Revision History Revision Description Date P1 Planning 24/07/14

Transcription

1 45 CLARENDON ROAD, LONDON W11 Structural Engineer s Specification ISSUE 1 PLANNING July 2014 Revision History Revision Description Date P1 Planning 24/07/14

2 CONTENTS D20 EXCAVATING AND FILLING.. 1 D30 PILING. 5 D40 EMBEDDED RETAINING WALLS. 10 E05 IN SITU CONCRETE CONSTRUCTION GENERALLY. 18 E10 MIXING/ CASTING/ CURING IN SITU CONCRETE.. 20 E20 FORMWORK FOR IN SITU CONCRETE.. 26 E30 REINFORCEMENT FOR IN SITU CONCRETE.. 28 E41 WORKED FINISHES TO IN SITU CONCRETE.. 29 G10 STRUCTURAL STEEL FRAMING.. 30 G20 CARPENTRY/ TIMBER FRAMING / FIRST FIXING 36 P31 HOLES, CHASES, COVERS AND SUPPORTS FOR SERVICES.. 40 APPENDIX A BP PERFORMANCE SPECIFICATIONS FOR PLANNING 42

3 1 D20 EXCAVATING AND FILLING To be read with Preliminaries/ General conditions and in conjunction with the Stage Design Statement by BP. GENERALLY / THE SITE 110 SITE INVESTIGATION - Report: Prepared by Chelmer Site investigations Ltd, available. 145 VARIATIONS IN GROUND WATER LEVEL To be monitored by contractor. - Give notice: If levels encountered are significantly different from levels in the site investigation report or previously measured. 150 EXISTING SERVICES, FEATURES AND STRUCTURES - Services: See section A12 for locations. - Site features to be retained: See section A12 for details. - Structures: See section A34 for details of protection. CLEARANCE/ EXCAVATING 168 SITE CLEARANCE - Timing: Before topsoil stripping, if any. - General: Clear site of rubbish, debris and vegetation. Do not compact topsoil. 170 REMOVING SMALL TREES, SHRUBS, HEDGES AND ROOTS - Identification: Clearly mark trees to be removed. - Small trees, shrubs and hedges: Cut down - Roots: Grub up and dispose of without undue disturbance of soil and adjacent areas - Safety: Comply with HSE/ Arboriculture and Forestry Advisory Group safety leaflets. 225 HANDLING TOPSOIL - Aggressive weeds: - Species: Included in the Weeds Act, section 2 or the Wildlife and Countryside Act, Schedule 9, part II. - Give notice: Obtain instructions before moving topsoil. - Contamination: Do not mix topsoil with: - Subsoil, stone, hardcore, rubbish or material from demolition work. - Other soil or material containing aggressive weeds, sharps, plastics and non-soil forming materials and notifiable animal or plant diseases. - Oil, fuel, cement or other substances harmful to plant growth. - Other classifications of topsoil. - Multiple handling: Keep to a minimum. Use topsoil immediately after stripping. - Wet conditions: Handle topsoil in the driest condition possible. Do not handle during or after heavy rainfall or when it is wetter than the plastic limit as defined by BS 3882, Annex N ADJACENT EXCAVATIONS - Requirement: Where an excavation encroaches below a line drawn at an angle from the nearest formation level of another higher excavation, the lower excavation, all work within it and backfilling thereto, must be completed before the higher excavation is made. - Angle of line below horizontal: 45 degrees.

4 2 250 PERMISSIBLE DEVIATIONS FROM FORMATION LEVELS - Beneath mass concrete foundations: ±25 mm. - Beneath ground bearing slabs and r.c. foundations: ±15 mm. - Embankments and cuttings: ±50 mm. - Ground abutting external walls: ±50 mm, but such as to ensure that finished level is not less than 150 mm below dpc. 260 INSPECTING FORMATIONS - Give notice: Make advance arrangements for inspection of formations for foundations and filling formations. - Preparation: Just before inspection remove the last 150 mm of excavation. - Trim to required profiles and levels, and remove loose material. - Seal: Within 4 hours of inspection, seal formations with concrete 270 FOUNDATIONS GENERALLY - Give notice if: - A natural bearing formation of undisturbed subsoil is not obtained at the depth shown on the drawings. - The formation contains soft or hard spots or highly variable material. 310 UNSTABLE GROUND - Generally: Ensure that the excavation remains stable at all times. - Give notice: Without delay if any newly excavated faces are too unstable to allow earthwork support to be inserted. - Take action: If instability is likely to affect adjacent structures or roadways, take appropriate emergency action. 320 RECORDED FEATURES - Recorded foundations, beds, drains, manholes, etc: Break out and seal drain ends. - Contaminated earth: Remove and disinfect as required by local authority. 330 UNRECORDED FEATURES - Give notice: If unrecorded foundations, beds, voids, basements, filling, tanks, pipes, cables, drains, manholes, watercourses, ditches, etc. not shown on the drawings are encountered. 360 EXCESS EXCAVATION - Excavation taken wider than required: - Backfill: GEN 1 concrete as specification E10/ Excavation taken deeper than required: - Backfill: GEN 1 concrete as specification E10/105. DISPOSAL OF MATERIALS 415 EXCAVATED TOPSOIL REMOVAL - General: Remove from site. 450 WATER - Generally: Keep all excavations free from water until: - Formations are covered. - Below ground constructions are completed. - Basement structures and retaining walls are able to resist leakage, water pressure and flotation. - Drainage: Form surfaces of excavations and fill to provide adequate falls. - Removal of water: Provide temporary drains, sumps and pumping as necessary. Do not pollute watercourses with silt laden water.

