Flow Diagram Cash Flow Diagram Cash Flow Diagram Cash Flow Diagram Depreciation Curves for Three Methods of Depreciation Accounting Change in Ownership and Operating Costs with Time Cash Flow Diagram Cash Flow Diagram Ownership and Operating Cost Estimating Form Steps in Developing a Direct Cost Estimate for a Work Package Equipment Project Cost Components Primary Soil Components Soil Gradation Curves Sieve Analysis Determination of Soil Plasticity Unified Soil Classification System Plasticity Chart Soil Volume Change During Excavation and Compaction Proctor Test Nuclear Testing of Soil Density Variation of Dry Density with Moisture Content Rolling Resistance Grade Resistance and Rimpull Performance Chart for Tracked Dozer Performance Chart for Wheeled Scraper Tracked Dozer Wheeled Dozer Performance Chart for Tracked Dozer Performance Chart for Wheeled Dozer
4 11 13 14 14 16 18 27 30 32 36 39 44 46 52 53 54 54 55 59 61 62 63 70 72 75 76 86 87 88 89
xii Illustrations
7.5 7.6 7.7 7.8 7.9 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8 9.9 9.10 9.11 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 11.1 11.2 11.3 11.4 12.1 12.2 12.3 12.4 12.5 12.6
Various Blades for Tracked Dozers Dozer-Mounted Hydraulically Operated Ripper Configuration of Dozer Blade Load for Different Soil Types Dozer Blade Load Measurements Tracked Dozer with GPS Grade Control Equipment Tracked Loader Articulated Wheeled Loader Loading Dump Truck Rubber Tracked Loader Struck and Heaped Bucket Capacity General Purpose Loader Bucket Multipurpose Loader Bucket Loader with Auger Attachment Loader with Fork Attachment Single-Engine Scraper Twin-Engine Scraper Push-Loading Scrapers Push-Pull Connection Push-Pull Scrapers Loading Elevating Scraper Scraper Elevator Auger Scraper Methods of Push-Loading Scrapers Performance Chart for Elevating Scraper Performance Chart for Single-Engine Scraper Front Shovel Excavating an Embankment Hydraulic Backhoe Excavator Utility Construction with a Backhoe Wheeled Loader with Backhoe Attachment Excavator with Plate Compactor Excavator with Hydraulic Hammer Dragline Mounted on Track-Mounted Crane Clamshell Dredging Granular Material Marine Crane Being Pulled by Tugboat Trench Protection Systems Trench Excavation in Urban Area Wheel Trencher Chain Trencher On-Highway Dump Truck with Trailer Off-Highway Rigid-Frame Dump Truck Off-Highway Articulated Dump Truck End-Dump Hauler Bottom-Dump Hauler Side-Dump Hauler
90 91 91 92 95 99 100 100 101 102 103 104 105 112 113 114 115 115 116 117 118 119 124 129 138 141 142 143 146 147 148 153 154 162 163 164 165 172 173 174 174 175 175
Illustrations xiii
12.7 12.8 13.1 13.2 13.3 13.4 14.1 14.2 14.3 15.1 15.2 15.3 15.4 15.5 15.6 15.7 15.8 15.9 16.1 16.2 16.3 16.4 16.5 16.6 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 17.9 17.10 17.11 17.12 17.13 17.14 18.1 18.2 18.3 18.4 18.5
Performance Chart for Off-Highway Articulated Dump Truck Retarder Performance Chart for Off-Highway Articulated Dump Truck Grader with Ripper Shaping a Bank Grader with Tilted Front Wheels Area Grading Using the (a) Back-and-Forth and (b) Looping Methods Grader with GPS Control Rotary Mixer Operation of Rotary Mixer Soil Stabilization with Asphalt Water Truck Pneumatic-Tire Compactor Smooth Steel-Drum Compactor Tamping-Foot Compactor Vibratory Smooth-Drum Compactor Vibratory Tamping-Foot Compactor Walk-Behind Tamping-Foot Compactor Vibratory Ram Compactor Vibratory Plate Compactor Forklift Transporting Construction Material Telescopic Material Handler Rated Lift Capacity for Caterpillar TH103 Telescopic Material Handler Boom Truck Scissor Lift Supporting a Worker Multiple Telescopic Booms Supporting Workers Chain Sling for Lifting Load Crane Lift Plan Single-Engine Hydraulic Crane Two-Engine Hydraulic Cranes Setting Bridge Girders Fully Extended Outriggers on Truck-Mounted Hydraulic Crane Two Crawler-Mounted Lattice Boom Cranes Working in Tandem Truck-Mounted Lattice Boom Crane Horizontal Jib Tower Crane Self-Erecting Tower Crane Luffing Jib Tower Crane Articulated Jib Tower Crane Gantry Crane Launching Gantry Crane Setting Precast Bridge Segments with a Launching Gantry Crane Secant Pile Construction Completed Secant Pile Wall Shaft Drilling for Drilled Pier Typical Setup for Pile Testing Driving Concrete Pile with Diesel Hammer
177 178 194 195 196 200 205 205 206 212 213 214 215 215 216 216 217 218 224 225 226 227 229 230 232 234 235 236 237 238 239 241 242 243 244 246 247 247 251 251 253 254 255
xiv Illustrations
18.6 18.7 18.8 19.1 19.2 19.3 20.1 20.2 20.3 20.4 20.5 20.6 20.7 20.8 20.9 20.10 20.11 20.12 21.1 21.2 21.3 21.4 21.5 21.6 22.1 22.2 22.3 22.4 22.5 22.6 22.7 22.8 22.9 22.10 A.1
