01683853 PDF BRITISH STANDARD BS 8006 1995 Incorporating Amendment No 1 Code of practice for Strengthened reinforced soils and other fills ICS 93 020 BS 8006 1995 This British Standard, having been prepared under the direction of the Sector Board for Building and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 November 1995 © BSI 06 1999 The following BSI references relate to the work on this standard Committee reference B5264 Draft for.
BRITISH STANDARD Code of practice for Strengthened/ reinforced soils and other fills ICS 93.020 BS 8006:1995 Incorporating Amendment No BS 8006:1995 Committees responsible for this British Standard The preparation of this British Standard was entrusted by Technical Committee B/526, Geotechnics, to Subcommittee B/526/4, Strengthened/reinforced soils and other fills, upon which the following bodies were represented: British Coal Corporation British Railways Board British Textile Confederation County Surveyors’ Society Department of Transport (Highways Agency) Department of Transport (Transport Research Laboratory) Federation of Civil Engineering Contractors Institution of Civil Engineers Institution of Highways and Transportation Institution of Structural Engineers Zinc Development Association This British Standard, having been prepared under the direction of the Sector Board for Building and Civil Engineering, was published under the authority of the Standards Board and comes into effect on 15 November 1995 © BSI 06-1999 The following BSI references relate to the work on this standard: Committee reference B/526/4 Draft for comment 91/14831 DC ISBN 580 24216 Amendments issued since publication Amd No Date Comments 10252 March 1999 Indicated by a sideline in the margin BS 8006:1995 Contents Page Committees responsible Inside front cover Foreword vi Section General 1.1 Scope 1.2 References 1.3 Definitions 1.4 Symbols Section Concepts and fundamental principles 2.1 General 2.2 Limit state principles 2.3 Partial factors 2.4 Design loads 10 2.5 Design strengths 10 2.6 Fundamental mechanisms 11 2.7 Soil reinforcing mechanisms in walls and slopes 12 2.8 Soil reinforcing mechanisms in embankment foundations 12 2.9 Soil reinforcement interaction 13 2.10 Soil properties to be considered 14 2.11 Reinforcement geometry 15 2.12 Reinforcement bond 16 2.13 Effects of flexible reinforcement axial stiffness on loads 16 2.14 Factors affecting tensile behaviour of flexible reinforcement 17 Section Materials 3.1 Soils and fills 23 3.2 Reinforcing materials 26 3.3 Facings 28 3.4 Fasteners between the facing and reinforcing elements 30 3.5 Testing materials and components not covered by relevant specifications 30 Section Testing for design purposes 4.1 General 34 4.2 Fill and ground 35 4.3 Soil reinforcement 36 4.4 Facing units 40 4.5 Trial constructions to evaluate constructability 40 Section Principles of design 5.1 Design philosophy 41 5.2 Service life 41 5.3 Factors of safety 41 5.4 Fasteners and connections 44 5.5 Serviceability 45 5.6 Design information 45 Section Design of walls and abutments 6.1 General 53 6.2 Partial factors used in this section 53 6.3 Basis for design 55 6.4 Dimensions of the structure 56 6.5 External stability 57 6.6 Internal stability 61 © BSI 06-1999 i BS 8006:1995 6.7 Facings 6.8 Connections 6.9 Soil nailing for walls Section Design of reinforced slopes 7.1 General 7.2 Partial factors used in the design of reinforced slopes 7.3 Areas of application 7.4 Reinforcement of fill materials 7.5 Reinforcement of existing ground 7.6 Facings Section Design of embankments with reinforced soil foundations on poor ground 8.1 General 8.2 Partial factors used in the design of embankments with reinforced soil foundations on poor ground 8.3 Reinforced embankments over soft and very soft foundation soils 8.4 Reinforced embankments over areas prone to subsidence Section Construction and maintenance 9.1 General 9.2 Walls and abutments 9.3 Slopes 9.4 Foundations 9.5 Handling, storage and placing Annex A (normative) Assessment of partial material factors for reinforcements Annex B (normative) Microbial activity index test Annex C (normative) Determination of effective angle of internal friction (ẻẵ) and effective cohesion (c½) of earthworks materials Annex D (normative) Site damage test Annex E (normative) Determination of coefficient of friction and adhesion between fill and reinforcing elements or anchor elements for reinforced soil and anchored earth structures Annex F (normative) Trial constructions Annex G (informative) Propping forces Figure — Range of applications of reinforced soil Figure — Effect of reinforcement on a soil element Figure — Reinforcing mechanisms in walls and slopes Figure — Forms of reinforcement Figure — Types of seams Figure — Stitch configuration Figure — Bodkin joint Figure — Selection of materials for reinforcement, connections and facings for reinforced soil structures Figure — Stress/strain relationship for sand under plane strain loading Figure 10 — Examples of structures in category — applicable to walls and slopes Figure 11 — Examples of structures in category — applicable to walls and slopes Figure 12 — Examples of foundations in category ii Page 72 72 77 100 100 101 101 107 110 122 122 123 134 151 151 156 160 163 177 184 185 186 189 190 190 19 20 21 22 31 32 32 33 40 48 49 50 © BSI 06-1999 BS 8006:1995 Page Figure 13 — Examples of structures in category — applicable to walls and slopes Figure 14 — Examples of foundations in category Figure 15 — Definitions and types of walls and abutments Figure 16 — Common facings used with structures Figure 17 — Load combinations showing load factors Figure 18 — Design procedure for reinforced soil walls Figure 19 — Initial sizing of structures Figure 20 — Sizing of walls with various geometries Figure 21 — Definition of embedment, Dm Figure 22 — Ultimate limit states — external stability Figure 23 — Serviceability limit states — external and internal stability Figure 24 — Definition of soil properties and principal loads Figure 25 — Pressure distribution along base of wall Figure 26 — Types of slip surface failure Figure 27 — Stability — effects to be considered Figure 28 — Stresses imposed due to self weight, surcharge and retained backfill Figure 29 — Dispersal of vertical strip load through reinforced fill — tie back wedge method Figure 30 — Dispersal of horizontal shear through reinforced fill — tie back wedge method Figure 31 — Determination of adherence capacity of the reinforcement — tie back wedge method Figure 32 — Types of reinforced soil anchors Figure 33 — Internal wedge stability Figure 34 — Internal wedge stability analysis of simple problem Figure 35 — Assessment of post-construction strain under applied load Tavj Figure 36 — Variation of coefficient of earth pressure with depth — coherent gravity method Figure 37 — Dispersal of vertical strip load through reinforced fill — coherent gravity method Figure 38 — Dispersal of horizontal shear through reinforced fill — coherent gravity method Figure 39 — Line of maximum tension for retaining wall — coherent gravity method Figure 40 — Definition of maximum tension line (retaining wall without superimposed strip loads) — coherent gravity method Figure 41 — Lines of maximum tension for structures with strip loads — coherent gravity method Figure 42 — Definition of line — coherent gravity method Figure 43 — Examples of structures requiring global stability analysis — coherent gravity method Figure 44 — Soil nailed walls Figure 45 — Examples of slope reinforcement Figure 46 — Design basis for reinforced slopes Figure 47 — Ultimate limit states — external stability Figure 48 — Ultimate limit states — internal