COMPACTION GROUTING CONSENSUS GUIDE

1 COMPACTION GROUTING CONSENSUS GUIDE COMPACTION GROUTING CONSENSUS GUIDE Committee of the Geo-Institute of the ASCE Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT ABSTRACT COMPACTION GROUTING is a viable technique for densifying loose fills and native soils that permit adequate fluid pressure dissipation. The process involves injecting a stiff mortar-like grout into the ground to displace and compact the surrounding soil. During injection, the grout displaces the soil and forces the soil grains into tighter packing, expelling air and/or water out of the effected area, and reducing pore volume. At the end of injection the ground should contain stiff grout masses and densified soil.

2 This GUIDE is specifically focused on applications of COMPACTION GROUTING where densification of the soil surrounding the grout mass is a primary objective of the ground improvement. This document is intended as a practical GUIDE for those interested in specifying, designing, and/or undertaking COMPACTION GROUTING . Field aspects of COMPACTION GROUTING are discussed, including COMPACTION GROUTING equipment, grout mix design , site investigation, and verification. The analysis and design sections of the GUIDE encompass a range of complexity from very simple through to more rigorous approaches suitable for very sensitive situations. An example specification is provided and typical applications of COMPACTION GROUTING are presented at the end of the GUIDE .

3 I Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT COPYRIGHT To be provided by the ASCE s staff ii Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT FOREWORD The Board of Direction approved revisions to the ASCE Rules for Standards Committees to govern the writing and maintenance of standards developed by ASCE. All such standards are developed by a CONSENSUS standards process managed by the ASCE Codes and Standards Committee (CSC). The CONSENSUS process includes balloting by a balanced standards committee, and reviewing during a public comment period. All standards are updated or reaffirmed by the same process at intervals between five to ten years.

4 The provisions of this document are written in permissive language and, as such, offer to the user a series of options or instructions, but do not prescribe a specific course of action. Significant judgment is left to the user of this document. This, the first edition of the COMPACTION GROUTING CONSENSUS GUIDE , has been written to promote good practice in COMPACTION GROUTING . The authors of this GUIDE believe that COMPACTION GROUTING is a reliable methodology for improving the density and strength of the soil. Similar to other GROUTING technologies, COMPACTION GROUTING is a technology based on sound engineering principles, not a black magic that can only be understood by a chosen few. And, like all other soil improvement techniques, COMPACTION GROUTING needs to be applied competently.

5 This GUIDE provides background for those interested in specifying, designing, and/or undertaking COMPACTION GROUTING . As stated above, this GUIDE is not a manual and is not intended for use as a code of practice; hence it is not accidental that non-mandatory language is used throughout the text. But those involved in the development of this GUIDE hope that it will become a useful reference for all those interested in COMPACTION GROUTING . This standard has been prepared in accordance with recognized engineering principles and should not be used without the user's competent knowledge for a given application. The publication of this standard by ASCE is not intended to warrant that the information contained therein is suitable for any general or specific use, and ASCE takes no position respecting the validity of patent rights.

6 The user is advised that the determination of patent rights or risk of infringement is entirely their own responsibility. iii Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT COMPACTION GROUTING COMMITTEE ROSTER To be finalized at the time of approval by the Codes & Standards Committee. Dawn Shuttle Chair Richard Berry Member Michael Byle Member Allen Cadden Member Jerry Di Maggio Member Eric Drooff Member Jeffrey Geraci Member Lawrence B. Gruner Member Michael G. Jefferies Member Lawrence F. Johnsen Member Curtis M. Fitzgerald Member Michael J. Miluski Member Silas Nichols Member Cumaraswamy Vipulanandan Member James Warner Member Peter T. Yen Member Carol Bowers Geo-Institute Maggie Mairena ASCE Codes & Standards Phillip Mariscal ASCE Codes & Standards iv Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT TABLE OF CONTENTS Page 1.

7 INTRODUCTION TO THE COMPACTION GROUTING GUIDE 1 What is COMPACTION GROUTING ? 1 Short history of COMPACTION GROUTING 1 Purpose and development of this GUIDE 3 References 4 2. MECHANICS OF COMPACTION GROUTING 5 Basic mechanics 5 Soil conditions 7 Field evidence on COMPACTION grout behavior 8 References 10 3. COMPACTION GROUTING MATERIALS 11 Introduction 11 Factors affecting grout mobility 12 Composition 12 design of the grout mix 13 References 15 4. GROUTING IN THE FIELD 17 Methodology 17 Equipment 20 Mixing 20 Pumps 21 Hoses and fittings 21 Safety on site 22 Casing 23 Header 25 Fittings 25 Pressure gauges 26 Drilling 26 5.

8 SUBSURFACE INVESTIGATION FOR COMPACTION GROUTING 28 Investigation planning 29 General investigations 29 Data review 29 Sampling 30 Investigation limits 30 Laboratory testing 31 Analysis and report 31 Investigations for GROUTING design 32 Defining the purpose of GROUTING 32 Defining the mechanism of GROUTING 32 Determine the extent of GROUTING 34 v Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT Select exploration methods 34 Logging of field investigation 35 Field inspectors 36 Flexibility to accommodate the unexpected 36 Record and report everything 36 References 37 6.

9 design OF COMPACTION GROUTING 38 Introduction 38 Geometric idealization of the grout mass 39 Suitability of in situ soil for COMPACTION GROUTING 38 Pressure-volume behavior of in situ soil 40 Pressure-volume behavior of grout 43 Pressure losses in the casing 44 Injection sequence 45 Injection spacing 46 Estimating grout quantities 46 Densification 47 Limitations on grout injection 48 Soil confinement 48 Influence on structures 50 Measuring refusal 51 GROUTING records 51 References 51 7. ANALYSIS OF COMPACTION GROUTING 54 Introduction 54 Methods of analysis 54 Geometric idealization 54 Alternative soil models 55 Importance of large strain 58 Simple approach 59 Numerical cavity expansion 60 Commercial finite element codes 62 Consolidation of the in situ soil during and after GROUTING 62 Importance of monitoring grout injection 64 Centrifuge modeling 64 Field trials 65 References 65 8.

10 VERIFICATION OF GROUTING EFFECTIVENESS 68 Overview of verification program development 68 Planning an effective program 69 Goals of verification 69 Verification by design 70 Test or pre-construction GROUTING 70 Monitoring during construction 70 vi Copyright of the COMPACTION GROUTING GUIDE Committee of the Geo-Institute of the ASCE 20077 August 2007 DRAFT Verification methods 72 Detecting movement 72 Crack monitors 72 Tiltmeters 73 String lines, plumb bobs, and spirit levels 74 Fluid levels 75 Rotating laser levels 76 Evaluating density changes 76 Penetration resistance 78 Excavation/coring 79 Geophysical methods 79 Summary and conclusions 80 References 80 9.