Driving Circular Steel Piling Close-Up of Diesel Hammer Driving Steel Piling with Vibratory Hammer HDD Main Components HDD System Assisted by Guidance System MTBM Main Components Concrete Slump Test Rear-Discharge Concrete Mixer Truck Placing Concrete with Concrete Bucket Concrete Pump Placing Large Slab Placing Concrete with Powered Concrete Buggy Vibrating Concrete Walk-Behind Power Trowel Riding Power Trowel Concrete Laser Screed Typical Concrete Pavement Structure Concrete Highway Construction with Slip-Form Paver Concrete Curb Construction with Slip-Form Paver Typical Centrifugal Pump Impeller Typical Centrifugal Pump Typical Diaphragm Pump Typical Submersible Pump Submersible Pump Performance Curve Typical Well-Point System Typical Asphalt Pavement Structure Typical Batch-Type Asphalt Plant Typical Drum-Mix Asphalt Plant Asphalt Paver Material Flow in an Asphalt Paver Asphalt Distributor Spreading Aggregate with a Self-Propelled Aggregate Spreader Pneumatic-Tire Compactor Compacting Asphalt Finish Rolling with Steel-Drum Compactor Removing Asphalt Pavement with Milling Machine Soil-Specific State Conversions
256 258 259 265 266 270 275 276 277 278 279 280 281 282 283 283 284 285 292 293 293 295 306 308 313 315 316 316 317 317 318 319 319 320 349
Tables 3.1 3.2 3.3 3.4 4.1
Book Values for Example 3.1 Book Values for Example 3.2 Book Values for Example 3.3(a) Book Values for Example 3.3(b) Types of Ownership and Operating Costs
23 24 25 26 29
Illustrations xv
4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 5.1 5.2 5.3 6.1 6.2 6.3 6.4 6.5 6.6 6.7 8.1 8.2 9.1 9.2 9.3 9.4 9.5 9.6 9.7 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 10.10 10.11 10.12 10.13 10.14
Estimated Useful Life of Construction Equipment in Total Operating Hours Equipment Repair Factors Based on a 10,000-Hour Useful Life Estimated Average Tire Life in Hours of Use Equipment Fuel Factors in Gallons per Horsepower-Hour Equipment Service Cost Factors Summary Results for Example 4.3 Operating Factors for Earthmoving Operations Unit Price Estimation for Embankment in Place Work Package Contractor Historical Cost Records for Problem 4.4 Contractor Historical Cost Records for Problem 4.5 Visual Methods for Identifying Silts and Clays Unified Soil Classification and Symbol Chart Representative Material Properties Representative Rolling Resistances for Various Types of Operating Surfaces Typical Coefficients of Traction Data for Example 6.3 Weight Distribution for Problem 6.2 Manufacturer’s Data for Problem 6.3 Manufacturer’s Data for Problem 6.7 Weight Distribution for Problem 6.8 Representative Bucket Volumes and Weights Loader Bucket Fill Factors Fixed Times for Scrapers Speed Factors for Scrapers Scraper Information for Example 9.2 Variable Time Computation for Example 9.2 Scraper Information for Example 9.3 Variable Time Computation for Example 9.3 Cost Data for Example 9.4 Front Shovel Bucket Fill Factors Shovel Productivity Correction Factor for Depth of Cut and Angle of Swing Operating Factors for Excavating Operations Rated Lifting Capacity for a Hydraulic Backhoe Excavator (in pounds) Backhoe Bucket Fill Factors Average Cycle Times for Hydraulic Backhoes Rated Dragline Lifting Capacity Representative Dragline Bucket Sizes and Weights Ideal Dragline Cycle Time in Seconds Optimal Depth of Cut for Various Size Dragline Buckets Dragline Productivity Correction Factor for Depth of Cut and Angle of Swing Representative Clamshell Bucket Sizes and Weights Rated Clamshell Lifting Capacity Clamshell Productivity Correction Factor for Angle of Swing
30 33 34 34 35 42 45 48 49 50 53 56 58 71 79 80 83 84 84 84 103 106 122 122 123 126 128 131 132 139 140 140 143 144 144 148 149 150 150 151 154 155 155
xvi Illustrations
11.1 11.2 12.1 12.2 12.3 12.4 12.5 12.6 12.7 15.1 16.1 16.2 17.1 17.2 17.3 17.4 17.5 17.6 18.1 18.2 18.3
Hydraulic Backhoe Excavators vs. Trenchers 162 Approximate Trencher Production Rates 165 Fixed Times for Trucks and Haulers 176 Speed Factors for Trucks and Haulers 179 Weight Distribution 180 Variable Time Computation 183 Weight Distribution 184 Hourly Cost Data 188 Weight Distribution 190 Most Efficient Compactor for Different Types of Material 214 Rated Lift Capacity for Typical Forklift 224 Rated Lift Capacity for a Typical Boom Truck 228 Rated Lift Capacity for Hydraulic Crane 237 Rated Lifting Capacity for Crawler Crane with Lattice Boom 240 Rated Lifting Capacity for Horizontal Jib Tower Crane 245 Rated Lifting Capacity for Luffing Jib Tower Crane 245 Crane Lifting Capacity for 36-foot Boom 248 Crane Lifting Capacity for 48-foot Boom 248 Comparison of Pile Hammers 257 Typical Number of Piles Driven per Hour 259 Hourly Rental or Ownership and Operating Costs for Powered Pile Driving Hammers 260 18.4 Estimated Hourly Costs 261 18.5 Estimated Hourly Costs 262 18.6 Estimated Hourly Costs 263 19.1 Comparison of Horizontal Drilling (HDD) Systems 265 20.1 Typical Concrete Admixtures 274 21.1 Pump Selection Table 294 21.2 Equivalent Length of Straight Pipe for Various Fittings and Valves 296 21.3 Equivalent Friction Head in Feet per 100 Feet of Pipe 296 21.4 Equivalent Friction Head in Feet per 100 Feet of Smooth Bore Hose 297 21.5 Determining Equivalent Length of Pipe 298 21.6 Performance Standards for M-Rated Centrifugal Pumps 299 21.7 Performance Standards for MT-Rated Centrifugal Pumps 302 21.8 Performance Standards for MTC-Rated Centrifugal Pumps 304 21.9 Equivalent Suction Lifts for Various Elevations 307 21.10 Correction Factors for Estimating Pump Performance at Various Elevations 307 21.11 Dewatering Cost Data 309 21.12 Labor and Material Costs 311 22.1 Equipment Cost Data 325 22.2 Equipment Cost Data 328 23.1 Equipment Selection 331 23.2 Weight Distribution for Example 23.1 332