stability Figure 49 — Ultimate limit states — compound stability Figure 50 — Serviceability limit states © BSI 06-1999 51 52 79 80 81 82 83 84 85 85 86 86 87 88 88 89 89 90 90 91 92 93 94 94 95 95 96 96 97 97 98 99 111 112 112 113 113 114 iii BS 8006:1995 Page Figure 51 — Definition of soil properties and principal loads for reinforced steep fill slopes Figure 52 — Two-part wedge analysis for internal stability of reinforced fill slopes Figure 53 — Other methods of internal stability analysis of reinforced fill slopes Figure 54 — Force components in two-part wedge analysis of compound stability Figure 55 — Applications of soil nailing Figure 56 — Use of two-part wedge analysis for soil nailing Figure 57 — Use of log-spiral analysis for soil nailing Figure 58 — Reinforcement used to control initial stability only of embankment Figure 59 — Reinforcement used to control both initial stability and settlement of embankment Figure 60 — Ultimate limit states for basal reinforced embankments Figure 61 — Serviceability limit states for basal reinforced embankments Figure 62 — Procedure for assessing rotational stability by slip circle analysis Figure 63 — Lateral sliding stability at fill/reinforcement interface Figure 64 — Analysis of foundation extrustion stability Figure 65 — Ultimate limit state stability analysis for basal mattress reinforcement Figure 66 — Piled embankment configurations Figure 67 — Ultimate limit states for basal reinforced piled embankments Figure 68 — Serviceability limit states for basal reinforced piled embankments Figure 69 — Outer limit of pile caps Figure 70 — Variables used in determination of Trp Figure 71 — Lateral sliding stability at fill/reinforcement interface Figure 72 — Variables used in analysis of overall stability of basal reinforced piled embankments Figure 73 — Conceptual role of reinforcement in limiting surface deformations due to subsidence Figure 74 — Parameters used to determine reinforcement Figure 75 — Wrap-around construction techniques Figure 76 — Reinforced soil retaining walls Figure 77 — Typical drainage detail for abutment bankseat Figure 78 — Reinforced soil mass acting as drain Figure 79 — Porous pipe at wall face Figure 80 — Drainage details for walls supporting cuttings Figure 81 — Wrap-around facing Figure 82 — Reinforced gabions Figure 83 — Reinstatement of failed slope Figure 84 — Soil nailing technique Figure 85 — Laying and jointing sequence for basal reinforcement Figure 86 — Advancing mud wave Figure 87 — Inverted “U” construction Figure 88 — Construction of a “U” shaped leading edge iv 115 116 117 118 119 120 121 138 138 139 140 141 142 143 144 145 146 147 147 148 148 149 150 150 166 167 168 168 169 170 170 171 172 173 174 175 175 175 © BSI 06-1999 BS 8006:1995 Figure 89 — Basal mattress fabrication technique Figure A.1 — Assessment of fm 11 Figure A.2 — Assessment of fm 122 Figure A.3 — Assessment of fm 12 Figure A.4 — Assessment of fm 21 Figure D.1 — Schematic layout of test bays Table — Factors affecting performance Table — Selection of fill for walls and abutments Table — Category of structure depending upon ramification of failure Table — Electrochemical properties of fill used with plain steel, galvanized steel and stainless steel materials Table — Grading of fill material for basal mattresses Table — Minimum properties of some different types of steel reinforcement Table — Sacrificial thickness to be allowed on each surface exposed to corrosion Table — Jointing methods and approximate strengths of polymeric materials Table — Material standards for different types of facing Table 10 — Properties of bolts and screws up to 40 mm stock size Table 11 — Properties of dowels and rods up to 40 mm stock size Table 12 — Examples of service life Table 13 — Checklist for investigations of reinforcement products Table 14 — Factors affecting durability and performance of buried soil reinforcement materials Table 15 — Partial materials factors for reinforcements Table 16 — Summary of partial factors to be used in section Table 17 — Partial load factors for load combinations associated with walls Table 18 — Partial load factors for load combinations associated with abutments Table 19 — Dimensions of walls and abutments Table 20 — Determination of the minimum embedment as a function of the mechanical height H in metres and the factored bearing pressure qr in kN/m2 Table 21 — Minimum vertical movement capacities required for facing systems to cope with vertical internal settlement of reinforced fill Table 22 — Guide to the effects of settlement Table 23 — Usually accepted tolerances for faces of retaining walls and abutments Table 24 — Serviceability limits on post-construction internal strains for bridge abutments and retaining walls Table 25 — Connection loads for ultimate and serviceability limit states Table 26 — Summary of partial factors to be used in section Table 27 — Summary of partial factors to be used in section Table 28 — Arching coefficient Cc for basal reinforced piled embankments Table B.1 — Classification for microbial activity Table B.2 — Determination of sulfate reducing bacteria classification List of references © BSI 06-1999 Page 176 180 181 182 183 188 15 23 23 24 26 27 27 29 29 30 32 34 38 38 42 53 54 55 57 57 60 60 62 63 73 101 122 131 185 185 192 v BS 8006:1995 Foreword This British Standard has been prepared by Subcommittee B/526/4, Strengthened/reinforced soils and other fills It supersedes PD 6517:1988 which is withdrawn There has been an increasing use of soil reinforcement techniques in Great Britain over the past decade for a variety of applications from vertical walls and abutments through reinforced slopes to reinforced foundations The modern impetus for the use of such techniques stems from the development of reinforced soil techniques for vertical or near vertical slopes some 25 years ago, generally using metallic reinforcement, usually with modular concrete facing units The development of the use of polymeric materials in the form of geotextiles in the civil engineering industry has been accompanied by their introduction into reinforced soil applications including the reinforcing of slopes and foundations Reinforced soil techniques are now used extensively for a range of design lives and service requirements and are still in an active stage of development, particularly as far as the use of polymeric materials is concerned, and it was felt that the absence of a code of practice covering the techniques was hindering their wider development This code of practice contains material which is both for the information and guidance of engineers and material which forms recommendations on good practice Engineering judgement should be applied to determine when the recommendations of the code should be followed and when they should not This code of practice embodies the experience of engineers successfully engaged on the design and construction of the particular class of works It is intended for the use of engineers with some knowledge of the subject as a basis for the design of similar works A code of practice represents good practice at the time it is written and, inevitably, technical developments can render parts of it obsolescent in time It is the responsibility of engineers concerned with the design and construction of works to remain conversant with developments in good practice, which have taken place since publication of the code It has been assumed in the drafting of this British Standard that the execution of its provisions is entrusted to appropriately qualified and experienced people As a code of practice, this British Standard takes the form of guidance and recommendations It