5 3 454 GROUND WATER LEVEL, SPRINGS OR RUNNING WATER - Springs/ Running water: Give notice immediately if encountered. 457 PUMPING - General: Do not disturb excavated faces or stability of adjacent ground or structures. - Pumped water: Discharge without flooding the site or adjoining property. - Sumps: Construct clear of excavations. Fill on completion. - Locations: submit proposals. FILLING 500 PROPOSED FILL MATERIALS - Details: Submit full details of proposed fill materials to demonstrate compliance with specification, including: - Type and source of imported fill. - Proposals for processing and reuse of material excavated on site. - Test reports as required elsewhere. - Timing: at least 21 days before starting filling. 510 HAZARDOUS, AGGRESSIVE OR UNSTABLE MATERIALS - General: Do not use fill materials which would, either in themselves or in combination with other materials or ground water, give rise to a health hazard, damage to building structures or instability in the filling, including material that is: - Frozen or containing ice. - Organic. - Contaminated or noxious. - Susceptible to spontaneous combustion. - Likely to erode or decay and cause voids. - With excessive moisture content, slurry, mud or from marshes or bogs. - Clay of liquid limit exceeding 80 and/or plasticity index exceeding Unacceptable, class U2 as defined in the Highways Agency Specification for highway works, clause FROST SUSCEPTIBILITY - General: Except as allowed below, fill must be non-frost-susceptible as defined in Highways Agency Specification for highway works, clause Test reports: If the following fill materials are proposed, submit a laboratory report confirming they are non-frost-susceptible: - Fine grained soil with a plasticity index less than 20%. - Coarse grained soil or crushed granite with more than 10% retained on a mm sieve. - Crushed chalk. - Crushed limestone fill with average saturation moisture content in excess of 3%. - Burnt colliery shale. - Frost-susceptible fill: May only be used within the external walls of buildings below spaces that will be heated. Protect from frost during construction 530 PLACING FILL - Surfaces of excavations and areas to be filled: Free from loose soil, topsoil, organic material, rubbish and standing water. - Freezing conditions: Do not place fill on frozen surfaces. Remove material affected by frost. Replace and recompact if not damaged after thawing. - Adjacent structures, membranes and buried services: - Do not overload, destabilise or damage. - Submit proposals for temporary support necessary to ensure stability during filling.

6 4 - Allow 14 days (minimum) before backfilling against in situ concrete structures. - Layers: Place so that only one type of material occurs in each layer. - Earthmoving equipment: Vary route to avoid rutting. 535 COMPACTION - General: Compact fill not specified to be left loose as soon as possible after placing. - After compaction: Surface of each layer must be well closed, showing no movement under compaction plant, and without cracks, holes, ridges, loose material and the like. - Defective areas: Remove and recompact to full thickness of layer using new material. 540 BENCHING IN FILL - Adjacent areas: If, during filling the difference in level between adjacent areas of filling exceeds 600 mm, cut into edge of higher filling to form benches 600 mm minimum width and height equivalent to depth of a layer of compacted filling. - New filling: Spread and compact to ensure maximum continuity with previous filling. 615 LOOSE TIP FILLING FOR LANDSCAPE AREAS - Filling: Do not firm, consolidate or compact when laying. Tip and grade to approximate levels in one operation with minimum of trafficking by plant. 618 HIGHWAYS AGENCY TYPE 2 UNBOUND MIXTURE - Fill: To Highways Agency Specification for highway works, clauses 801 and 804: - Crushed rock (other than argillaceous rock). - Crushed concrete. - Crushed non-expansive slag. - Well-burned non-plastic colliery shale. - Natural gravel. - Natural sand. - Filling: To Highways Agency Specification for highway works, clause and PROTECTION OF COMPACTED FILLING - Temporary protective filling: Before allowing construction traffic, raise level of compacted cohesive soil filling at least 150 mm above formation level using properly compacted temporary filling. - Removal: Remove temporary protective filling from site before permanent construction. 700 BACKFILLING AROUND FOUNDATIONS - Under oversite concrete and pavings: Hardcore as clause Under grassed or soil areas: Material excavated from the trench, laid and compacted in 300 mm maximum layers. 730 BLINDING - Surfaces to receive sheet overlays or concrete: - Blind with: - Concrete where shown on drawings; or - Sand, fine gravel, or other approved fine material applied to fill interstices. Moisten as necessary before final rolling to provide a flat, closed, smooth surface. - Sand for blinding: To BS EN 12620, grade 0/4 or 0/2 (MP). - Permissible deviations on surface level: mm.