Illustrations xvii
23.3 23.4 23.5 23.6 23.7
Variable Time Computation for Example 23.1 Hourly Cost Data for Example 23.2 Weight Distribution for Problem 1 Weight Distribution and Other Equipment Data for Problem 2 Hourly Cost Data for Problem 2
335 337 339 340 341
PREFACE
Knowledge of construction equipment, its use, productivity and cost estimation, and operation analysis are critical skills for construction professionals. When the scope of the first edition of this book was developed 20 years ago, the intent was to provide readers with this knowledge in an easy-to-read format using numerous examples to illustrate major concepts. It was written to be used as a text in undergraduate civil engineering, construction, or construction management courses. It also is suitable as a reference for professional construction managers. This second edition contains updated cost information as well as new and revised content to reflect current developments in the use of construction equipment. Major additions include new chapters on trenchers and trenchless equipment. The book starts with a description of techniques for estimating equipment ownership and operating costs as well as fundamentals of soils and earthmoving. Next, specific types of equipment are discussed and applications for their use are described. Then techniques for estimating equipment productivity and unit costs are presented. The book concludes with a discussion of operation analysis in which the type and number of pieces of equipment are selected to complete specific construction project tasks. Also included are a glossary and appendices with dimensional analysis examples, common conversion factors, and tables of interest factors. The book was developed on the premise that readers have a basic understanding of the construction process, but limited knowledge of construction equipment. Coverage includes all major types of equipment typically used on commercial and highway construction projects. The operational capabilities of each equipment type are described and illustrated with numerous figures. Equipment selection considerations are presented, and techniques for estimating equipment productivity and costs are discussed. Concise explanations of concepts are followed with detailed example problems to illustrate major teaching points. Sample manufacturers’ technical data are provided to illustrate its use. Realistic problems are included at the end of each chapter to reinforce the concepts discussed. A companion website is available to instructors, which includes slide decks and an instructor’s manual containing solutions to all problems. This book could not have been written without the help of many people. We wish to express our deep appreciation to the many equipment manufacturers who graciously permitted publication of the photographs and technical data contained in the book. John E. Schaufelberger Giovanni C. Migliaccio
1 INTRODUCTION
Importance of Construction Equipment Construction equipment plays an important role in most construction projects. Whether it be to prepare the site, erect a building or bridge, or construct an airport runway, use of construction equipment is essential in completing construction projects. Commercial or residential contractors typically rely on renting or leasing equipment as needed, or they may choose to subcontract the work. However, because of repeated use of many major pieces of equipment, heavy civil construction contractors often find it more cost-effective to own their own equipment and treat their equipment fleet as a profit center for their companies. A contractor’s approach toward equipment is easily identifiable by reviewing their balance sheet, where equipment usually represents a large portion of the assets for heavy civil contractors and earthmoving specialty contractors. On the other hand, equipment ownership is modest among building contractors and homebuilders. Decisions regarding the types and quantity of equipment to use on a project will greatly impact the project cost and duration. Consequently, the construction manager needs to select the equipment combination that yields the lowest production cost while achieving the desired productivity to enable meeting the contractual completion date. Thus, it is important for construction managers to understand the types of equipment used in construction, how they are used, safety considerations with their use, and how to estimate production costs.