should not be quoted as if it were a specification and particular care should be taken to ensure that claims of compliance are not misleading A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application Compliance with a British Standard does not of itself confer immunity from legal obligations Summary of pages This document comprises a front cover, an inside front cover, pages i to vi, pages to 196, an inside back cover and a back cover This standard has been updated (see copyright date) and may have had amendments incorporated This will be indicated in the amendment table on the inside front cover vi © BSI 06-1999 BS 8006:1995 Section General 1.1 Scope This British Standard contains guidelines and recommendations for the application of reinforcement techniques to soils, as fill or in situ, and to other fills The standard is written in a limit state format and guidelines are provided of safety margins in terms of partial material factors and load factors for various applications and design lives The code is divided into nine sections Section identifies the scope, definitions and notation of the code Section describes the concepts and fundamental principles of reinforced soil Section provides recommendations for the use of materials where existing standards are available Where materials are used which are not covered by existing standards or where known materials are to be used in ways not covered by existing standards section gives recommendations for the testing and approval of such materials Sections to relate to design, construction and maintenance of walls and abutments, slopes and foundations They include specific recommendations for characterization of the soils to be used and other factors affecting the design and performance of the structures Emphasis is placed on quality control both with regard to the consistency of the properties of the fill and reinforcing materials and to the handling of the materials on site Much of the existing practice of reinforced soil is based on the use of limit equilibrium design methods which incorporate a global factor of safety In keeping with the principles of limit state design, consistent structural dimensions and materials quantities have been maintained with existing practice by calibration of the partial factors in the limit state design relationships in this code This approach is different to that adopted by some concurrent codes of practice, e.g BS 8002:1994, which rely on the use of “worst credible” parameters to develop an adequate margin of safety The clauses are supplemented by a substantial list of references to enable the user to consider in greater depth the applications of the technique 1.2 References 1.2.1 Normative references This British Standard incorporates, by dated or undated reference, provisions from other publications These normative references are made at the appropriate places in the text and the cited publications are listed on page 192 For dated references, only the edition cited applies; any subsequent amendments to or revisions of the cited publication apply to this British Standard only when incorporated in the reference by amendment or revision For undated references, the latest edition of the cited publication applies, together with any amendments 1.2.2 Informative references This British Standard refers to other publications that provide information or guidance Editions of these publications current at the time of issue of this standard are listed on page 193, but reference should be made to the latest editions 1.3 Definitions For the purposes of this British Standard the following definitions apply 1.3.1 anchored earth form of reinforced soil which uses anchors embedded within the soil mass to provide stability Resistance to pull-out is provided by passive action of the anchor and friction along the anchor shaft or loop 1.3.2 cohesive frictional fill fill containing at least 15 % material passing a 63 4m sieve in accordance with BS 410 NOTE It is described in the Specification for Highway Works [1] under fill material classes 7C and 7D 1.3.3 fill material material in the reinforced soil structure in contact with the reinforcing elements, connections and facings, including both selected fill and any filter material © BSI 06-1999 BS 8006:1995 1.3.4 frictional fill fill containing less than 15 % material passing a 63 4m test sieve in accordance with BS 410 NOTE It is described in the Specification for Highway Works [1] under fill material classes 6I and 6J 1.3.5 geogrid polymeric, planar structure consisting of an open network of connected tensile elements used in geotechnical and civil engineering applications 1.3.6 geotextile permeable, polymeric material, which may be woven, nonwoven or knitted, used in geotechnical and civil engineering applications 1.3.7 partial factors specific design parameters to account for uncertainty 1.3.8 polymeric reinforcement generic term that encompasses geosynthetic materials used in geotechnical engineering such as geotextiles and geogrids 1.3.9 reinforced soil general term which refers to the use of placed or in situ soil or other material in which tensile reinforcements act through interface friction, bearing or other means to improve stability 1.3.10 reinforcement base strength unfactored strength of the reinforcement at the end of its selected design life 1.3.11 reinforcement design strength factored strength of the reinforcement at the end of its selected design life It is the reinforcement base strength divided by the appropriate partial material factor 1.3.12 reinforcement 1.3.12.1 axially flexible reinforcement reinforcement that can absorb tensile loads only 1.3.12.2 axially stiff reinforcement reinforcement that can absorb tensile, shear and bending loads 1.3.12.3 extensible reinforcement reinforcement that sustains the design loads at strains greater than % 1.3.12.4 inextensible reinforcement reinforcement that sustains the design loads at strains less than or equal to % 1.3.13 retained backfill fill material located between the reinforced mass and the natural soil © BSI 06-1999 BS 8006:1995 In addition to the effects of the soil environment, the state of stress and the selected design life of the reinforcement should also be taken into account when determining fm22 For reinforcements which utilize protective layers or coatings these can be more resistant to attack than the load carrying elements being protected If the effect of installation damage is to expose the load carrying elements to the soil environment then the effects of this should be incorporated in determining fm22 Similarly the combined effects of stress, short term damage and long term exposure to the soil environment can be synergistic and therefore amplify the effects of the soil environment alone Annex B (normative) Microbial activity index test NOTE This is a subsidiary method for sulfate reducing bacterial assessment B.1 Principle The method is to test the soil for microbial activity in a nutrient rich environment Three soil samples should be taken as aseptically as possible at the borrow pit The soil is sealed in an air tight container with no air space The test is carried out within 24 h of taking the soil sample B.2 Apparatus B.2.1 Glass flask, of 1.0 l capacity B.2.2 Measuring cylinder, of 200 ml capacity B.2.3 Two beakers, of 500 ml capacity B.2.4 Glass stirring rod B.2.5 A balance, readable and accurate to 0.001 g B.2.6 pH meter B.2.7 Autoclave B.2.8 Incubator B.3 Reagents B.3.1 Potassium dihydrogen phosphate B.3.2 Ammonium chloride B.3.3 Calcium sulfate B.3.4 Magnesium sulfate B.3.5 Yeast powder B.3.6 70 % sodium lactate solution B.3.7 Ammonium ferrous sulfate, 