7 5 D40 PILING To be read with Preliminaries/ General conditions and in conjunction with the Stage Design Statement by BP. GENERAL 110 PILING SPECIFICATION - Standard: Comply with the current edition of Specification for piling and embedded retaining walls (SPERW). - References to Engineer in SPERW: For the purpose of this contract, interpret such references as being to the person named in section A10 as administering the contract on behalf of the Employer. - Design working life category: 4 (50 years) 130 PILES - Standard: To SPERW, sections B2 B6, as appropriate to the pile type. - Permitted types: Any type of rotary bored pile. - Project specification: Submit proposals to cover the SPERW requirements in clause B1.2 and listed under this heading for the chosen pile type. - Other requirements: Limited headroom piling required beneath overhanging tree as noted on the drawings. 170 BORED CAST-IN-PLACE PILES - Standard: To SPERW, section B3. - Filling material: Reinforced concrete. - Pile group designation: All internal piles. - Diameter: Contractor choice. - Length: Contractor choice. - Reinforcement: Quantity: Contractor choice. Extent: As required by pile design - Other requirements: None. SYSTEM PERFORMANCE 210 CONTRACTOR DESIGN - Standard: To BS8004, BS Design responsibility: - Piles: Complete design in accordance with SPERW, clause B1.4, option 2. - Other: None. - Pile layout: Refer to drawings. - Site investigation: Confirm as adequate or propose further investigations as considered necessary. - Performance criteria for piles: As Clause Other requirements: None. - Submission of information: As required by SPERW, table B1.1 and elsewhere, as appropriate for the pile type, materials and tests specified. - Amendments to requirements specified in SPERW for information required: Prior to commencing the works: Submit proposals for working close to the façade and proposals for monitoring ground movements. Submit calculations illustrating predicted wall movements and demonstrating compliance with Clause 285 of this specification. Submit proposals for limited headroom piling. 230 GROUND INVESTIGATION - Report: Prepared by Chelmer Site investigations Ltd, available. - Datum for borehole logs: As site investigation report. - Obstructions/ voids: As described in site investigation report.

8 6 250 PERFORMANCE CRITERIA FOR STRUCTURE TO BE SUPPORTED ON THE PILES - Permitted settlement at working load (maximum): 20mm 260 SPECIFIED WORKING LOADS FOR PILES - Design factor of safety (minimum): 3. - Pile group designation: All. - Load magnitude: Refer to drawings. 285 DAMAGE TO ADJACENT STRUCTURES AND SERVICES - Permissible damage criteria: - Structures: No worse than CIRIA C580 Table 2.5 Category 2. - Services: No damage permitted. 290 BASIS FOR SETTING OUT - Site datum: Refer to drawings. - Site grid: Refer to drawings. 300 COMMENCING SURFACE - Level: Refer to drawings. 320 PILE LENGTH TOE LEVEL - Pile group designation: All. - Pile cut-off level: Refer to drawings. - Depth of pile toe beneath site datum (minimum): As required by design. - Other requirements: None. 345 INSTALLATION TOLERANCES FOR PLUNGED COLUMNS - Pile tolerances: - Setting out at ground level: + / - 25mm - Verticality: 1:200 - Column tolerances: - Setting out at ground level: + / - 10mm - Centrality on pile head: + / - 50mm. - Verticality: 1:600 target, 1:300 max. - Level of head: + / - 25mm - Rotational: + / - 15 deg. - Method of achieving tolerances: Submit proposals. PRODUCTS 440 PERMANENT CASING - Submit proposals. 445 SLEEVES - Submit proposals. 450 COATING of plunged columns not required. 470 CONCRETE GENERALLY - Standards: To BS and SPERW, section B19. - Project compressive strength testing of concrete: One sample taken from each of the first three piles and thereafter one sample from every 5 th pile. - Exchange of information: Provide concrete producer with information required by BS , clauses 4 and 5.

9 7 480 DESIGNED CONCRETE BY PILING CONTRACTOR - Embedded metal: Carbon steel reinforcement and structural steel. - Compression strength class (cylinder/ cube minimum): C32/40 - Target density (oven-dry): Normal. - Fibres: Not required. - Aggregates: - Size (maximum): 20mm - Type/ Density: Normal weight. - Coarse recycled aggregates: Not permitted. - Additional aggregate requirements: None. - Design chemical class: DC-4 (FND4) - Limiting values for composition: - Water:cement ratio (maximum): Contractor s choice - Cement/ Combination content (minimum): Contractor s choice - Cement/ Combination content (maximum): Contractor s choice - Air content in situ (minimum): Contractor s choice - Consistence class: Contractor s choice - Permitted cement/ combinations: Contractor s choice. - Chloride class: CI Admixtures: Submit proposals. - Additional requirements: None. 530 REINFORCEMENT GENERALLY - Steel reinforcement: To BS Type/ Strength grade: Ribbed bar, Grade 500B - Supplier: Firm holding a valid certificate of approval issued under a product certification scheme operated by a third party certification body with appropriate Category 2 accreditation from the United Kingdom Accreditation Service (UKAS). - Other requirements: None. 540 COVER TO REINFORCEMENT - Cover (nominal): 75mm - Method of ensuring correct cover: Submit details. 550 LAPS IN REINFORCEMENT - Length (minimum): 40 x bar diameter. - Type:. 580 PLUNGE COLUMNS - Material: Grade S355J0. - Fabrication: To National Structural Steelwork Specification. - Protective coating: Not required. EXECUTION 610 METHOD STATEMENT - Requirement: Submit proposed method of installation to achieve the design parameters, including: - Details of equipment. - Programme showing sequence and resources. - Confirmation that performance requirements for load and settlement will be achieved. 615 RECORDS AND SUBMISSION OF INFORMATION DURING THE WORKS - Generally: As required in SPERW, tables B1.1, B1.6 and elsewhere, as appropriate for the pile types, materials and tests specified. - Amendments to requirements: None.

