RESEARCH REPORT 463 - HSE: Information about …

1 HSE health & safety executive Avoiding structural collapses in refurbishment A decision support system Prepared by Loughborough University for the health and safety executive 2006 RESEARCH REPORT 463 HSE health & safety executive Avoiding structural collapses in refurbishment A decision support system Professor Chimay Anumba Professor Charles Egbu Mukesh Kashyap Loughborough University Loughborough Leicestershire LE11 3TU This REPORT is based on the RESEARCH project Avoiding Structural Collapse in Refurbishment: Decision Support System funded by The health and safety executive .

2 It documents the development of a Decision Support System to prevent structural collapses on refurbishment projects. The aim of the project, which commenced in April 2003, was to investigate the management of refurbishment projects and to identify areas where decision support can help in avoiding structural collapses. It builds on the recommendations made in an earlier HSE-funded RESEARCH project (HSE RESEARCH REPORT 204, 2004) on health and safety in Refurbishment Involving Structural Instability and Partial Demolition , which focused on identifying the key factors responsible for the high rate of accidents and safety incidents in refurbishment projects.

3 This REPORT and the work it describes were funded by the health and safety executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy. HSE BOOKS Crown copyright 2006 First published 2006 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the prior written permission of the copyright owner.

4 Applications for reproduction should be made in writing to: Licensing Division, Her Majesty's Stationery Office, St Clements House, 2-16 Colegate, Norwich NR3 1BQ or by e-mail to ii TABLE OF CONTENTS TABLE OF LIST OF FIGURES AND TABLES .. VI LIST OF VIII ACKNOWLEDGEMENTS .. IX executive SUMMARY .. 1 CHAPTER 1 .. 3 INTRODUCTION AND BACKGROUND TO THE 3 GENERAL INTRODUCTION .. 3 RESEARCH AIM AND 6 RESEARCH 7 STRUCTURE OF THE 8 CHAPTER 2 .. 9 KEY ISSUES IN STRUCTURAL REFURBISHMENT .. 9 INTRODUCTION .. 9 KEY PROBLEMS IN STRUCTURAL 9 CAUSES OF STRUCTURAL 10 CASE 13 Case study 1 : Catastrophic collapse of a three storey building.

5 13 Case study 2 : Collapse of masonry Case study 3 : Collapse of a concrete floor ..15 AVOIDING STRUCTURAL COLLAPSE IN REFURBISHMENT- KEY CONSIDERATIONS. 17 Evaluation of the existing structure ..18 III Reducing potential risks during Controlling demolition and unplanned collapses ..21 Appointment of a competent Measures to avoid collapse during refurbishments ..22 Compliance with statutory and regulatory Decision making process ..26 THE NEED FOR A DECISION SUPPORT SYSTEM .. 28 CHAPTER 3 .. 30 REFURBISHMENT PROCESS MODEL (RPM).

6 30 INTRODUCTION .. 30 RATIONALE FOR REFURBISHMENT PROCESS 30 DEVELOPMENT OF THE REFURBISHMENT PROCESS MODEL .. 31 EVALUATION OF THE REFURBISHMENT PROCESS 40 Objectives of the The Approach Analysis of the evaluation results of the process CHAPTER 4 .. 46 THE DECISION SUPPORT SYSTEM (DSS) .. 46 INTRODUCTION .. 46 OBJECTIVES OF THE SYSTEM 46 END-USER 47 SYSTEM ARCHITECTURE .. 54 SYSTEM DEVELOPMENT AND OPERATION .. 56 EVALUATION OF THE DECISION SUPPORT SYSTEM .. 67 Objectives of the IV The Adopted Evaluation Approach.

7 68 Analysis of the evaluation results on the SUMMARY .. 73 CHAPTER 5 .. 74 CONCLUSIONS AND 74 74 74 RECOMMENDATIONS FOR FURTHER WORK .. 75 SUMMARY .. 76 77 BIBLIOGRAPHY .. 82 APPENDIX A1 .. 84 EVALUATION QUESTIONNAIRE FOR REFURBISHMENT PROCESS MODEL (RPM) .. 84 APPENDIX A2 .. 87 EVALUATION QUESTIONNAIRE FOR DECISION SUPPORT SYSTEM (DSS).. 87 APPENDIX A3 .. 90 LIST OF CHECKLIST QUESTIONS FROM THE DSS .. 90 V 4 LIST OF FIGURES AND TABLES FIGURES PAGE No. Figure Construction worker fatalities by site activities Figure Decision making process 26 33 34 35 36 37 38 39 42 47 54 55 57 58 59 59 60 61 61 63 63 64 64 65 65 66 66 67 69 Figure Refurbishment process model Figure Pre-project phase Figure Pre-refurbishment phase -conceptual design stage Figure Pre-refurbishment phase -procurement stage Figure Refurbishment phase -partial demolition / structural alteration stage Figure Refurbishment Phase-actual refurbishment & handover stage Figure Post-refurbishment phase Figure

8 Classification of participants by role at third workshop Figure End-users of the decision support system Figure Generic architecture of decision support system Figure Interaction flow for the DSS Figure DSS flow diagram Figure Decision support system start screen Figure The DSS welcome screen Figure The log in screen Figure Initial DSS screen Figure How to start with DSS Figure The checklist screen during feasibility plan stage Figure More Information alert box Figure Screen shot showing external link Figure The checklist screen during demolition stage Figure Back-end database Figure Relationships between database tables Figure The Back-end database phase table Figure The Back-end database zone table Figure The Back end database functional table Figure Backend database user table Figure Classification of participants by role at third workshop VI TABLES Page No Occurrences of structural collapses during construction in UK 5 Table Activities and sub activities and potential decisions-making areas during refurbishment 27

9 Table Number of participants at the workshops 42 Table Summary of responses to evaluation questions 43 Table Number of participants at the workshops 68 Table Summary of responses to evaluation questions 71 VII LIST OF ABBREVIATIONS ACoP Approved Code of Practice BRE British RESEARCH Establishment CDM Construction (Design) and Management) Regulations 1994 CIRIA Construction Industry RESEARCH and Information Association DBMS Database Management System DETR Department for Environment, Transport and the Regions DRA Design Risk Assessment DS Decision Support DSS Decision Support System H&S health and safety HS&W health .

10 safety and Welfare HSE health and safety executive MS Method Statement O&M Operation and Maintenance ODPM Office of the Deputy Prime Minister PM Project Manager PS Planning Supervisor RBDM Risk-Based Decision Making RPM Refurbishment Process Model SCOSS Standing Committee on Structural safety SME Small to Medium Enterprise SMS safety Management System VIII ACKNOWLEDGEMENTS The RESEARCH team is grateful to Mr Philip G. Wright, ( health and safety executive ) for his guidance and involvement in the RESEARCH , particularly in steering the RESEARCH and providing useful Information .