0.25 g freshly made up in ml of water B.3.8 N/10 sodium hydroxide B.4 Procedure B.4.1 Accurately weigh the following and mix in 500 ml capacity beaker: — g potassium dihydrogen phosphate; — g ammonium chloride; — g calcuim sulfate; — g magnesium sulfate Make up to 200 ml with tap water and dissolve as much as possible by warming in the beaker B.4.2 Take 100 ml of the above solution, place in a 1.0 l flask and make up to 1.0 l with tap water B.4.3 Add to this solution g yeast powder, g 70 % sodium lactate solution and ml of 0.25 g ammonium ferrous sulfate freshly made up in ml of water Adjust the pH to 7.2 to 7.4 with N/10 sodium hydroxide B.4.4 Take the sterilized Baars medium, as produced in B.4.1 to B.4.3, and boil for 30 s B.4.5 Fill the sample bottles to the top For each soil sample add g of soil to a bottle and 0.1 g and 0.01 g to further bottles (in duplicate) B.4.6 Fill two sample bottles with Baars medium only (to act as standards) 184 © BSI 06-1999 BS 8006:1995 B.4.7 The bottles are then put into an incubator at 30 °C and the time taken for first blackening of the soils to occur is noted B.5 Classification Classification should be carried out in accordance with Table B.1 The activity index is obtained from the sum of number factor and soil factor and using Table B.2 to determine the sulfate reducing bacteria classification Table B.1 — Classification for microbial activity Number factor Growth occurs in g samples after ( )days (0–2) (2–4) (4–6) (6–8) (8–10) (above 10) Soil factor Growth occurs in 0.1 g samples after ( ) days; or (4) (6) (8) (10) (12) (above 14) Growth occurs in 0.01 g samples after ( ) days (6) (8) (10) (12) (14) (above 16) NOTE If growth occurs in 0.1 g or 0.01 g samples before growth is observed in g samples then the soil factor automatically becomes zero Table B.2 — Determination of sulfate reducing bacteria classification Activity index Less than 5 to above Classification Inactive Active Highly active Annex C (normative) Determination of effective angle of internal friction (ẻ ẻẵ) and effective cohesion (c½) of earthworks materials NOTE The effective angle of internal friction ẻẵ and effective cohesion cẵ should be determined by shear box tests The apparatus used should be commercially available shear box apparatus in accordance with BS 1377-7 C.1 Shear box tests for granular materials C.1.1 Preparation The undrained constant rate of strain shear box test should be used The plan size of the shear box should be 300 mm2 with a depth of not less than 150 mm The maximum particle size should be not greater than 0.125 of the depth of the sample in the shear box Three samples should be tested, each sample occupying the full depth of the shear box and should be compacted to 92 % ± % of the maximum dry density which should be determined in accordance with BS 1377-4 using the vibrating hammer method The samples should not be immersed in water Each of the three samples should be subjected to a different effective normal stress equal to the maximum vertical pressure in the fill at the base, quarter height and mid-height of the structure respectively Each of the samples should be sheared in a single stage test within h of compaction and the rate of shearing should be such that no pore water pressure is generated C.1.2 Procedure Obtain the peak shear stress for a particular normal stress from the measurement of the maximum shear value For each size of shear box determine a graph of the shear strength envelope Take the test results obtained using the 300 mm square box as the properties of the fill Use the initial test results obtained using the 60 mm2 box for the subsequent quality control of the fill © BSI 06-1999 185 BS 8006:1995 C.1.3 Information to be recorded The following additional information should be recorded for each test: a) normal stress applied in kN/m2; b) peak shear stress in kN/m2; c) strain at peak shear stress in % C.2 Shear box tests for cohesive materials C.2.1 Preparation The drained constant rate of strain shear box test should be used The shear boxes should be 300 mm2 in plan by not less than 150 mm deep or 60 mm2 in plan by not less than 40 mm deep The maximum particle size should be not greater than 0.125 of the depth of the sample in the shear box For the initial determination of fill properties three samples should be tested in each size of shear box The samples should occupy the full depth of the box and should be compacted to 92 % ± % of the maximum dry density which should be determined in accordance with BS 1377-4 using the 4.5 kg rammer method To allow the sample to soften the shear box assembly should then be immersed in water for a minimum period of 24 h Each of the three samples should be subjected to a different effective normal stress equal to the maximum vertical pressure in the fill at the base, quarter height and mid-height of the structure respectively Normal stresses should be applied to the softened sample for a minimum period of 24 h prior to shearing The rate of shearing should be such that no pore water pressure is generated C.2.2 Procedure Obtain the peak shear stress for a particular normal stress from the measurement of the maximum shear value For each size of shear box determine a graph of the shear strength envelope Take the test results obtained using the 300 mm2 box as the properties of the fill Use the initial test results obtained using the 60 mm2 box for the subsequent quality control of the fill C.2.3 Information to be recorded The following additional information should be recorded for each test: a) normal stress applied in kN/m2; b) peak shear stress in kN/m2; c) strain at peak shear stress in %; d) moisture content after test C.3 Shear box tests for pulverized-fuel ash material For pulverized-fuel ash material the procedure should be as for C.2 except that: a) the maximum dry density should be determined in accordance with BS 1377-4 using the 2.5 kg rammer method; b) the normal stress should be applied and the sample should be immersed as soon as the box has been filled and compacted; c) an additional sample should be subjected to an effective normal stress equal to the maximum vertical pressure in the fill at three quarters of the height of the structure or the lowest attainable normal stress whichever is greater; d) the normal stress should be applied concurrently with the immersion of the sample for a period of 24 h Shearing of the sample should then be carried out without further delay Annex D (normative) Site damage test D.1 General The following procedure for site damage test is applicable to both metallic and polymeric reinforcements However, the extent of the test may be curtailed at the discretion of the assessment authority Other test layouts, configurations and procedures may be considered to those detailed in the following clauses 186 © BSI 06-1999 BS 8006:1995 The purpose of the site damage test is: a) to place the reinforcement under a range of fills that conform to the grading limits of the Specification for Highway Works [1] and to compact those fills in accordance with and in excess of that specification; b) to recover the reinforcement and measure its tensile strength and stiffness and estimate the site damage; c) quantify any loss of strength of the reinforcement due to the construction process D.2 Test site A level site should be prepared and laid out in nine bays each 3.5 m × 3.5 m as shown in Figure D.1, leaving working space for construction plant to gain access around the test area without crossing the bays Where the reinforcement is planned to be used within a zone of compacted fill, e.g a reinforced soil retaining wall or fill slope, a 150 mm thick layer of