10 8 620 WELDING PROCEDURE - Requirements additional to SPERW, section B6: None. 625 NON-DESTRUCTIVE TESTING OF WELDS - Requirements: To SPERW, clause B Erratum: Substitute BS EN ISO 5817 for BS EN Additional requirements: None. - Exceptions to requirements of BS EN 12063, table 1: None. 650 PERFORMANCE OF WORKING PILES - Substandard performance: Give notice if the performance of any pile will be less than that of a similar pile whose test behaviour has been accepted. 675 SUPPORT FLUID - Standard: To SPERW, section B18. - Usage: Submit proposals. - Permitted fluids: Bentonite - Loss of fluid: Submit proposals. - Additional requirements: None. 685 EXCAVATED MATERIAL - Disposal: To be removed from site by Piling Contractor. 690 DISPOSAL OF PILE HEADS - Cutting down and disposal: Contractor s responsibility. 696 METHOD OF PLACING PILE FILLING - Designation: All. - Requirement: Submit proposals. 700 PLACING FILLING IN DRY BORINGS AND CASINGS - Requirements additional to SPERW, clause B : - Height of lower end of delivery tube above bottom of reinforcement cage (maximum): Submit proposals. - Free fall of concrete (maximum): Submit proposals. 702 INSTALLATION OF PLUNGE COLUMNS - Survey: On completion of borehole, survey location and verticality of hole. Report if plunge column tolerances will be difficult to achieve and submit proposals. - Placing: Place pile concrete and while concrete is still fluid insert column. Check location and verticality of column before concrete sets. - Backfill: When concrete has set, backfill voids around column with Sand. - Protect: Column from impact and movement due to ground heave during bulk excavation. 750 TESTING SUPPORT FLUID - Submit proposals. 755 PREPARATION OF PILE HEADS FOR INTEGRITY TESTING - Preparation: To suit test method. - Inconsistencies: Submit report on inconsistencies which could inhibit execution or interpretation of test. 760 PILE INTEGRITY TESTING GENERAL - Method: Submit proposals - Satisfactory evidence in support of proposals: Submit. - Period between casting and testing (minimum): 7 days.

11 9 - Piles to be tested: - Pile group designation: All. - Number of piles to be tested: 20% - Locations: To be agreed on site - Programme: To be agreed on site - Other requirements: None. COMPLETION 910 HEALTH AND SAFETY FILE - Piling completion report: Collate and submit a full set of pile records for inclusion in the health and safety file. - Content and date for submission: As SPERW, clause B Record plan: Give the number of each pile and its final location relative to nearest grid. - Additional requirements: None. 920 PILING GUARANTEE - Type: Insurance backed. Administered by an independent insurance protection company. - Guarantee period (minimum): 12 years - Documentation: Provide certificates/ guarantees at completion of piling works.

12 10 D40 EMBEDDED RETAINING WALLS To be read with Preliminaries/ General conditions and in conjunction with the Stage Design Statement by BP. GENERAL 110 EMBEDDED RETAINING WALL SPECIFICATION - Standard: Comply with the current edition of Specification for piling and embedded retaining walls (SPERW) except where specified otherwise. - Substitution of British Standards for SPERW requirements: None. - References to the Engineer in SPERW: For the purpose of this contract, interpret such references as being to the person named in section A10 as administering the contract on behalf of the Employer. 130 EMBEDDED RETAINING WALL - Permitted types: assumed to be contiguous continuous flight augured piles but final design to contractor s proposals. - Particular: specification: Submit proposals to cover the SPERW requirements listed under this heading for chosen wall type. - Other requirements: Consider site access constraints discussed in the Stage Design Statement by BP. 175 CONTIGUOUS BORED PILE WALLS - SPERW, sections: 4, 15 and Piles: Currently assumed to be continuous flight augured piles. - Diameter (minimum): 450 and 350mm but to be confirmed by contractor s design proposals. - Spacing (maximum): Submit proposals. - Guide walls: Contractor s choice. - Tolerance on concrete protrusions:. - Requirements for tolerance in addition to SPERW: refer to BP drawings. SYSTEM PERFORMANCE 210 CONTRACTOR DESIGN - Standards to be used for design: To BS 8002, BS 8004, BS Requirement: Complete the design of embedded retaining walls and construct in accordance with SPERW, clause 11.4, option 1. - Construction: Assumed single level of propping (contractor to submit proposals). - Sequence: Assumed Top Down construction. - Embedded retaining wall layout: Refer to BP drawings. - Water resistance: Perimeter pilled wall to prevent water ingress to a manageable level during construction process only and without damage to adjacent properties. - Special requirements: Grout between piles to prevent water ingress as necessary (refer to clause 240). Design piles for a water level of 1m below existing ground level as required by BS Design life of retaining wall to be 50 years. - Site investigation: Confirm as adequate or propose further investigation as considered necessary. 225 INFORMATION TO BE PROVIDED BEFORE COMMENCING DETAILED DESIGN OF EMBEDDED RETAINING WALLS - Submittals: reports and calculations demonstrating compliance with the specification. - Confirmation of water levels and adequacy of piling system to deal with water level. - Reinforcement proposals. 227 INFORMATION TO BE PROVIDED BEFORE COMMENCING CONSTRUCTION OF EMBEDDED RETAINING WALLS - Submittals: - Information listed in SPERW, table Additional information:

13 11 - Details of piling sequence. - Confirmation that the installation of the embedded retaining wall will not damage Adjacent structures/services. - Details of size and weight and plant to be used. - Details of the method of transporting and placing concrete in the piles. - Proposals for working close to protection of adjacent facades. 230 GROUND INVESTIGATION - Report: Prepared by Chelmer Site investigations Ltd, available. - Datum for borehole logs: Refer to report. 240 ADDITIONAL GROUND INVESTIGATION - Information required: Ground water level to monitored regularly from start of contract. - Extent of investigation: - Location: Existing standpipe. - Frequency of sampling/ testing: Twice weekly. 265 LOADS ON WALLS AND EXCAVATION DEPTHS - Standards: To BS , 2 and 3 and BS Characteristic vertical loads: Refer to BP drawing 4925/100 - Retention loads: Calculate taking into account the following: - Soil representative strength parameters: As assessed from site investigation report. - Design ground water level: 1.0m below adjacent ground water level. - Over excavation to be assumed in front of wall: 10% as BS 8002 cl Uniform surcharge loading on surface of retained soil: 10kN/m² - Additional surcharge loading: Refer to BP drawings. - Excavation depths: Refer to BP drawings. 267 LIMITS ON GROUND MOVEMENT DURING CONSTRUCTION - Movement of survey points must not exceed: - Settlement: Action values: 10mm. Trigger values: 6mm - Lateral displacement: Action values: 10mm. Trigger values: 6mm. - Movement approaching critical values: - Trigger: Submit proposals for ensuring action values are not exceeded. - Action: Stop work. 285 DAMAGE TO ADJACENT STRUCTURES AND SERVICES - Permissible damage criteria: - Structures: None. - Services: None. 290 BASIS FOR SETTING OUT - Site datum: Ordnance (Newlyn) datum. - Site grid: To be confirmed on Architect s drawings. 300 COMMENCING SURFACE - Assumed piling platform level shown on BP drawing but contractor to submit proposals. 320 WALL TOE LEVEL - Panel: All. - Cut-off level: Pile to terminate within capping beam or slab.

14 12 - Depth of wall toe beneath site datum (minimum): To contractor s design assumed pile lengths are shown on BP drawings but are indicative only. - Other requirements: None. 350 WATER RESTRICTING CONSTRUCTION - Proposals to be submitted by contractor. PRODUCTS 433 CAST IN PLACE PILES ALL - Fill material: Prescribed concrete. - Placing: Contractor to submit proposals as part of their method statement. - Reinforcement: To contractor s design but no less that 6T16. - Extent: For the full length of the pile projecting 600mm minimum above pile cut Off level. - Other requirements: None 470 CONCRETE GENERALLY - Standard: To BS and SPERW, section B19. - Project compressive strength testing of concrete:. - Exchange of information: Provide concrete producer with information required by BS , clauses 4 and DESIGNED CONCRETE BY PILING CONTRACTOR - Embedded metal: Carbon steel reinforcement and structural steel. - Compression strength class (cylinder/ cube minimum): C32/40 - Target density (oven-dry): Normal. - Fibres: Not required. - Aggregates: - Size (maximum): 20 mm. - Type/ Density: Normal weight. - Coarse recycled aggregates: Not permitted. - Additional aggregate requirements: None. - Design chemical class: DC-4 (FND4) - Limiting values for composition: - Water:cement ratio (maximum): Contractor s choice. - Cement/ Combination content (minimum): Contractor s choice - Cement/ Combination content (maximum): Contractor s choice. - Air content in situ (minimum): Contractor s choice. - Consistence class: Contractor s choice. - Permitted cement/ combinations: Contractor s choice. - Chloride class: CI Admixtures: Submit proposals. - Additional requirements: None. 530 REINFORCEMENT GENERALLY - Steel reinforcement: To BS Type/ Strength grade: B500B - Cutting and bending: To BS Supplier: Firm holding a valid certificate of approval issued under a product certification scheme operated by a third party certification body with appropriate Category 2 accreditation from the United Kingdom Accreditation Service (UKAS). - Lap length (minimum): 40 x bar diameter.

15 13 EXECUTION 610 METHOD STATEMENT - Requirement: Submit proposed method of installation to achieve the design parameters including: - Details of equipment. - Programme showing sequence and resources. - Confirmation that performance requirements for load and settlement will be achieved. - Proximity of piling to site boundary to achieve maximum basement wall offsets as detailed on BP drawings. 615 RECORDS - Detailed requirements for records additional to those specified in SPERW: None. 655 TESTING EXCAVATED MATERIAL - Contamination tests: Undertake at following rates: - Made up ground: Submit proposals. - Other soil types: Submit proposals. 680 PROHIBITION OF SUPPORT FLUID - Usage: Not permitted. 685 EXCAVATED MATERIAL - Disposal: Contractor s responsibility. 703 COVER TO REINFORCEMENT - Cover (nominal): Submit proposals. - Method of ensuring correct cover: Submit proposals 705 MONITORING GENERALLY - Ground conditions: Observe soil and groundwater levels. - Conditions that are not in accordance with design data, including unforeseen obstructions: Report. - Ground movements: Establish measuring points in the locations and at the depths Submit proposals. - Refer to Stage Statement by BP. 740 COMPRESSIVE STRENGTH TESTING OF CONCRETE - Requirement: In addition to any sampling and testing carried out by the concrete supplier, and unless otherwise agreed, sample concrete on site and test. - Sampling rate: As SPERW section PREPARATION OF PILE HEADS FOR INTEGRITY TESTING - Preparation: To suit test method. - Inconsistencies which could inhibit execution or interpretation of test: Submit report. 760 INTEGRITY TESTING FOR CONTIGUOUS BORED PILE WALLS - Method: Contractor s choice. - Satisfactory evidence in support of proposals: Submit - Period between casting and testing (minimum): 7 days minimum and timing suit programme. - Piles/ walls to be tested: - Number: All. - Location: All. - Programme: Contractor s choice. 775 PERIODS FOR SUBMISSION OF INTERGRITY TEST RESULTS - Initial test results: Submit after each test within 24 hours. - Full report: Submit after completion of each phase of testing within 14 days.

