DEVELOPMENT AND FIELD TESTING
OF MULTIPLE DEPLOYMENT MODEL PILE

FHWA-RD-99-194

FOREWORD

An Instrumented Multiple deployment Model Pile (MDMP) was developed for monitoring pile/soil interaction including pile capacity gain with time. The MDMP instrumentation and field installation allows to accurately obtain parameters applicable to full scale pile design. The MDMP was successfully deployed in Newbury, MA. The obtained results demonstrate the ability to predict the time-dependent behavior of full scale piles and hence to improve the design and construction of driven piles.

This report will be of interest to geotechnical researchers and practitioners dealing with structures involving driven piles.

T. Paul Teng, P.E.
Director, Office of Infrastructure
Research and Development

NOTICE

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for its contents or use thereof. This report does not constitute a standard, specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trade or manufacturers's names appear herein only because they are considered essential to the object of this document.

1. Report No. FHWA-RD-99-194	2. Government Accession No.			3. Recipient's Catalog No.
4. Title and Subtitle Development and Field Testing of Multiple Deployment Model Pile (MDMP)				5. Report Date June 2000
				6. Performing Organization Code
7. Author(s) Samuel G. Paikowsky and Leo J. Hart				8. Performing Organization Report No.
9. Performing Organization Name and Address Pruitt Energy Sources, Inc. 4307 Jefferson St., Suite 101 Hyattsville, MD 20781 UMASS-Lowell Geotechnical Engr. Research Laboratory 1 University Avenue Lowell, MA 01854				10. Work Unit No. (TRAIS)
				11. Contract or Grant No. DTFH61-95-Z-0081
12. Sponsoring Agency Name and Address Office of Infrastructure Research and Development 6300 Georgetown Pike McLean, VA 22101-2296 Massachussetts Highway Department 10 Park Plaza, Suite 3510 Boston, MA 02116				13. Type of Report and Period Covered Final Report May 1995 - March 1998
				14. Sponsoring Agency Code
15. Supplementary Notes Contracting Officer's Technical Representative (COTR) - Carl Ealy, HRDI-08 Technical Consultant: Jerry DiMaggio, HIBT-20
16. Abstract A model pile is a calibrated tool equipped with instrumentation capable of monitoring the pile/soil interaction over the pile history. Monitoring includes the installation, pore pressure dissipation combined with consolidation and soil pressure equalization, and ultimately the pile behavior under loading and failure. The model pile installation and soil-structure interaction simulate the actual field conditions of full-scale piles. As such, the obtained information can be utilized directly (e.g., skin friction) or extrapolated (e.g., pore pressure dissipation time) to predict the soil's response during full-scale pile installation. The Multiple Deployment Model Pile (MDMP) was developed as an in situ tool for site investigations. The MDMP instrumentation is capable of monitoring the pile/soil interaction throughout the life cycle of a driven pile: (1) dynamic force and acceleration readings at the pile top and along the pile during driving; (2) pore water pressure and radial stresses during equalization; and (3) skin friction, end-bearing resistance, and local (subsurface) displacement during static loading. These measurements allow the observation of pile capacity gain (a.k.a. "set-up" or "freeze") and accurately monitor the load-transfer relations. The MDMP was successfully deployed twice in Newbury, MA during March 1996. The obtained dynamic measurements allowed the evaluation of the pile's static capacity and clarified the difficulties associated with dynamic analysis of small-scale penetration. Pile capacity gain with time was examined based on normalization procedures developed by Paikowsky et al. (1995). The excess pore water pressure dissipation, variation in radial effective stresses, and pile capacity gain with time were determined for the two tests. The obtained results show that the MDMP is capable of providing accurate soil-structure interaction relations during static load testing. The measurements indicate a complex mechanism governing capacity gain that combines pore pressure dissipation and radial stress redistribution over time. These findings are used to predict the time-dependent behavior of full-scale instrumented piles and to re-evaluate the capacity gain phenomenon. The obtained results explain some unanswered questions and allow the development of procedures incorporating pile capacity gain in design and construction.
17. Key Words Model Pile, Load Test, In Situ, Capacity Gain, Set-Up, Dynamic Measurements.			18. Distribution Statement No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161
19. Security Classif. (of this report) Unclassified		20. Security Classif. (of this page) Unclassified			21. No. of Pages 284	22. Price

DEVELOPMENT AND FIELD TESTING OF MULTIPLE DEPLOYMENT MODEL PILE

FOREWORD

Technical Report Documentation Page

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

DEVELOPMENT AND FIELD TESTING
OF MULTIPLE DEPLOYMENT MODEL PILE