2 Revival of withdrawn/obsolete geotechnical standards Several important geotechnical codes of practice were withdrawn in March 2010 on the introduction of the Structural Eurocodes, including: BS 8004:1986, Code of practice for foundations BS 8002:1994, Code of practice for earth retaining structures The following standard remained but was largely incompatible with Eurocode 7: BS 8081:1989, Code of practice for ground anchorages (renamed grouted anchors ) The revival of these standards was sponsored by HS2 because they want to put them out with contracts for enabling work starting in June Additional (related) work sponsored by HS2 includes: Revision of CIRIA C580 (2003), Embedded retaining walls guidance for economic design Creation of PAS 8812, Guide to the application of European Standards in temporary works design (co-sponsored by the Temporary Works Forum, TWf) Other relevant (related) work includes: Revision of BS 5930:1999+A2:2010, Code of practice for site investigations (renamed ground investigations ) Relationship between British Standards and Eurocode 7 MODIFIED AFTER BOND AND HARRIS (2008) 2
3 Presentational conventions for the new geotechnical BSs The provisions of this standard are presented in roman (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb is should. Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element. Foreword to BSs 8002, 8004, and 8081 should expresses recommendations of these standard may expresses permissibility (e.g. as an alternative to the primary recommendation) can expresses possibility (e.g. a consequence of an action or an event) Notes and commentaries are provided throughout the text of this standard. Notes give references and additional information that are important but do not form part of the recommendations. Commentaries give background information. Note that the word shall is NOT used in BSs 8002, 8004, or 8081 shall is used in Eurocode 7 (BS EN and -2) BS 8002, 8004, AND 8081 FOREWORDS Eurocode 7 timeline
5 Changing contents of BS 8004 for foundations BS 8004:1986 (186 pp) Foreword (1 pp) 1. General (7 pp) 2. Design of foundations (27 pp) 3. Shallow foundations (5 pp) 4. Deep and subaqueous foundations (13 pp) 5. Cofferdams and caissons (17 pp) 6. Geotechnical processes: groundwater lowering, grouting and other methods of changing the ground characteristics in situ (38 pp) 7. Pile foundations (32 pp) 8. Tide work, underwater concreting and diving (6 pp) 9. Site preparation for foundation work (6 pp) 10. Durability of timber, metal and concrete structures (9 pp) 11. Safety precautions (10 pp) Appendices (10 pp) DPC BS 8004:2015 (101 pp) Foreword (1 pp) 1. Scope (1 pp) 2. Normative references (4 pp) 3. Terms and definitions (1 pp) 4. General rules (25 pp) 5. Spread foundations (11 pp) 6. Pile foundations (42 pp) Annexes (*normative) A. *Underpinning (4 pp) B. *Helical pile foundations (4 pp) C. Specific formations (2 pp) Bibliography (5 pp) BS 8004:1986 AND 2015 Changing contents of BS 8002 for earth retaining structures BS 8002:1994 (134 pp) Foreword (2 pp) 1. Introduction (6 pp) 2. Data for design (12 pp) 3. Design philosophy, design method and earth pressure (24 pp) 4. Design of specific earth retaining structures (71 pp) Annexes (*normative) A. *Graphs for K a and K p (8 pp) B. Traditional design methods for embedded walls (3 pp) C. Bibliography (4 pp) DPC BS 8004:2015 (92 pp) Foreword (1 pp) 1. Scope (1 pp) 2. Normative references (4 pp) 3. Terms and definitions (1 pp) 4. General rules (31 pp) 5. Gravity retaining walls (16 pp) 6. Semi-gravity retaining walls (7 pp) 7. Embedded retaining walls (14 pp) 8. Cofferdams, basements, and strutted excavations (4 pp) Annexes (*normative) A. *Deadman anchors (5 pp) B. Specific formations (1 pp) C. Archeological finds (1 pp) Bibliography (3 pp) BS 8002:1994 AND
6 Changing contents of BS 8081 for grouted anchors BS 8081:1989 (177 pp) Foreword (1 pp) Introduction (1 pp) 1. Scope (1 pp) 2. Definitions (6 pp) 3. Symbols (2 pp) 4. Responsibilities (1 pp) 5. Site investigation (5 pp) 6. Design (14 pp) 7. Material and components (10 pp) 8. Corrosion and corrosion protection (20 pp) 9. Stressing equipment (1 pp) 10. Construction (10 pp) 11. Testing (13 pp) 12. Maintenance (1 pp) 13. Legal aspects (2 pp) Appendices (73 pp) (135 pp) Foreword (1 pp) 1. Scope (1 pp) 2. Normative references (2 pp) 3. Terms, definitions and symbols (9 pp) 4. General recommendations (5 pp) 5. Limit states (1 pp) 6. Design situations (1 pp) 7. Design considerations (3 pp) 8. Ultimate limit state design (1 pp) 9. Serviceability limit state design (1 pp) 10. Structural design (1 pp) 11. Anchor design (4 pp) 12. Materials (6 pp) 13. Durability (12 pp) 14. Execution (10 pp) 15. Considerations relating to testing (1 pp) 16. Maintenance (1 pp) 17. Reporting (1 pp) Annexes A-I (informative) (69 pp) Bibliography (4 pp) BS 8081:1989 AND 2015 Outline of talk 10 mins Andrew Purpose/structure of the revised British standards BS 8004 Foundations and BS 8002 Earth retaining structures Caesar BS 8081 Grouted anchors Devon BS 8081 Grouted anchors REVISION OF BS 8002, 8004, AND mins Summary of key points 6