Construction Equipment Management Equipment is a critical resource in the execution of most construction projects. As the equipment fleet may represent the largest long-term capital investment in many construction companies, equipment management decisions have significant impacts on the economic viability of these construction firms. Equipment must pay for itself by earning more for the contractor than it costs to purchase, own, and use it. Idle equipment is a drain on income – operating costs are incurred only when the equipment is used, but ownership costs are incurred irrespective of frequency of use. Contractors must continually evaluate their equipment fleets to determine when to acquire additional items, when to replace items, and when to dispose of items that are underutilized. One of the key decisions in planning and executing a construction project is the selection of equipment to use on the project. The type of equipment chosen will determine how the work will be done, the time required to complete the work, and the cost of construction. Therefore, it is important that construction managers understand what type of construction equipment is most appropriate for each
2 Introduction
construction task and how to estimate equipment productivity and costs. Success in construction is greatly influenced by the selection of equipment for the tasks to be performed. The capabilities of construction equipment are described in manufacturers’ literature and can be used to estimate equipment productivity. The costs to be considered are the cost of owning, leasing, or renting the equipment and the costs of operating, maintaining, and repairing it. The effectiveness of a contractor’s preventive maintenance program will significantly influence equipment operating and repair costs.
Equipment Selection Factors Most construction operations can be performed by more than one type of equipment. The equipment selected should complete the work in accordance with the project plans and specifications, in the required time frame, and at the least overall cost. The following factors should be considered in selecting equipment for a project: •
•
Cost-effectiveness. This means not only selecting the appropriate type of equipment for the task, but also selecting an appropriately sized machine.This involves comparison of the increased production rates of larger machines with their increased ownership and operating costs. Where possible, contractors should select the size of equipment that minimizes the unit cost (e.g., dollars per cubic yard) of performing the construction task.The soil conditions of the job site may dictate the type of equipment that should be selected. Tracked equipment usually is selected when the job site is soft or wet, because they exert less ground pressure and generally have better traction than wheeled equipment under such conditions. Construction site access or working area restrictions may limit the types and sizes of equipment that can be used on a construction site. The necessity to traverse highways will limit the use of off-highway equipment. Versatility. To control total project costs and minimize equipment transportation costs, equipment should be selected that can perform multiple tasks on a given project site. Using a dozer to excavate for a foundation, backfill the completed foundation, and carry out rough grading around the newly constructed building is usually more efficient than using a different type of equipment for each task. The project must be analyzed in its entirety to select the most cost-effective set of construction equipment to be used on the project. The basic criteria that should be used in selecting equipment for specific tasks are:
• • • • • • •
The capability of the equipment to perform the work The capability of the equipment to perform effectively under the working conditions of the job site The availability of the equipment, either from the contractor’s equipment fleet or from a rental or leasing agency The reliability of the equipment and predicted maintenance requirements The availability of parts and service support for the equipment The capability of the equipment to perform multiple tasks on the project Safety features available with the equipment
Selection involves the type and size of equipment, and its manufacturer. If the contractor owns a fleet of equipment, the choice might be limited to equipment that is available at the time needed. If the
Introduction 3
equipment is to be rented or leased, there may be a wider selection from which to choose. Generally, contractors select the set of equipment for a project that minimizes the unit cost (e.g., dollars per cubic yard) of performing the required work. Mobilization and demobilization costs also must be considered, and a set of multifunctional equipment might represent the best choice to minimize mobilization and demobilization costs.