16 14 COMPLETION 910 HEALTH AND SAFETY FILE - Walling completion report: Collate and submit a full set of records for inclusion in the health and safety file. - Number of copies: Two. - Content: - Record drawings: With each wall element numbered and giving the as built location of each relative to nearest grid lines. - Records: Copy of each record submitted during the progress of the work. - Latest date for submission: Within 14 days of completing piling works. 920 PILING GUARANTEE - Type: Insurance backed. Administered by an independent insurance protection company. - Guarantee period (minimum): 12 years. - Documentation: Provide certificates/ guarantees at completion of piling works. - Concrete where shown on drawings (to specification E10/05)

17 15 D50 UNDERPINNING To be read with Preliminaries/ General conditions and in conjunction with the Stage Design Statement by BP. GENERAL 115 UNDERPINNING DESIGN MASS CONCRETE UNDERPIN TO PARTY WALL - Purpose: To enable construction of capping beam at lower ground level SSL. - Extent: Refer to BP drawings - Standards: Mass concrete underpinning to BS Requirement: - Working Loads: Not applicable. - Load factor: Not applicable. - Assumed bearing strata: London Clay. - Design proposals: Confirm as adequate for the particular ground conditions revealed in the works or submit alternatives. 115 UNDERPINNING DESIGN RC UNDERPIN TO PERIMETER WALLS (ELEVATIONS AND GABLE) - Purpose: To enable construction of capping beam at lower ground level SSL. - Extent: Refer to BP drawings - Standards: concrete underpinning to BS Requirement: - Working Loads: Not applicable. - Load factor: Not applicable. - Assumed bearing strata: London Clay. - Design proposals: Confirm as adequate for the particular ground conditions revealed in the works or submit alternatives. 155 GROUND INVESTIGATION - Report: Chelmer SI Report available 170 DISCONNECTION OF SERVICES IN WORKING AREAS - Disconnections required: Refer to specification C20 and specification by M&E Consultant. - Timing: Before commencing underpinning works within the building. - Reconnection: Ensure that services cannot be reinstated by site operatives without consent. TYPES OF UNDERPINNING 210 CONTINUOUS MASS CONCRETE UNDERPINNING - Underpinning blocks: - Depth: Nominal 1 metre. - Length (maximum): 1 metre. - Width on either side of wall centre line (minimum): 300mm. - Depth of hard pack: mm. - Materials: - Concrete: See specification E10/105 - Hard packing: 1:3 cement: sharp sand mortar. Water content: Sufficient only to ensure that packing binds together. - Sequence: Submit proposals but no more than 25% of wall length to be unsupported at any time. Proposals to be submitted 28 days before commencement on site to enable agreement with Party Wall surveyor. - Curing periods (minimum):

18 16 - Between casting underpinning block and pinning up: 24 hours - Between completion of pinning up and commencement of excavation for the next sequence of underpinning: 24 hours Extend curing periods to allow for inclement weather. - Shear connection between underpinning blocks: joggle joints between adjacent stools. - Features: underpin not to project further into site than existing footing. 211 CONTINUOUS RC UNDERPINNING TO PERIMETER WALLS - Underpinning blocks: - Depth: Nominal 1 metre. - Length (maximum): 1 metre. - Width on either side of wall centre line (minimum): 300mm. - Depth of hard pack: mm. - Materials: - Concrete: See specification E10/106 - Hard packing: 1:3 cement: sharp sand mortar. Water content: Sufficient only to ensure that packing binds together. - Sequence: Submit proposals but no more than 25% of wall length to be unsupported at any time. Proposals to be submitted 28 days before commencement on site to enable agreement with Party Wall surveyor. - Curing periods (minimum): - Between casting underpinning block and pinning up: 24 hours - Between completion of pinning up and commencement of excavation for the next sequence of underpinning: 24 hours Extend curing periods to allow for inclement weather. - Shear connection between underpinning blocks: joggle joints between adjacent stools. - Features: underpin not to project further into site than existing footing. ACCESSORIES FOR UNDERPINNING 435 IN SITU CONCRETE FOR UNDERPINNING - Standard: To BS Concrete: designed as specification E10/105 and Embedded metal: None. - Fibres: None. - Immature concrete: Protect from drying, frost and loading for a minimum period of 7 days. - Extend period to allow for inclement weather. - Cover to reinforcement (minimum): - Top face: not applicable. - Faces cast against not applicable. 440 MAKING CONCRETE GENERALLY - Standard: To BS Exchange of information: Provide concrete producer with information required by BS , clauses 4 and ADDITIONAL REQUIREMENT FOR CONCRETE QUALITY - Variation from BS : Comply with the requirements of BRE special Digest 1 where these vary from those of BS STEEL REINFORCEMENT GENERALLY