11 BS 8081:2015 Relationship T W and F serv;k BS 8081:1989 T W found from overall stability analysis (L.E.M.) with FoS up to 1.5 i.e T W = 1.5 x T (unfactored SLS condition) T = the derived axial force that the anchor provides to maintain equilibrium (unfactored) BS 8002:2015 F D = F serv;k = SD x F x P SLS 1.5 x P SLS From L.E.M. analysis Where;- P SLS = design axial force that the anchor provides to prevent a SLS (i.e. unfactored)(= T) BS 8081:2015 Since compliant with BS 8002:2015 through consideration of stability of supported structure at serviceability limit state;- T W F serv;k BS 8081:2015 Derivation of R GG;k BS 8081:2015 R GG;k = min R GG;calc x f eff ; R GG;m Îgg Where;- R GG;calc = calculated ultimate ground/grout interface resistance R GG;m = measured ultimate ground/grout interface resistance 11
13 BS 8081:2015 Concluding remarks Objectives achieved in revision Reduction in size of document NCCI with respect to appropriate ENs and ECs Maintain current practice of sizing fixed anchor lengths by single stress reduction factor (FoS?) Retained and updated valuable information from BS8081:1989 in Annexes as much as possible Incorporated Testing Annex to provide guidance pending the publication of EN ISO Outline of talk 10 mins Andrew Purpose/structure of the revised British standards BS 8004 Foundations and BS 8002 Earth retaining structures Caesar BS 8081 Grouted anchors Devon BS 8081 Grouted anchors REVISION OF BS 8002, 8004, AND mins Summary of key points 13
19 BS 8081:2015 Code of practice for grouted anchors DPC BS8081:2015, Section 16 Maintenance Subject to minor revision to incorporate reference to published literature covering the grading of anchors heads subject to corrosive degradation DPC BS8081:2015, Section 17 Reporting Subject to minor revision to incorporate the concept of the Geotechnical Feedback Report (GFR) or close-out report as per DPC BS8002:2015 and DPC BS8004:2015. This report should include; a record of anchor construction and any changes to the design results of monitoring and testing conducted during construction BS 8081:2015 Code of practice for grouted anchors This part of the presentation will cover: Brief introduction Sections within DPC BS8081:2015; Materials Durability Execution Considerations relating to testing Maintenance Reporting Annexes A-I (informative) Closing remarks 19
21 BS 8081:2015 Code of practice for grouted anchors Closing remarks The drafting of DPC BS8081:2015 was carried out within strict guidelines and time constraints stipulated by BSI The overall objective was to retain the information, within the original document, considered essential to the future of ground anchor practice It was explicitly specified that the revised document should contain noncontradictory complimentary information The revised document is compatible with EC7 and associated Euronorms In the absence of EN ISO , Annex G will provide the necessary guidance on testing of anchors The acceptance criteria for the testing of anchors are referenced in the UK NA to EC7 The structure and layout is comparable with BS8004 and BS8002 and facilitates the structure to be adopted in the revision of EC7 in 2020 The document is still evolving, an internal review by the technical authors has generated 99 comments/amendments Outline of talk 10 mins Andrew Purpose/structure of the revised British standards BS 8004 Foundations and BS 8002 Earth retaining structures Caesar BS 8081 Grouted anchors Devon BS 8081 Grouted anchors REVISION OF BS 8002, 8004, AND mins Summary of key points 21
22 BS 8004:2015 and BS 8002:2015, Codes of practice for Foundations (101pp) Foreword (1pp) 1. Scope (1pp) 2. Normative references (4pp) 3. Terms and definitions (1pp) 4. General rules (25/31pp) Earth retaining structures (92pp) 5. Spread foundations (11pp) 5. Gravity retaining walls (16pp) 6. Pile foundations (42pp) 6. Semi-gravity retaining walls (7pp) Annexes (*normative) 7. Embedded retaining walls (14pp) 8. Cofferdams, basements, and strutted excavations (4 pp) A* Underpinning (4pp) A* Deadman anchors (5pp) B* Helical pile foundations (4pp) B. Specific formations (1pp) C. Specific formations (2pp) C. Archaeological finds (1pp) Bibliography (5/3pp) CONTENTS OF BS 8004 AND BS 8002 General rules key topics for BS 8004 Ground investigation Minimum number and depth of exploration points for low-rise buildings Ground parameters Suggested values for weight density of coarse and fine soils and fill Updated guidance on selecting cv for coarse and fine soils Standardizing terminology for stiffness values (secant, tangent, small-strain, large strain) Default expressions for G sec and G 0 ( in the absence of reliable test values ) Partial factors Proposes,cv = 1.0 (to overcome ambiguity in Eurocode 7) Reporting Confirms Eurocode 7 s requirements for GIR and GDR Recommends production of Geotechnical Feedback Report (aka close-out report ) 22
d0d94e66b7