Construction Equipment Utilization Each piece of construction equipment is specifically designed by the manufacturer to perform specific mechanical operations. The job of the construction manager is to match the right piece of equipment or combination of equipment to the individual tasks to be performed in completing the project. One of the critical steps to determine the cost effectiveness of an equipment item is productivity estimation. Leading to equipment selection, this step is necessary to ensure that both cost and schedule implications are considered. Equipment production is work performed and is typically measured in volume, area, or linear length of work performed in a unit of time, such as an hour. Although each major type of equipment has different operational characteristics, it is not always obvious which type of equipment is best suited to a particular project task. After studying the contract plans and specification, a soils report, and the project site, the construction manager must visualize how to employ specific pieces of equipment to accomplish the work. A quantity take-off is needed to determine the quantity of work to be performed, and an initial plan should be developed to prepare a list of equipment that will be needed for the project. Sometimes, multiple options need to be considered, and unit cost data developed for more than one option. Site conditions may limit the number of options that can be considered. For example, if excavated materials are to be transported off site over a highway, trucks will be needed because scrapers are not allowed to operate on highways. Earthmoving tasks typically involve some combination of excavating, loading, hauling, spreading, compacting, and grading. Excavating can be performed with a dozer, a loader, an excavator, a front shovel, a clamshell, a dragline, or a scraper. The best choice depends on the work requirements of the project. The dozer can dig and push the excavated material out of the way. The scraper can load itself and haul the material away. Trucks can be loaded and used to haul the excavated material to a dump site. Loading is done with a loader, a shovel front, a clamshell, a dragline, or an excavator. Hauling is done either with trucks, haulers, or scrapers. Spreading usually is done by a scraper, dozer, or grader. Compacting is done with one of the many types of compactors manufactured. Grading is done with a grader. The conditions of the project site and the haul distances often dictate the type of equipment to use. Because of its greater traction, tracked equipment is used where the site is wet. Equipment selection is based on an analysis of the haul distance, underfoot conditions, grades, material type, production rate, and operator skill. Distance is used as the basis for initial equipment selection. The economic haul distances (one way) for different types of mobile construction equipment are shown in Figure 1.1. The cross-hatched portions of the bars represent the most economical haul distances for the indicated systems. This figure can be used for initial selection of the appropriate type of hauling equipment. Once the type of equipment has been selected, the contractor must select the size to use. The alternatives may be limited by the contractor’s equipment fleet or what is available from a rental or leasing agency. Larger equipment generally has higher productivity than smaller models, but it also costs more to own or rent and operate. The labor costs generally are similar irrespective of the size of equipment selected, but the rental and other operating costs will increase with larger models. The contractor should
4 Introduction
FIGURE 1.1
Economic Haul Distance for Mobile Construction Equipment
(Courtesy of Caterpillar Inc.)
attempt to select the size of equipment that will perform the required tasks at the least cost. This involves determining a unit cost for each activity, considering the equipment productivity and the hourly ownership or rental, operating, and labor costs.
Organization of This Book The purpose of this book is to provide the student with (1) an understanding of the basic issues involved in construction equipment management and (2) an ability to estimate equipment productivity and cost. Concepts are discussed at the beginning of each chapter, followed by example problems illustrating the concepts introduced. A set of problems is provided at the end of most chapters to give students an opportunity to apply the concepts discussed. Chapters 1 to 6 provide introductory concepts. Chapters 2, 3, and 4 are devoted to learning techniques for estimating equipment ownership and operating costs. Chapter 5 discusses relevant soil properties, and Chapter 6 introduces students to the fundamentals of earthmoving. Chapters 7 to 22 are devoted to learning the capabilities of specific types of equipment and methods for estimating productivity and cost data. Chapter 23 concludes by addressing operation analysis. Dimensional analysis is discussed in Appendix A, common conversion factors are in Appendix B, and interest tables are in Appendix C. A glossary of terms and an index are also included.