19 17 - Type/ Strength grade: Cutting and bending: To BS Lap lengths (minimum): 40 x bar diameter. - Supplier: Firm holding a valid certificate of approval issued under a product certification scheme operated by a third party certification body with appropriate Category 2 accreditation from the United Kingdom Accreditation Service (UKAS). - Cleanliness: At time of placing concrete, reinforcement to be clean, free of corrosive pitting and loose millscale or rust. EXECUTION 610 LOOSE MASONRY/CONCRETE - Specification: test underside of existing masonry/footing for soundness by tapping with a hammer. Break out and remove any loose or unsound material to a uniform level soffit. 615 CONSTRUCTION OF MASS CONCRETE UNDERPINNING - Block and working space: Excavate together. - Formation: - Preparation: Remove or compact loose material. - Protection: Cover with 50 mm thickness of concrete if there will be a delay of more than four hours between completion of excavation and casting of concrete underpinning. - Keep excavations clean and dry. Remove all soil and loose concrete from adjacent completed pins to for a good key. - Do not excavate beyond the required width of footing at the rear. Do not excavate more working space than necessary at the front. - Split sleeves: Provide around drain/ service passing through underpinning. Closely fit a rigid sheet to each side of opening to prevent ingress of fill or vermin. - Clearance around drain/ service (minimum): 50mm. - Dowels/ Shear key/ Front shutter: Plain vertical formwork for the inner face of the underpinning with joints sealed to prevent water loss. Provide shear key via joggled joints. - Casting underpinning: In one lift, leaving a gap for packing up beneath existing foundation. - Packing: On completion of concrete curing period, hard pack gap between underpinning block and existing foundation. Pack in strips not exceeding 75mm. Allow packing to cure before commencing excavation for the next sequence of underpinning. COMPLETION 910 HEALTH AND SAFETY FILE - CONCRETE UNDERPINNING - Requirement: Collate and submit a full set of records for inclusion in the health and safety file. - Number of copies: two. - Content: For each underpinning block record: - Date of casting. - Depth of base below datum. - Length. - Width either side of wall. - Details of drains and services built into block and diameter of sleeving. - Latest date for submission: 14 days after completion.

20 18 E05 IN SITU CONCRETE CONSTRUCTION GENERALLY To be read with Preliminaries/ General conditions and in conjunction with the Tender Stage Design Statement by BP and design and Performance Specification for Detailing and Scheduling of Reinforced Concrete Elements. 215 CONTRACTOR DETAILING OF REINFORCEMENT - Extent: All in situ reinforced concrete structure shown on BP drawings. - Requirement: Complete the detailing and scheduling of reinforcement. - Standards: - Design: To BS & liaison with Pudlo/Cementaid required. - Drawings: BS EN ISO 3766 & refer to BP performance specification. - Reinforcement schedules: To BS Design information: - Designed reinforcement: Format to design information to be agreed with contractor also refer to BP performance specification. - Additional reinforcement: Control of cracking: Provide additional reinforcement and adjust spacing of reinforcement as design standard requirements for the control of cracking. Other: None. - Reinforcement: - Order of priority when clashes occur: Raise query with BP. - Other detailing requirements: None. - Finished product: To comply with the requirements of design standard. 225 TEMPERATURE RECORDS - Requirement: Throughout period of concrete construction record: - Daily: temperature intervals at four hours. - Under adverse temperature conditions: Temperature at commencement and end of placing. - Equipment: Contractor s choice. - Location: In the shade, close to the structure. 235 OPENINGS, INSERTS AND FIXINGS - Requirement: Collate all information. - Submit: Details where openings, inserts and fixings can only be accommodated by adjustments to reinforcement. - Locate reinforcement: To ensure specified minimum cover at openings and inserts and to be clear of fixing positions. 290 ACCURACY OF CONSTRUCTION - Setting out: To BS Element shape and position: The national Structural Concrete Specification for Building Construction. - Substitution of alternative requirements: None. 300 LEVELS OF STRUCTURAL CONCRETE FLOORS - Tolerances (maximum): - Level of floor: +/- 20mm. - Steps in floor level: +/- 5mm. 310 SURFACE REGULARITY OF CONCRETE FLOORS TO BS GENERAL - Standard: To BS or Measurement: From underside of a 2 m straightedge (between points of contact) placed anywhere on surface and using a slip gauge. 315 SURFACE REGULARITY OF CONCRETE FLOORS TO BS TOLERANCE CLASS SR3 - Location: Basement slab - Abrupt changes: 10mm.

21 SURFACE REGULARITY OF CONCRETE FLOORS TO BS TOLERANCE CLASS SR2 - Location: All slabs above basement level. - Abrupt changes: 5mm. 430 SURFACE CRACKING GENERALLY - Method of measurement: To be proposed by contractor. - Critical crack width: 0.3mm. - Action: Should cracks occur that are wider than the critical crack width: - Survey: Frequency and extent of such cracks and investigate cause. - Report: Findings together with recommendations for rectification.

