SCHOOL OF CIVIL ENGINEERING JOINT HIGHWAY RESEARCH PROJECT FHWA/IN/JHRP-87/l - ( Final Report PILE CAPACITY PREDICTIONS USINC STATIC AND DYNAMIC LOAD TESTIN( Ahmad Amr Darrag $ UNIVERSITY JOINT HIGHWAY RESEARCH PROJECT FHWA/IN/JHRP-87/l - | Final Report PILE CAPACITY PREDICTIONS USIN( STATIC AND DYNAMIC LOAD TESTINt Ahmad Amr Darrag FINAL REPORT PILE CAPACITY PREDICTIONS USING STATIC AND DYNAMIC LOAD TESTING by Ahmad Amr Darrag Graduate Instructor in Research Joint Highway Research Project Project No.: C-36-36P File No. : 6-14-16 Prepared for an Investigation Conducted by the Joint Highway Research Project Engineering Experiment Station Purdue University in cooperation with the Indiana Department of Highways and the U.S. Department of Transportation Federal Highway Administration The opinion, findings and conclusions expressed in this publication are those of the author and not necessarily those of the Federal Highway Administration. Purdue University West Lafayette, Indiana February 3, 1987 1 FINAL REPORT PILE CAPACITY PREDICTIONS USING STATIC AND DYNAMIC LOAD TESTING To: H. L. Michael, Director February 3 , 1 987 Joint Highway Research Project Project: C-36-36P From: C. W. Lovell, Research Engineer Joint Highway Research Project File: 6-14-16 Attached is a Final Report on the study, "Computational Package for Predicting Pile Stress and Capacity". This report is written by Ahmad Amr Darrag of our staff, who worked under my supervision . The report is a comprehensive synthesis of pile analysis and design technique in several parts: (1) static pile load tests; (2) dynamic measurements made during pile driving; and (3) resi- dual stresses induced in the pile and adjacent soil by pile driving. These chapters have already had one review by the IDOH and the division office of the FHWA. As a result of this study Mr. Darrag has made definite recommendations to the IDOH with respect to: (1) how pile load tests should be run and interpreted; (2) why the IDOH should begin making and using dynamic measurements; and (3) how residual stresses can be estimated and used in pile foundation analysis and design. Although the report is lengthy (± 300 pages), it is recom- mended that it be printed in its entirety. The report is submitted for review, comment, and acceptance in fulfillment of the referenced study. Respectfully submitted, C. W. Lovell Research Engineer cc A.G. Altschaef f R.A. Howden B.K. Partridge J.M. Bell M.K. Hunter G.T. Satterly M.E. Cantrall J. P. Isenbarger C.F. Scholer W.F. Chen J.F. McLaughlin K.C. Sinha W.L. Dolch K.M. Mellinger c.A. Venable R.L. Eskew R.D. Miles T.D. White J.D. Fr icker P.L. Owens L.E. Wood D.E. Hancher Digitized by the Internet Archive in 2011 with funding from LYRASIS members and Sloan Foundation; Indiana Department of Transportation http://www.archive.org/details/pilecapacitypredOOdarr 1 TECHNICAL REPORT STANDARD TITLE PACE 1. Report No. "2. Government Accunon No. 3. Recipient's Catalog No. FHWA/IN/JHRP-87/ 4. TitU and Subtitle 5. Report Dot* PILE CAPACITY PREDICTIONS USING STATIC AND DYNAMIC February 3, 1987 LOAD TESTING 6. Performing Organization Code 7. Author! i) 8. Performing Organization Report No. Ahmad Amr Darrag JHRP-87/1 9, Performing Organization Nam* and Address 10. Work Unit No. Joint Highway Research Project Civil Engineering Building 11. Contract or Gront No. Purdue University JPR-K24) Part II West Lafayette, Indiana 46204 13. Type of Report and Period Covered 12. Sponsoring Agency Nome ond Addree* Final Report Indiana Department of Highways State Office Building 100 Nouth Senate Avenue 14. Sponsoring Agency Code Indianapolis, Indiana 46204 IS. Supplementary Notes Prepared in cooperation with the U.S. Department of Transportation, Federal Highway Administration. Study title is "Computational Package for Predicting Pile Stress anrl fapariry" , 16. Abstract Recommendations regarding the most reliable and economical load test methods needed by highway agencies for the design and control of bridge piles are introduced. The report contains an intensive review of the state-of-the-art of the loading equipment and instrumentations for the measurement of load and deformation. A review of the state-of-the-art of dynamic measurements and their potential uses is included. Recommendations are made concerning the necessary equipment and the associated costs. The phenomenon of residual stresses due to pile driving is discussed in detail. A simple approach was developed for the prediction of such stresses to make better predictions of pile capacity and to facilitate better interpretation of load results. A computer program, named PPILENF, was developed for the purpose of predicting additional pile loads due to negative skin friction. A complete user's manual is given, including several illustrative examples. 