2 TIME VALUE OF MONEY
Introduction The value of a sum of money will change over time. Its value will increase because of interest earned if invested or deposited in a bank, while its value will decrease because of interest that must be paid to a lending institution, such as a bank, for borrowing the money. For example, $1,000 invested in a savings account at an interest rate of 5% will have a value of $1,050 after one year. However, if you borrow $1,000 from a bank for one year at a 5% interest rate, you must repay the loan at the end of the year at a cost of $1,050. The other factor that influences the value of money is the rate of inflation, which is a result of national monetary policy. We will ignore the rate of inflation in our discussion in this book, but it can be considered when selecting an interest rate to use for economic analysis. In our analysis, we will assume a zero rate of inflation and a constant interest rate over the period of analysis. Because of the cost of money, interest must be considered by contractors when making decisions regarding their equipment. This requires a cash flow analysis which recognizes that money has a different economic value depending on when it is received or paid. Contractors continually analyze their equipment fleets to ensure that none of their equipment is losing money for them. Major company decisions include purchasing, leasing, depreciating, repairing, and replacing equipment. These management decisions are based on economic analysis of each alternative course of action. The time value of money must be considered in order to make the best decisions.
Equivalence Concept The concept of equivalence means that payments differing in magnitude but made at different time periods may be equivalent to one another. The interest factors described in the following two sections can be used to determine the equivalent value of money at a time period different from the one in which the money is paid or received. This involves consideration of time and the interest rate. For example, a contractor might be interested in purchasing a truck in five years and wants to determine how much he or she should invest today to have sufficient funds at the end of the five-year period. Another example might be a contractor who is considering whether to purchase or to lease a crane. Each alternative has differing costs that are incurred at different times. To compare both alternatives, the contractor decides to determine an equivalent cost for each alternative based on its present worth, which means determining an equivalent cost at today’s value. To be meaningful, any economic comparison must be based on equivalent costs at the same point in time. In other words, comparing a future cost of one alternative with the present worth cost of a second alternative is not valid and therefore not meaningful.
6 Time Value of Money
Single Payments Single payments may occur either today or at some time in the future. P is used to indicate a sum paid or received today, that is, a present sum of money; and F is used to indicate a future sum. To determine the future value of $10 invested at 6% for one year, we would need to apply the following formula: $10 × (1 + 0.06 ) = $10.60 which can be written symbolically as: F = P × (1 + i ) where: i is the interest rate F is the future worth value P is the present sum of money For n periods, the formula would be: n F = P × (1 + i )
(2.1)
The term (1 + i)n is called the single payment compound amount factor (F/P) which is used to determine the future (F) worth value of a present (P) sum of money. The reciprocal or 1/(1 + i)n is called the single payment present worth factor (P/F) which is used to determine the present (P) worth of a future (F) sum of money: P =F×
1
(1 + i )n
(2.2)
In solving economic analysis problems, you can use either a calculator and the formulas for each factor or a shorthand notation and the interest tables in Appendix C. In this text, we will set up the example problems both ways, but use the shorthand notation for problem solution. The shorthand notation for the single payment compound amount factor is written as (F/P, i, n) which means find a future sum, given a present value, at i interest, for n time periods. The interest rate identifies which page in Appendix C to look at for the value, for instance 2% interest rate; F/P identifies which column on that page, and n indicates which row in the column to find the numerical value for the factor.
Example 2.1: How to Use Appendix C To determine the single payment compound amount factor (F/P) for ten years at an interest rate of 5%, we would need to:
Time Value of Money 7
•• •• •• ••
Look on the 5% interest rate page in Appendix C Read down the column under the heading n until you come to 10 Read across to the column under the heading F/P Read the factor value as 1.629
This means that $1,000 invested today at an effective interest rate of 5% will be worth ($1,000) (1.629) or $1,629 at the end of ten years. A similar shorthand notation for the single payment present worth factor would be (P/F, i, n). This is used to find the present worth of a given future sum, received or paid at the end of n periods, at an effective interest rate of i. Using the same 5% example discussed above, to find the present worth compound amount factor (P/F) for a sum to be paid at the end of 15 years, we would need to: •• •• •• ••
Look on the 5% interest page in Appendix C Read down the column under the heading n until you come to 15 Read across to the column under the heading P/F Read the factor value as 0.481.
