TW15.120 2 3 4 5 WORKING PLATFORMS - Temp …

1 TWf2016: 01_DRAFT Page 1 of 134 1 2 3 4 5 working platforms 6 De sign of gra nular WORKING pla tform s for c onstruc tion pla nt 7 A guide to good prac tice 8 9 10 11 12 13 14 Publication 15 16 Published by Temporary Works Forum c/o Institution of Civil Engineers, 1 Great George 17 Street, London, SW1P 3AA, England. 18 19 First Published TBC 20 21 available as a free download from 22 23 NOTE: If you need to print this document, be aware that the pages are prepared with alternate (even) pages offset for your duplex 24 (double sided) pri nting. 25 26 TWf2016: 01_DRAFT Page 2 of 134 DOCUMENT FOR DISCUSSION 1 NOTES FOR REVIEWERS 2 3 SUMMARY 4 The document brings together existing advice and provides an overview of the current 5 state of knowledge. 6 The document includes a method for analytical design that will meet EC7 requirements 7 but it is believed that this can be improved with further research and/or better calibration 8 of partial factors.

2 9 Current national codes do not cover all ground conditions for reinforced PLATFORMS . 10 Current methods in BR470 and SP123 do not cover all ground conditions and do not 11 comply with EC7. 12 Current methods contained within BR470 and SP123 do not consider all the resistances 13 available and are, therefore, likely to be conservative. 14 There is a substantial body of relevant technical guidance and information available but 15 the precise mechanics of WORKING PLATFORMS remain somewhat unclear. 16 There are significant gaps in knowledge that may need f urther research including paper 17 study, numerical analysis, laboratory analysis and large scale testing. Particular areas 18 for research may include: 19 o Use of in-situ testing of PLATFORMS 20 o Angle of load spreading, bbbb 21 o Angle of punching shear, dddd 22 o Friction between load and platform 23 o Dynamic and cyclic effects 24 o Calibration of partial factors 25 o Application of direct assessment for soil parameters and actions 26 27 SPECIFIC QUESTIONS 28 What software, if any, is currently used by TWf Members for platform design (or 29 permanent foundation design)?

3 30 o Any comments on use? 31 o Any that they would recommend? 32 o Any not already on the list? 33 TWf2016: 01_DRAFT Page 3 of 134 Does anyone know if there is any engineering justification for using a sliding scale 1 between very soft/weak soil parameters and soft/weak soil parameters ( the 2 factor used to allow for punching mode of failure)? 3 Can anyone provide any further advice, based on their own experience, on building haul 4 roads, hard standings or WORKING PLATFORMS on or over very soft/weak ground and or 5 saturated ground? 6 Are there any photographs that members can share that would add to the sketches? 7 Would IGS Members provide information to be inserted into the table at Appendix G? 8 Suggested limits on settlement have been included based on a general knowledge of 9 what might be acceptable for mobile plant.

4 Are these too high, too low or are they ok? 10 Appendix Z Tips & Techniques is intended to provide a crib sheet of usef ul information 11 and rules of thumb , cu= Are there any suggestions on what (if anything) 12 should be included? 13 Does the document need any additional sketches? (Please draw and send in.) 14 Does the document need any other examples of construction drawings? 15 Do we need any further worked examples? 16 17 FOR INFORMATION 18 No hyperlinks have been included at this stage. 19 Blue highlighting indicates items to be confirmed. 20 Current sketches may be re-drawn for the final document. 21 Permission to use certain figures will be formally sought before final publication. 22 Two example calculations currently included are based on the BR470 examples to allow 23 a direct comparison (Further examples will be added for the final issue.)

5 24 25 Mark Davies 26 Chairman, 30th October 2015 27 28 29 TWf2016: 01_DRAFT Page 4 of 134 Members of the WORKING Party 1 2 Chairman Mark Davies RNP Associates/Barhale 3 Secretary John Carpenter Temporary Works forum (to Sept 2014) 4 David Thomas Temporary Works forum (from Sept 2014) 5 Members Steve Hall Costain 6 Mike Dyer Hochtief (UK) Construction Ltd 7 Paul Markham RNP Associates 8 Rob Moulds BAM Nuttall 9 Stuart Marchand Wentworth House Partnership 10 Richard Hare-Winton BAM Construct UK Ltd 11 Corresponding Members Grant Tolley Balfour Beatty Major Civil Engineering 12 David Baker Balfour Beatty Major Civil Engineering 13 Alan Miles Sir Robert McAlpine Ltd 14 Tim Lohmann Swanton Engineering 15 John Hodgins Galliford Try 16 Yeuyang Zhau Wentworth House Partnership 17 Nicola Hale RNP Associates 18 Andrew McNamara City University, London 19 David Corke DC Project Solutions 20 21 Interested Parties 22 23 International Geosynthetics Society Yuli Rigby, Patricia Escobar, Gary Fowmes Federation of Piling Specialists Keith Miller, Bob Handley Construction Plant-hire Association Tim Watson Health & Safety Executive Andrew Rattray.