material (or 1.5 times the maximum fill size, whichever is the greater) should be placed and compacted in each bay prior to the installation of the reinforcement This material should be the same as that to be placed in the layer above the reinforcement Where the reinforcement is planned to be used beneath a zone of compacted fill, e.g a basal reinforced embankment on soft soil, a 150 mm thick layer of the typical foundation soil (or 1.5 times the maximum fill size, whichever is the greater) should be placed in each bay prior to the installation of the reinforcement D.3 Arrangement of the reinforcement Sufficient portions of reinforcement each 10.5 m long should be prepared These should be placed across each bay as shown in Figure D.1 No tension should be applied to the reinforcement The QC roll number and/or batch number of the reinforcement should be recorded Sufficient unused reinforcement from this batch should be retained and prepared for tensile testing as control samples D.4 Fill materials Three different gradings of the fill material proposed for use should represent the coarse, middle and fine fill The fill material may be frictional fill, cohesive frictional fill or other materials as defined elsewhere in this code Each layer of material should be compacted to a thickness of 150 mm or 1.5 times the maximum particle diameter, whichever is greater Particle size distribution for each type of fill should be determined by dry sieve analysis Fill should not be end tipped onto the reinforcement but should be spread over by bulldozer D.5 Compaction plant Compaction of the fill should be carried out in accordance with the Specification for Highway Works [1] The roller mass per metre width and number of passes should be selected in accordance with 9.2.3.2 and Table 6/4 in the Specification for Highway Works [1] D.6 Compaction A maximum of three levels of compaction should be used in the trial a) Standard compaction The number of passes of the roller to compact the fill to the selected layer thickness should be in accordance with 9.2.3.2 and Table 6/4 of the Specification for Highway Works [1] b) Over-compaction Twice the number of passes as specified in a above should be used to compact the fill to the selected layer thickness c) Double layer compaction The formation of two layers of selected compacted thickness The number of passes of the roller as given in a) above to compact the first layer of fill to the selected layer thickness A second layer of fill should then be spread and compacted to the selected layer thickness by the number of passes of the roller as given in a) above NOTE A compaction trial may have to be carried out in advance of the site damage trial to determine the uncompacted fill thickness that will compact to the selected layer thickness under the three compactive efforts © BSI 06-1999 187 BS 8006:1995 Figure D.1 — Schematic layout of test bays D.7 Site testing The reinforcement should be subjected to a variety of fill materials and compactive efforts as shown in Figure D.1 188 © BSI 06-1999 BS 8006:1995 Levels should be taken on a m2 grid within each bay after completion of each layer to determine the mean layer thickness mm Variations in surface levels of the compacted fill should not exceed +20 of the true finished level as –30 mm measured on a m grid D.8 Recovery of the reinforcement After completion of the site testing the compacted fill should be manually removed from all bays Those pieces of reinforcement that are accidentally damaged by spades should not be used in subsequent tests D.9 Preparation of samples Three specimens should be prepared from each length of the reinforcement for visual assessment of site damage and tensile testing D.10 Visual assessment of site damage A visual assessment of the site damage to each sample should be made and recorded Damage should be classified into four categories a) General abrasion This describes the condition of the reinforcement when damaged by contact with many small stones which leave the surface of the reinforcement covered in small scratches and abrasions b) Splits, cuts and bruises This describes the damage caused by the action of larger particles a) A split should describe the region of a strip or rib when locally split into a number of small strands so that light passes through b) A cut should describe the rib or strip when a sharp indentation is made across or along the reinforcement c) A bruise should describe the rib or strip when flattened but no light passes through Visual inspection of the coatings of metallic reinforcements should be the same as that made for polymeric reinforcements D.11 Reinforcement test method The reinforcement should be tested in accordance with a recognized test method For metallic reinforcements this should be done according to BS 1449-1:1983 For polymeric reinforcements this should be done according to BS 6906-1:1987 or ISO 10319:1992 Both the control samples and damaged samples should be tested The tensile strength, peak extension and the classified damage should be reported for each site damaged specimen and comparisons made with the properties of the control sample Annex E (normative) Determination of coefficient of friction and adhesion between fill and reinforcing elements or anchor elements for reinforced soil and anchored earth structures E.1 Reinforced soil elements E.1.1 General In order to determine the coefficient of friction and adhesion, tests should be carried out in a 300 mm size shear box with the element material fixed at the top of the lower half of the box and the fill sample occupying the top half only The test should be carried out following the procedure given in Annex C for the determination of the effective angle of internal friction and effective cohesion of earthworks materials However, the apparatus should in addition include a steel block fitting closely inside the lower half of the shear box and equal in height to it less the thickness of the reinforcing element material NOTE The flat toothed grid fitting the bottom of the shear box is not needed © BSI 06-1999 189 BS 8006:1995 E.1.2 Preparation of test specimens E.1.2.1 Element material should be cut to fit the interior plan shape of the shear box using a sufficient number of strips of such material abutting to completely fill the interior plan area without overlap They should be firmly fixed to the top of the steel block to the approval of the engineer so that the top face of the material is flush with the top edge of the lower half of the box and aligned so that shearing occurs in a direction parallel to the longitudinal axis of a reinforcing element E.1.2.2 A sample of the fill material to be used in the permanent works, of sufficient size to carry out the tests and within the range of moisture contents permitted for such material, should be sieved to obtain a test sample passing a 20 mm test sieve, of sufficient quantity after compaction to fill the top half of the shear box The permitted moisture content should be determined from the requirements of the Specification for Highway Works [1] The top and bottom of the shear box should be fixed together and the test sample of the sieved fill materials immediately placed and compacted in the top half of the box as described in Annex C E.1.3 Calculations The value of the coefficient of friction between the fill and the reinforcing element should be obtained by plotting the values of peak shear stress, obtained in the tests, against applied normal stress and by measuring the slope of the resulting straight line graph The adhesion between the fill and the reinforcement should be obtained by taking the shear stress corresponding with