17. Key Words 18. Distribution Stotemont Pile, static load tests, quick testing No restrictions. This document is methods, dynamic measurements, residual available to the public through the stresses, negative skin friction National Technical Information Service, Springfield, VA 22161 19. Security Closslf. (of this report) 20. Security Closslf. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 271 F».« HOT P 1700.7 fa. 69) ACKNOWLEDGEMENTS The author would like to express his sincere appreciation to his major professor, Dr. C. W. Lovell, for his invaluable gui- dance during the preparation of this report and the critical review of the manuscript. The author would also like to thank Mr. Steve Hull of the Indiana Department of Highways and Mr. Paul Hoffman of the Federal Highway Administration for their assistance as members of the Advisory Committee for the project. Thanks are extended to Mrs. Cathy Ralston and Mrs. Kathie Roth for the excellent job they did in typing the report. The financial support for this report was provided by the Indiana Department of Highways and the Federal Highway Adminis- tration. The research was administered through the Joint Highway Research Project, Purdue University, West Lafayette, Indiana. TABLE OF CONTENTS Page LIST OF TABLES Vi LIST OF FIGURES Vlii LIST OF SYMBOLS AND NOMENCLATURE xiii HIGHLIGHT SUMMARY xvi CHAPTER 1 INTRODUCTION 1 CHAPTER 2 PILE LOAD TESTS 5 2.1 Introduction 5 2.1.1 Purpose of Pile Load Tests 5 2.1.2 Planning the Test Program 2.1.3 Types of Pile Load Testing 9 2.1.4 Application of Results 9 2.2 Axial Compression Load Tests 13 2.2.1 Loading and Instrumentation 13 2.2.1.1 Loading Systems 13 2.2.1.2 Measurement of Settlement of Pile Head 22 2.2.1.3 Measurement of Pile Movements and Loads at Various Points Along the Pile 28 2.2.1.4 Residual Stresses 34 2.2.1.5 Sources of Error in Settlement Measurements 35 2.2.1.5.1 Errors Resulting from Use of Reference Beam . 35 2.2.1.5.2 Errors Resulting from Jacking Against Anchor Piles 40 2.2.1.5.3 Errors Resulting from Jacking Against Ground Anchors 42 2.2.2 Test Procedures 45 2.2.2.1 Maintained Loading Test 47 2.2.2.1.1 Procedure 47 2.2.2.1.2 Interpretation of Test Results 53 a. Ultimate Load ... 53 b. Empirical Methods of Working Loads ... 55 c. Plastic and Elastic Deformations ... 58 IV d . Distribution of Load to Soil 59 e. Settlement Behavior 61 f. Some Factors Influ- encing Interpretation of Test Results . 62 2.2.2.2 Constant Rate of Penetration Test 63 2.2.2.2.1 Procedure 64 2.2.2.2.2 Interpretation of Test Results 67 2.2.2.3 Method of Equilibrium 72 2.2.2.3.1 Procedure 73 2.2.2.3.2 Discussion and Interpre- tation of Results ... 74 2.2.2.4 Load Testing by the Texas Highway Department 77 2.2.2.4.1. Procedure 81 2.2.2.4.2. Correlation Studies by THD 85 2.3 Other Types of Pile Load Tests 94 2.3.1 Uplift Tests 94 2.3.2 Lateral Load Tests 96 2.3.2 Torsional Testing 102 2.4 Recommended Procedures for Axial Pile Load Tests . 104 2.4.1 General •. 104 2.4.2 Texas Quick Load Test Method 107 2.4.3 Method of Equilibrium 117 CHAPTER 3 DYNAMIC MEASUREMENTS FOR PILE DRIVING 120 3.1 Introduction 120 3.1.1 Pile Capacity 120 3 .1 .2 Hammer Performance 121 3.1.3 Pile Performance and Integrity 122 3.2 Technical Background on Dynamic Measurements . 123 3.2.1 Acceleration Measurement 124 3.2.2 Force Measurement „ 126 3.2.3 Recording Devices 128 3.2.4 Developments in Dynamic Measurements . 131 3.3 Estimation of the Pile Capacity Using Dynamic Measurements 134 3.3.1 Simplified Approach Using Field Computers . 135 3.3.2 Office Analysis Using CAPWAP 141 3.4 Evaluation of the Performance of Pile Driving Systems Using Dynamic Measurements 149 3.5 Evaluation of the Pile Performance Using Dynamic Measurements 155 3.6 Conclusions and Recommendations 161 CHAPTER 4 RESIDUAL STRESSES DUE TO PILE DRIVING 166 4.1 General 166 4.2 Current Methods Used for Residual Stress Measure- ment 172 4.3 Review of Research on Residual Stresses for Piles in Cohesionless Soils 176 4.4 Numerical Evaluation of Residual Stresses and Factors Affecting These Stresses 184 4.4.1 Obtaining Residual Stresses 184 4.4.2 Effect of Considering Residual Stresses in the Dynamic Analysis 188 4.4.3 Distribution of Residual Forces along Pile Shaft 196 4.4.4 Factors Affecting the Magnitude of Residual Stresses 203 4.4.4.1 Effect of the Driving System and Elements 203 4.4.4.2 Effect of Total Soil Resistance . 205 4.4.4.3 Effect of Skin Friction Percent .