6 John Underwood Environment Agency Steve Wittam Building Research Establishment Ken Watts, Andrew Charles Construction Industry Research and Information Association Alan Gilbertson Highways Agency Neil Loudon Network Rail Jason Johnston London Underground Martin Roach National Federation of Demolition Contractors Howard Button 24 TWf2016: 01_DRAFT Page 5 of 134 Disclaimer 1 2 This TWf Guide is not a design code, but is intended to be used in conjunction with the current 3 British Standards and other referenced documents as a guide to good practice. It is in no way 4 intended to preclude the use of other codes and methods of design or the application of 5 alternative solutions. Designers are expected to use their own engineering judgement to 6 determine the best solution and appropriate methods for design. 7 8 Although the Temporary Works Forum (TWf) does its best to ensure that any advice, 9 recommendations or information it may give either in this publication or elsewhere is accurate, 10 no liability or responsibility of any kind (including liability for negligence) howsoever and from 11 whatsoever cause arising, is accepted in this respect by the Forum, its servants or agents.

7 12 13 Readers should note that the documents referenced in this TWf Guide are subject to revision 14 from time to time and should therefore ensure that they are in possession of the latest version. 15 16 17 TWf2016: 01_DRAFT Page 6 of 134 Contents 1 2 NOTE: To navigate to pages, use CTRL + CLICK; to return to Contents use hyperli nks at the end of each section. 3 4 Foreword .. 11 5 1. General Matters .. 13 6 7 Definitions ..14 8 Legislation ..14 9 Responsibilities ..15 10 Temporary Works Co-ordinator ..15 11 Temporary Works Designer ..16 12 Reliability ..17 13 14 Occupational Health and Safety ..19 15 Environment and 16 2. Current Methods, Guidance and Standards .. 22 17 Background ..22 18 Bearing capacity method (shallow spread foundations)..23 19 TRRL LR1132 The structural design of bituminous roads (1984).

8 24 20 CIRIA SP123 Soil reinforcement with geotextiles (1996) ..25 21 BRE BR470 WORKING PLATFORMS for tracked plant (2004)..27 22 BS EN 1997 Geotechnical design (2004/2007) ..29 23 BS 8004:2015 Foundations ..30 24 BS 8006-1:2010 Strengthened/reinforced soils and other fills ..31 25 Alternative 26 Plate Loading Tests ..31 27 Geosynthetic Manufacturers Design Methods ..32 28 Commercially available software ..33 29 TWf2016: 01_DRAFT Page 7 of 134 Further Reading ..34 1 General Guidance ..35 2 ICE, Temporary Works: Principles of design and construction ..35 3 CIRIA, C703 Stability of cranes on site ..35 4 Freight Transport Association, Designing for deliveries ..35 5 Highways Agency, Design Manual for Roads and Bridges ..35 6 Highways Agency, Specification for Highway Works ..36 7 Network Rail, NR/L3/INI/CP0063 Piling adjacent to the running line.

9 36 8 Construction Plant-hire Association, Ground Conditions for Plant ..36 9 Research 10 Meyerhof / Hanna (1974, 1978, 1980, 1981) ..36 11 Houlsby / Milligan / Jewell / Burd (1989) ..37 12 Burd / Frydman (1997) ..37 13 3. Overall Design .. 38 14 Design brief ..38 15 Design life ..39 16 Design check category ..39 17 Design information ..39 18 Site/ground information ..39 19 Available ground information ..40 20 Additional ground investigation ..40 21 Scope of ground investigation ..42 22 Soil 23 Scope of plant/vehicle movements/loads ..43 24 Load data for individual plant and vehicles ..43 25 Granular fill ..44 26 Geosynthetics ..47 27 28 platform 29 Spacing of geosynthetic reinforcement ..49 30 Geometry ..49 31 Plan layout ..49 32 Vertical alignment ..50 33 TWf2016: 01_DRAFT Page 8 of 134 Edge Details.

10 50 1 Edge distances ..50 2 Edge restraint ..52 3 Durability ..53 4 Drainage ..54 5 Production Information ..55 6 Drawings ..55 7 Specifications ..55 8 Inspection and testing ..56 9 Health and safety / environmental information ..57 10 Maintenance and repair ..57 11 4. Analytical Design .. 59 12 Introduction ..59 13 platform and Foundation Mechanics ..61 14 The granular 15 The sub-formation ..63 16 General shear failure ..64 17 Local shear failure ..64 18 Punching shear failure ..65 19 Depth of influence ..65 20 General bearing capacity ..67 21 Multiple soil layers ..68 22 Effect of groundwater ..69 23 Immediate 24 Functional Requirements ..72 25 platform 26 Formation bearing capacity ..72 27 Deformation / settlements ..72 28 Actions ..74 29 Load cases ..74 30 Imposed 31 Plant weight.