This means that the present worth value of $1,000 to be paid at the end of 15 years at an interest rate of 5% is ($1,000)(0.481) or $481.
Example 2.2: Contractor Investment Plan A contractor plans to purchase a pickup truck in five years. How much should the contractor invest at 6% interest today to have the $60,000 needed to purchase the truck at the end of the five years?
Solution In this problem, the purchase price is a known future value, and the unknown is the present worth amount. Mathematically, this can be written as: P=
F
(i + i )
n
=
$60, 000
(1 + 0.06 )
5
Using our shorthand notation, it is written as:
(
P =F P
F
)
(
, i,n = ( $60,000 ) P ,6%,5 F
)
Note that the unknown is always the numerator in the shorthand notation (P/F), and the known is the denominator. Looking on the page in Appendix C that contains the factors for an interest rate of 6%, the factor value is determined to be 0.747. Solving the equation yields the following answer: P = ( $60,000 )( 0.747 ) = $44,820
8 Time Value of Money
Example 2.3: Contractor Ownership Budget A contractor is considering the purchase of a new pump that will be used to remove storm runoff from open excavations. The pump will cost $15,000 and have an expected life of ten years. After ten years of use, the contractor estimates the pump salvage value will be $4,000. What is the contractor’s total cost (on a present worth basis) of owning the pump, if the effective interest rate is 8%?
Solution In this problem, the purchase price is a known present worth cost and the salvage value is a future receipt. To determine the present worth of the total cost, we subtract the present worth of the salvage value from the initial cost. Mathematically, this is written as: P = $15,000 −
$4,000
(i + 0.08 )
10
Using our shorthand notation, it is written as:
(
P = $15,000 − ( $4,000 ) P ,8%,10 F
)
Inserting the factor value from the page in Appendix C that contains the factors for an interest rate of 8% yields the following: P = $15,000 − ( $4,000 )( 0.463 ) = $15,000 − $1,852 = $13,148
Uniform Series of Payments In some situations, it is desirable to determine the single payment – present or future worth – of a uniform series of payments or receipts. In other situations, it is necessary to determine a series of equal payments or receipts. To accomplish these analyses, we will introduce A, which is defined as a series of equal payments or receipts that occur at the end of each period for n periods. It is important that you learn this definition and understand that A is not used for payments or receipts made or received at the beginning of each time period. This is known as the year-end convention. The uniform series compound amount factor (F/A) is used to determine the future worth of a series of equal payments or receipts. Mathematically, this can be written as: (1+ i )n − 1 F = A i whereas its shorthand notation is:
( F A , i, n )
(2.3)
Time Value of Money 9
The uniform series present worth factor (P/A) is used to determine the present worth of a series of equal payments or receipts. Mathematically, this can be written as: (1 + i )n − 1 P = n A i (1 + i )
(2.4)
whereas its shorthand notation is:
( P A , i, n ) The uniform series sinking fund factor (A/F) is used to determine a series of equal payments or receipts that is equivalent to a stated or required future sum. Mathematically, this can be written as: A
F
=
i (1 + i )n − 1
(2.5)
whereas its shorthand notation is:
( A F , i, n ) The uniform series capital recovery factor (A/P) is used to determine a series of equal payments or receipts that is equivalent to a given present worth sum. Mathematically, this can be written as:
A
i (1 + i )n = n P 1 + i ) − 1 (
(2.6)
whereas its shorthand notation is:
( A P , i, n ) Example 2.4: Contractor Saving Plan A contractor is investing $20,000 per year in savings certificates at an interest rate of 6% and plans to continue the investment program for six years. He is doing this so he will have a down payment for some new construction equipment. What will the value of the contractor’s investment be at the end of six years?
Solution In this problem, the annual investment is an annual uniform series, and the unknown is the future worth. Mathematically, we can use Equation 2.3 as follows:
10 Time Value of Money
6 n A × (1+ i ) − 1 ( $20,000 ) × (1+ 0.06 ) − 1 F= = 0.06 i Using our shorthand notation, it is written as:
(
F = ( $20,000 ) F
A
,6%,6
)
Inserting the factor value from the page in Appendix C that contains factors for an interest rate of 6% yields the following: F = ( $20,000 )( 6.975 ) = $139,500
Example 2.5: Contractor’s Annual Cost of Ownership A contractor purchased a new truck for $125,000 and plans to use the truck for six years. After six years of use, the estimated salvage value for the truck will be $30,000. What is the contractor’s annual cost (annual uniform series) for the truck at an interest rate of 10%?