zero normal stress E.1.4 Information to be recorded The following additional information should be recorded for each test: a) normal stress applied in kN/m2; b) peak shear stress in kN/m2; c) strain at peak shear stress in %; d) moisture content of fill after test (for cohesive material) E.2 Anchor elements The coefficient of friction of the anchor shaft should be determined in the manner described in E.1.1 for reinforced soil elements using a shear box The contribution of the anchor or anchors to the pull-out resistance should be determined in accordance with the principles of soil mechanics augmented by pull-out tests where appropriate Annex F (normative) Trial constructions A level site should be prepared to provide a base area of about 10 m × m for a trial wall The height of the wall should be not less than m and the base area for the full height of the fill should be not less than m × m The sides of the fill should be sloped sufficiently to allow the compaction machinery to operate safely and effectively The fill materials should be placed and compacted in accordance with 9.2.3.2 The following aspects of performance should be monitored at the trial: a) ease of handling and storage; b) ease and accuracy of installation; c) damage, deformation or relative movements of components, including those of the facing units Annex G (informative) Propping forces The deformation of full height facings is controlled though the temporary use of props to support the face during placement of the fill The use of props is a simple construction technique and the horizontal load supported by the props PL may be determined from: K a ¾h t P L = -6 where ht is the height of the fill above the toe of the facing 190 © BSI 06-1999 BS 8006:1995 Prop forces less than those developed by the above equation can be achieved by following a specific construction sequence for a wall height H A proven sequence of releasing the props when the prop height hp > H/2 < H and where the toe of the wall is wedged includes the following steps: a) fill to level ht > H/2; b) remove the wedge (prop) supporting the toe; c) remove the prop With this construction sequence the horizontal propping force PL may be reduced to: K a ¾h t P L = 6h p When the structure is built on a soft foundation, the apparent rotation of the face into the fill may further reduce the prop force PL [26] © BSI 06-1999 191 BS 8006:1995 List of references (see 1.2) Normative references BSI publications BRITISH STANDARDS INSTITUTION, London BS 729:1971, Specification for hot dip galvanized coatings on iron and steel articles BS 882:1992, Specification for aggregates from natural sources for concrete BS 970, Specification for wrought steels for mechanical and allied engineering purposes BS 970-1:1991, General inspection and testing procedures and specific requirements for carbon, carbon manganese, alloy and stainless steels BS 1377, Methods of test for soils for civil engineering purposes BS 1377-3:1990, Chemical and electro-chemical tests BS 1377-4:1990, Compaction-related tests BS 1377-7:1990, Shear strength tests (total stress) BS 1377-8:1990, Shear strength tests (effective stress) BS 1377-9:1990, In-situ tests BS 1449, Steel plate, sheet and strip BS 1449-1:1983, Specification for carbon and carbon-manganese plate, sheet and strip BS 1449-2:1983, Specification for stainless and heat-resisting steel plate, sheet and strip BS 2569, Specification for sprayed metal coatings BS 2569-2:1965, Protection of iron and steel against corrosion and oxidation at elevated temperatures BS 2782, Methods of testing plastics BS 3416:1991, Specification for bitumen-based coatings for cold application, suitable for use in contact with potable water BS 3502, Symbols for plastics and rubber materials BS 3502-1:1991, Schedule for symbols for plastics BS 3502-2:1991, Schedule for symbols for rubbers BS 3502-3:1993, Schedule for symbols for compounding ingredients BS 3692:1967, Specification for ISO metric precision hexagon bolts, screws and nuts Metric units BS 4147:1980, Specification for bitumen-based hot-applied coating materials for protecting iron and steel, including suitable primers where required BS 4164:1987, Specification for coal-tar-based hot-applied coating materials for protecting iron and steel, including a suitable primer BS 4190:1967, Specification for ISO metric black hexagon bolts, screws and nuts BS 4360:1990, Specification for weldable structural steels BS 4449:1988, Specification for carbon steel bars for the reinforcement of concrete BS 4482:1985, Specification for cold reduced steel wire for the reinforcement of concrete BS 4483:1985, Specification for steel fabric for the reinforcement of concrete BS 4618, Recommendations for the presentation of plastics design data BS 5268, Structural use of timber BS 5400, Steel, concrete and composite bridges BS 5400-4:1990, Code of practice for design of concrete bridges BS 5930:1981, Code of practice for site investigations BS 5975:1982, Code of practice for falsework BS 6031:1981, Code of practice for earthworks BS 6105:1981, Specification for corrosion-resistant stainless steel fasteners BS 6349, Maritime structures 192 © BSI 06-1999 BS 8006:1995 BS 6906, Methods of test for geotextiles BS 6906-1:1987, Determination of the tensile properties using a wide width strip BS 6906-5:1991, Determination of creep BS 6906-8:1991, Determination of sand-geotextile frictional behaviour by direct shear BS 8002:1994, Code of practice for earth retaining structures BS 8004:1986, Code of practice for foundations BS 8110, Structural use of concrete BS 8110-1:1985, Code of practice for design and construction BS 8110-2:1985, Code of practice for special circumstances BS 8110-3:1985, Design charts for singly reinforced beams, doubly reinforced beams and rectangular columns BS EN 10025:1993, Hot rolled products of non-alloy structural steels Technical delivery conditions BS EN 30320:1993, Geotextiles —Identification on site DD ENV 1997, Eurocode 7: Geotechnical design DD ENV 1997-1:1995, General rules ISO publications INTERNATIONAL ORGANIZATION FOR STANDARDIZATION (ISO), Geneva (All publications are available from BSI Customer Services, Publications.) ISO 10319:1992, Geotextiles — Tensile test by wide-width method ISO 10321:1992, Geotextiles — Tensile test for joints/seams by wide-width method Other references [1] DEPARTMENT OF TRANSPORT, Manual of Contract Documents for Highway Works, Specification for Highway Works, Department of Transport London: HMSO, 1993, [21] WU, P and SMITH, R.J.H., Reinforced Earth Marine Wall Experience in Canada and United Kingdom, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 147-154 [25] WORRALL, P.K., Reinforced Earth Abutments and Approach Ramps on Compressible Soils at Burton-on-Trent, Highways and Transportation, March, 1989, 5-8 [31] SIMS, FA and BRIDLE, R.J., Bridge Design in Areas of Mining Subsidence, Journal Institution of Highway Engineers, 1966, 13, November, 19-34 [32] ICE, Ground Subsidence, Institution of Civil Engineers, Thomas Telford, London, 1977 [33] JONES, C.J.F.P and SPENCER, W.J., The Implications of Mining Subsidence for Modern Highway Structures, Large Ground Movements and Structures, Edited by J.O Geddes, Pentech Press, UK, 1978, 515-526 [80] YOUNG, O.C and O’REILLY, M., A Guide to Design Loadings for Buried Rigid Pipes, Transport and Road Research Laboratory, 1983 Informative references BSI publications BRITISH STANDARDS INSTITUTION, London BS 2782, Methods of testing plastics BS 3502:1991, Symbols for plastics and rubber materials BS 4618, Recommendations for the presentation of plastics design data BS 8081:1989, Code of practice for ground anchorages