Solution In this problem, the purchase price is given as a present value and the salvage value as a future value. The unknown is a series of equal annual payments. Mathematically, we can use Equations 2.5 and 2.6 as follows: 0.1(1 + 0.1)6 0.1 − $30,000 A = ( $125,000 ) ( ) 6 (1 + 0.1) − 1 (1 + 0.1)6 − 1 Using our shorthand notation, this is written as:
(
)
(
A = ( $125,000 ) A ,10%,6 − ( $30,000 ) A ,10%,6 P F
)
Inserting the factor values from the page in Appendix C that contains factors for an interest rate of 10% yields the following: A = ( $125,000 )( 0.230 ) − ( $30,000 )( 0.130 ) = $28,750 − $3,900 = $24,8500
Cash Flow Diagrams Cash flow diagrams are used to analyze economic alternatives. Although they are not always necessary in simple problems, these diagrams allow you to better visualize each of the individual sums and uniform series involved in the alternative.
Time Value of Money 11
The following conventions are used to standardize cash flow diagrams: ••
•• •• ••
The horizontal (time) axis is marked off in equal increments, one per interest period, up to the end of the time period under consideration (period of ownership). The interest period may be years, months, days, or any other equal time period. Receipts are represented by arrows directed up and payments are represented by arrows pointed down. Two or more receipts or payments in the same period are placed end-to-end, and these may be combined. All cash that flows during an interest period is considered to flow at the end of the period. This is known as the year-end convention. These conventions are illustrated in the following example.
Example 2.6: Dozer Cash Flow Diagram A contractor purchased a small used dozer for $20,000 that she intends to use for landscaping around newly constructed houses. Maintenance costs for the dozer are estimated to be $1,000 per year. The contractor plans to dispose of the dozer after five years and realize a salvage value of $7,000. Annual income generated by the dozer is estimated to be $5,000 per year. Draw the cash flow diagram.
Solution Arrows representing the initial purchase price and the annual maintenance costs will be drawn down in accordance with our convention, since they are payments. The salvage value and the income will be represented by arrows pointing up, because they are receipts. The resulting cash flow diagram is shown in Figure 2.1.
FIGURE 2.1
Cash Flow Diagram
12 Time Value of Money
Alternative Analysis When two or more alternatives are capable of performing the same function, the economically superior alternative will be the one with the least present worth cost. This present worth method of alternative comparison should be restricted to evaluating alternatives with equal life spans. Alternatives that accomplish the same function but have unequal lives must be compared using the annual cost method of comparison. The annual cost method assumes that each alternative will be replaced by an identical twin at the end of its useful life (infinite renewal). The first step in comparing economic alternatives is to construct a cash flow diagram for each alternative. Then a common basis (either P, F, or A) is selected for comparing the alternatives, and an equivalent sum or uniform annual series is determined for each. Using the common basis, the alternatives are compared to select the one that is most favorable. Contractors usually are interested in earning more from their equipment investment than simply the cost of money. They often use a minimum attractive rate of return to perform cash flow analysis. The minimum attractive rate of return usually includes the cost of money (interest), taxes on the equipment, and equipment insurance costs. It is used as the effective interest rate in cash flow analysis. These concepts are illustrated in the following examples. For the remainder of this chapter, we will use only the shorthand notation in the sample problems.
Example 2.7: Purchase or Lease? A contractor is considering purchasing a used dozer for $180,000 that she could use for ten years and then sell for an estimated salvage value of $10,000. Annual maintenance and repair costs for the used dozer are estimated to be $15,000 per year. As an alternative, the contractor could lease a similar dozer for $4,000 per month. Should the contractor purchase the used dozer or lease the dozer from an equipment dealer? Annual operating costs are approximately the same for both alternatives. Use a minimum attractive rate of return of 12%.
Solution Since the rental alternative is known on an annual cost basis, we will compare the alternatives on an annual cost basis. The annual cost for the lease alternative is: A = (12 months )( $4,000 / month ) = $48,000 A cash flow diagram for the purchase alternative is shown in Figure 2.2. The annual cost can be determined using the following equation:
(
)
(
)
A = ( $180, 000 ) A ,12%,10 + $15, 000 − ( $10, 000 ) A ,12%,10 P F Substituting factor values from Appendix C yields the following:
Time Value of Money 13
FIGURE 2.2
Cash Flow Diagram
A = ( $180, 000 )( 0.177 ) + $15, 000 − ( $10, 000 )( 0.057 ) A = $31, 860 + $15, 000 − 570 = $46, 290
( Lease ) $48, 000