PD 6533:1993, Guide to methods for assessing the durability of geotextiles An interim document BS EN ISO 9002:1994, Quality systems — Model for quality assurance in production, installation and servicing © BSI 06-1999 193 BS 8006:1995 Other references [2] WILLIAMS, D and SANDERS, R.L., Design of Reinforced Embankments for Great Yarmouth By-Pass, Proceedings Eleventh International Conference on Soil Mechanics and Foundation Engineering, San Francisco, 1985, 3, 1811–1815 [3] INGOLD, T.S A Laboratory Investigation of Grid Reinforcements in Sand, ASTM Geotechnical Testing Journal, 1983, 6, no.3, 101–111 [4] INGOLD, T.S., A Laboratory Investigation of Grid Reinforcements in Clay, ASTM Geotechnical Testing Journal, 1983, 6, no.3, 112–119 [5] SCHLOSSER, F and ELIAS, V., Friction in Reinforced Earth, Symposium on Earth Reinforcement, American Society of Civil Engineers, Pittsburgh, 1978, 735–763 [6] SCHLOSSER, F and GUILLOUX, A., Le Frottement Sol-Amature dans les Ouvrages en Terre Armée, Proceedings International Conference on Soil Reinforcement: Reinforced Earth and Other Techniques, Ecole Nationale Des Ponts et Chaussees, Paris, 1979, 1, 151–156 [7] SCHLOSSER, F., Note Technique La Terre Armée, Laboratoire Central des Ponts et Chaussees, 1973 [8] JONES, C.J.F.P and SIMS F.A., Earth Pressures Against the Abutments and Wingwalls of Standard Motorway Bridges, Geotechnique, 1975, 25, no.4, 731–742 [9] INGOLD, T.S., The Design of Reinforced Soil Walls by Compaction Theory, The Structural Engineer, 1983, 61a, no.7, 205–212 [10] MINISTERE DES TRANSPORTS, Les Ouvrages en Terre Armée: Recommendations et Règles de 1’Art, Direction des Routes et de la Circulation Radar, Paris, France, 1979 [11] WEST, G and AERIAL, M.P., An Evaluation of Unburnt Colliery Shale as Fill for Reinforced Earth Structures, Research Report 97, Transport and Road Research Laboratory, 1986 [12] RAINBOW, A.K.M., An Investigation of Some Factors Influencing the Suitability of Minestone as the Fill in Reinforced Earth Structures, British Coal Minestone Services, 1986 [13] TATSUOKA, F., MISSATA, O., TATEYAMA, M., NAKAMURA, K., JAMURA, Y., LING, H., IWASAKI, K and YAMANOUCHI, H., Reinforcing Clay Slopes with a Non-Woven Geotextile, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 141–146 [14] BISHOP, A.W., The Strength of Soils as Engineering Materials, Geotechnique, 1966, 16, 91–130 [15] CORNFORTH, D.H., Prediction of Drained Strength of Sands from Relative Density Measurements, Evaluation of Relative Density and its Role in Geotechnical Projects Involving Cohesionless Soils, American Society for Testing and Materials, Special Technical Publication No.523, 1973, 281–303 [16] LAWSON, C.R., Soil Reinforcement with Geosynthetics, Proceedings Workshop on Applied Ground Improvement Techniques, Bangkok, Asian Institute of Technology, 1992, 1–74 [17] CIRIA, Rationalisation of Safety and Serviceability Factors in Structural Codes, Construction Industry Research and Information Association, Report No.63, London, 1977 [18] MURRAY, R.T., Factor of Safety Considerations in Reinforced Soil, The Applications of Polymeric Reinforcement in Soil Retaining Structures, Edited by J.M Jarrett and A McGown, Kluwer Academic Publishers, NATO ASI Series, 1989, 147, 507–553 [19] SMITH, R.J.H., Reinforced and Anchored Earth, Ground Engineering, October, 1986, 7–10 [20] SMITH, R.J.H and WORRALL, P.K., Foundation Options for Reinforced Earth on Poor Ground, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 427–432 [22] RODRIGUES, R.A and VILLADRROEL, J.M., Reinforced Earth Abutments Founded on Very Compressible Soil, Autoroute de Menton, Bulletin Liaison Laboratoire de Ponts et Chaussees, Paris, 1971 [23] BRADY, K.C., Reinforced and Anchored Earth, Ground Engineering, 1986, 19, no.7, 7–10 [24] BRADY K.C., Performance of a Reinforced Earth Bridge Abutment at Carmarthen, Transport and Road Research Laboratory Research Report 111, 1987 [26] JONES, C.J.F.P and EDWARDS, L.W., Reinforced Earth Structures Situated on Soft Foundations, Geotechnique, June, 1980, 30, no.2, 207–211 [27] KEMPTON, G T., ENWISTLE, R.W and BARCLAY, M.J., An Anchored Fill Harbour Wall Using Synthetic Fabrics, Proceedings Institution of Civil Engineers, April, 1985, Part 1, 575–587 [28] JONES, C.J.F.P., Review of Effects of Mining Subsidence on Reinforced Earth, TRRL Contractor Report 123, Transport and Road Research Laboratory, 1989 194 © BSI 06-1999 BS 8006:1995 [29] MURRAY, R.T., JONES, C.J.F.P and SMITH R.J.H., Reinforced Soils in Cases of Mining Subsidence, Proceedings Twelfth International Conference on Soil Mechanics and Foundation Engineering, Rio De Janerio, Balkema, 1989, 2, 1285–1295 [30] MOULTON, L.K., GANGORAO, H.V.S., and HALVORSEN, G.T., Tolerable Movement Criteria for Highway Bridges, Report No FHWA/RD-81/162, Federal Highway Administration, Washington, 1982 [34] GASSLER, G., In-Situ Techniques of Reinforced Soil, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 185–196 [35] SCHLOSSER, F., Behaviour and Design of Soil Nailing, Proceedings International Symposium on Recent Developments in Ground Improvement Techniques, Bangkok, Balkema, 1982, 399–413 [36] SCHLOSSER, F and DE BUHAN, P, Theory and Design Related to the Performance of Reinforced Soil Structures, State-of-the-Art Review, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 1–14 [37] RDGC, Renforcement des Sols par Clouage: Programme Clouterre, Projets Nationaux de Recherche Developpement en Genie Civil, Paris, February, 1991 [38] MURRAY, R.T., Fabric Reinforcement of Embankments and Cuttings, Proceedings Second International Conference on Geotextiles, Las Vegas, 1982, 3, 707–713 [39] JEWELL, R.A., PAINE, N and WOODS, R.I., Design Methods for Steep Reinforced Embankments, Polymer Grid Reinforcement, Thomas Telford, London, 1985, 70–81 [40] MURRAY, R.T., WRIGHTMAN, J and BURT, A., Use of Fabric Reinforcement for Reinstating Unstable Slopes, TRRL Supplementary Report 751, Transport and Road Research Laboratory, 1982 [41] LESCHINSKY, D and VOLK, J.C., Stability Charts for Geotextile Reinforced Walls, Transportation Research Record 1031, 1986, 5–16 [42] SEGRESTIN, P., FIORENTINI, F and SPITI, F., Design of Sloped Retaining Structures or Slope Stabilization With Reinforced Earth, Italian Building and Construction, January, 1991, 73–82 [43] DEPARTMENT OF TRANSPORT, Design Methods for the Reinforcement of Highway Slopes by Reinforced Soil and Soil Nailing Techniques, Design Manual for Roads and Bridges: Part 4, HA 68/94, Department of Transport, HMSO, 1994 [44] GREENWOOD, J., Stability Analysis of Reinforced Slopes, Highways and Transportation, October, 1986, 26–28 [45] GREENWOOD, J., Design Approach for Slope Repairs and Embankment Widening, Reinforced Embankments: Theory and Practice, Edited by D.A Shercliff, Thomas Telford Ltd, London, 1990, 51–61 [46] TAYLOR, D.W., Fundamentals of Soil Mechanics, Wiley, New York, 1948 [47] LESCHINSKY, D and BOEDECKER, R.H., Geosynthetic Reinforced Earth Structures, Journal Geotechnical Engineering Division, American Society of Civil Engineers, 1989, 115, no 10, 1459–1478 [48] BRIDLE, R.J and BARR, B.I.G., The Analysis and Design of Soil Nails, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 249–254 [49] MURRAY, R.T., Reinforcement Techniques in Repairing Slope Failures, Polymer Grid Reinforcement, Thomas Telford, London, 1985, 47–53 [50] LIZZI, F., The “Pali Radice” (Root Piles) — A State-of-the-Art Report, Proceedings International Symposium on Recent Developments in Ground Improvement Techniques, Bangkok, Balkema, 1982, 417–432 [51] LIZZI, F., The “Reticolo di Pali Radice” (Reticulated Root Piles) for the Improvement of Soil Resistance, Proceedings Eighth European Conference on Soil Mechanics and Foundation Engineering, Helsinki, 1983, 2, 521–524 [52] GASSLER, G and GUDEHUS, G., Soil Nailing — Statistical Design, Proceedings Eighth European Conference on Soil Mechanics and Foundation Engineering, Helsinki, 1983, 2, 491–494 [53] GUILLOUX, A and SCHLOSSER, F., Soil Nailing: Practical Applications, Proceedings International Symposium on Recent Developments in Ground Improvement Techniques, Bangkok, Balkema, 1982, 389–398 [54] CARTIER, G., Examples of the Use of Soil Nailing for the Stabilisation of Unstable Slopes, Bulletin Liaisons Laboratoire Central des Ponts et Chaussées, 1986, 145, 5–12 [55] BRUCE, D.A and JEWELL, R.A., Soil Nailing; Application and Practice — Part 1, Ground Engineering, 1986, 19, 10–15 [56] BRUCE, D.A and JEWELL, R.A., Soil Nailing; Application and Practice — Part 2, Ground Engineering, 1987, 20, 21–38 © BSI 06-1999 195 BS 8006:1995 [57] JEWELL, R.A., Soil Nailing, General Report, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 197–200 [58] BRIDLE, R.J and MYLES, B., A Machine for Soil Nailing — Process and Design, Ecole Nationale des Ponts et Chaussees, Paris, October, 1991 [59] STOCKER, M.F., KORBER, G.W., GASSLER, G and GUDEHUS, G., Soil Nailing, Proceedings International Conference on Soil Reinforcement: Reinforced Earth and Other Techniques, Ecole Nationale Des Ponts et Chaussees, Paris, 1979, 469–474 [60] BANG, S., SHEN, C.K and ROMSTAD, K.M., Analysis of an Earth- Reinforcing System for Deep Excavation, Transportation Research Record 749, National Academy of Sciences, Washington, 1980 [61] JURAN, I., BAUDRAND, G., FARRAG, K and ELIAS, V., Kinematical Limit Analysis for Design of Soil-Nailed Structures, Journal Geotechnical Engineering Division, American Society of Civil Engineers, 1990, 116, no.1, 54–73 [62] GASSLER, G., Soil Nailing — Theoretical Basis and Practical Design, Proceedings International Symposium on Theory and Practice of Earth Reinforcement, Fukuoka, Balkema, 1988, 283–288 [63] JEWELL, R.A and PEDLEY, M.J., Soil Nailing Design: The Role of Bending Stiffness, Ground Engineering, 1990, 30–36 [64] BISHOP, A.W., The Use of the Slip Circle in the Stability of Slopes, Geotechnique, 1955, 5, –17 [65] JANBU, N., Application of Composite Slip Circles for 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Proceedings Specialty Conference on Performance of Earth and Earth-Supported Structures, Purdue, American Society of Civil Engineers, 1972, 2, 1–54 [72] BUSH, D.I., JENNER, C.J and BASSETT, R.H., The Design and Construction of Geocell Foundation Mattresses Supporting Embankments over Soft Ground, Geotextiles and Geomembranes, Elsevier, 1989, 9, no.1, 83–98 [73] JENNER, C.G., BASSETT, R.H and BUSH, D.I., The Use of Slip Line Fields to Assess Improvement in Bearing Capacity of Soft Ground by a Cellular Foundation Mattress Installed at the Base of an Embankment, Proceedings International Symposium on Theory and Practice of Earth Reinforcement, Fukuoka, Balkema, 1988, 209–214 [74] INGOLD, T.S and MILLER, K.S., Short, Intermediate and Long Term Stability of Geotextile Reinforced Embankments over Soft Clays, Proceedings Third International Conference on Geotextiles, Vienna, Balkema, 1986, 2, 337–342 [75] REID, W.M and BUCHANAN, N.W., Bridge Approach Support Piling, Proceedings Conference on Piling and Ground Treatment, London, Thomas Telford, 1984, Paper 21, 267–274 [76] JONES, C.J.F.P., LAWSON, C.R and AYRES, D.J., Geotextile Reinforced Piled Embankments, Proceedings Fourth International Conference on Geotextiles, Geomembranes and Related Products, The Hague, Balkema, 1990, 1, 155–160 [77] CARLSSON, B., Armerad Jord, Terranova, Sweden, 1987 [78] SPANGLER, M.G and HANDY, R.L., Soil Engineering, Intext Educational Publishers, New York, 1973 [79] JOHN, N.W.M., Geotextiles, Blackie, Glasgow, 1987 [81] LEONARD, J.W., Tension Structures, McGraw-Hill, New York, 1988 [82] KEMPTON, G.T., The Use of Reinforcement Geotextiles to Support Road Embankments over Areas Subjected to Mining Subsidence, Highways and Transportation, December, 1992, 21–31 196 © BSI 06-1999 BS 8006:1995 [83] ELIAS, V and MCKITTERICK, D.P., Special Uses of Reinforced Earth in the United States, Proceedings International Conference on Soil Reinforcement: Reinforced Earth and Other Techniques, Ecole Nationale Des Ponts et Chaussées, Paris, 1979, 1, 256–260 [84] PARRY, H.J., Coping with Fife’s Mining Industrial Heritage, Municipal Engineer, 1983, 110, 778, 231–240 [85] JONES, C.J.F.P., Construction Influences on the Performance of Reinforced Soil Structures, State-of-the-Art Review, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 97–117 [86] GRIFFITHS, I.F., Reinforced Earth Trial Wall Using Chalk Fill at Paulsgrove, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 89–90 [87] BOOT, G.T., The Results of Pull-Out Tests Carried Out in pfa on a Reinforced Earth Structure in South Wales, Performance of Reinforced Soil Structures, Edited by A McGown, K.C Yeo and K.Z Andrewes, Glasgow, Thomas Telford, 1990, 85–86 [88] JONES, C.J.F.P., CRIPWELL, J.B and BUSH, D.I., Reinforced Earth Trial Structure for Dewsbury Ring Road, Proceedings Institution of Civil Engineers, April, 1990, Part 1, 88, 321–345 [89] JONES, C.J.F.P., MCGOWN, A and VARNEY, D., Construction Methods, Specifications and Economics, The Applications of Polymeric Reinforcement in Soil Retaining Structures, Edited by J.M Jarrett and A McGown, Kluwer Academic Publishers, NATO ASI Series, 1989, 147, 573–613 [90] COPPIN, N.J and RICHARDS, I.E., Use of Vegetation in Civil Engineering, Butterworths, 1990 [91] DEPARTMENT OF TRANSPORT, Trunk Road and Motorway Structures — Records and Inspection, Trunk Road Management and Maintenance Notice No TRMM2/88, Department of Transport, 1988 [92] JONES, C.J.F.P., The York Method of Reinforced Earth Construction, ASCE Symposium on Earth Reinforcement, Pittsburgh, 1978, 501–528 [93] JONES, C.J.F.P., Earth Reinforcement and Soil Structures, Butterworths, London, 1985 [94] PAUL, J., Economics and Construction of Blast Embankments Using “Tensar” Geogrids, Polymer Grid Reinforcement, Thomas Telford, London, 1985, 191–197 [95] GÖBEL, C., HOY, G and 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Waterways Experiment Station, 1977 [100] CHRISTOPHER, B.R and HOLTZ, R.D., Geotextile Design and Construction Guidelines, Federal Highway Administration, National Highways Institute, Report No FHWA-HI-90-001, 1989 [101] GILCHRIST, A.J.T., The Use of High Strength Geogrids as a Surface Protection Membrane in Areas of Shallow Mineworkings, Proceedings Second International Conference on Construction in Areas of Abandoned Mineworkings, University of Edinburgh, 1988, 237–241 [102] KEMPTON, G.T and JONES, C.J.F.P., The Use of High Strength Link Geotextiles Over Piles and Voids, Proceedings International Symposium on Earth Reinforcement Practice, Fukuoka, Balkema, 1992, 613–618 [103] EPA, Lining of Waste Containment and Other Impoundment Facilities, United States Environmental Protection Agency, Report No EPA/600/2-88/052, 1988 © BSI 06-1999 197 BS 8006:1995 BSI — British Standards Institution BSI is the independent national body responsible for preparing British Standards It presents the UK 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Facing Standard Concrete BS 8110; BS 5400-4 Steel sheet BS 1449-1 Steel grids and meshes BS 4482; BS 4483; BS 4449 Timber BS 5268; BS 5975 (temporary works) Galvanizing BS 729 3.3.2 Soft facings... A4-70 700 of BS 6105:1981 420 700 Alloy steel to BS 3692:1967 30 © BSI 06-1999 BS 8006: 1995 Figure — Types of seams © BSI 06-1999 31 BS 8006: 1995 Table 11 — Properties of dowels and rods up to