22 20 E10 MIXING/ CASTING/ CURING IN SITU CONCRETE To be read with Preliminaries/ General conditions and in conjunction with the Tender Stage Design Statement by BP. CONCRETE 101 SPECIFICATION - Concrete generally: To BS EN and BS Other requirements: for concrete in the ground, requirements for concrete quality in special digest 1:2005 take precedence over those in BS Exchange of information: Provide concrete producer with information required by BS , clauses 4 and DESIGNATED CONCRETE FOR BLINDING, MASS CONCRETE FILL & MASS CONCRETE UNDERPINNING. - Designated concrete: GEN3. - Reinforcement / embedded metal: No. - Aggregates: - Size (maximum): 20mm. - Coarse recycled aggregates: RCA Permitted. - Additional aggregate requirements: None. - Consistence class: S3. - Chloride class: Admixtures: None. - Additional mix requirements: None. 106 DESIGNATED CONCRETE FOR ALL RC UNDERPINNING AND RETAINNING WALLS. - Designated concrete: RC32/40 - Reinforcement / embedded metal: YES. - Aggregates: - Size (maximum): 20mm. - Other requirements for admixtures: An accelerator or retarder may be used. 107 DESIGNATED CONCRETE FOR ALL SLABS AND WALLS/COLUMNS NOT IN CONTACT WITH GROUND PILES - Designated concrete: RC32/40 - Reinforcement / embedded metal: YES. - Aggregates: - Size (maximum): 20mm. - Other requirements for admixtures: An accelerator or retarder may be used. 125 SUBSTITUTION OF STANDARDIZED PRESCRIBED CONCRETE FOR DESIGNATED CONCRETE - General: Conform to BS , clause 8. - Substitution: In accordance with BS , table A Proposals: Submit for each substitution, stating reasons. - Site mixing: If standardized prescribed concretes are made on site conform to BS , subsections 2, 3 and DESIGNED CONCRETE FOR BASEMENT SUBSTRUCTURE CONCRETE WITH WATERPROOF ADDITIVE - Reinforcement / Embedded metal: Yes. - Compressive strength class (cylinder/ cube minimum): C40/50. - Target density (oven-dry): Normal - Aggregates: - Size (maximum): 20mm - Type/ Density: Normal weight.

23 21 - Coarse recycled aggregates: RCA Permitted subject to acceptance by the waterproof additive manufacturer (see below) - Additional aggregate requirements: None. - Design chemical class: AC-1. - Limiting values for composition: - Water/cement ratio (maximum): Cement/ combination content (minimum): In accordance with the waterproof additive manufacturer s requirements. - Cement/ combination content (maximum): In accordance with the waterproof additive manufacturer s requirements. - Air content in situ (minimum): No requirement. - Consistence class: Contractor s choice / In accordance with the waterproof additive manufacturer s requirements. - Permitted cement/ combinations: II subject to waterproof additive manufacturer s requirements. - Chloride class: Admixtures: Waterproof additive by Pudlo/Cementaid or similar approved; other admixtures permitted subject to selected waterproof additive manufacturer s approval. - Colour: Not required. - Additional mix requirements: None. MATERIALS, BATCHING AND MIXING 215 READY-MIXED CONCRETE - Production plant: Currently certified by a body accredited by UKAS to BS EN for product conformity certification of ready-mixed concrete. - Source of ready-mixed concrete: Obtain from one source if possible. Otherwise, submit proposals. - Name and address of depot: Submit before any concrete is delivered. - Delivery notes: Retain for inspection. - Declarations of nonconformity from concrete producer: Notify immediately. 218 SITE MIXED CONCRETE - Batching by mass: - Restrictions: Limit to mass concrete underpin, mass fill & blinding. - Accuracy of measuring devices: To BS EN 206-1, clause Tolerances for quantity of constituent material: To BS EN 206-1, table Batching by volume: - Restrictions: None. - Mixing: To BS , subsections 2, 3 and INFORMATION ABOUT PROPOSED CONCRETES - Submit when requested: - Details listed in BS , clause Additional information: None. 225 CHANGES TO SPECIFICATION - Changes to specification of fresh concrete (outside concrete producer's responsibility): Prohibited. 230 INTERRUPTION OF SUPPLY DURING CONCRETING - Elements without joints: Where elements are detailed to be cast in a single pour without joints, make prior arrangements for a back-up supply of concrete. - Elsewhere: - Preparation: Manage pour to have a full face, and have materials available to form an emergency construction joint while concrete can still be worked. - Before pour is completed: Submit location and details of joint, make proposals for joint preparation.

24 RECYCLED AGGREGATE - Standard: To BS , clause Type: Submit proposals. - Source: Submit proposals. 415 ADMIXTURES - Calcium chloride and admixtures containing calcium chloride: Do not use. 418 PROPRIETARY ADMIXTURE - Type: Superplaster SR and Everdue Caltite. - Manufacturer: Cementaid. - Special requirements: To be used strictly in accordance with manufacturer s instructions. 490 PROPERTIES OF FRESH CONCRETE - Adjustments to suit construction process: Determine with concrete producer. Maintain conformity to the specification. PROJECT TESTING/ CERTIFICATION 505 PROJECT TESTING OF CONCRETE - Purpose: No tests required for designated concrete but compressive strength testing is required for designed and prescribed mixes - Testing: To BS EN 206-1, Annex B and BS , Annex B. - Nonconformity: Obtain instructions immediately. - Recording: Maintain complete correlated records including: - Concrete designation. - Sampling, site tests, and identification numbers of specimens tested in the laboratory. - Location of the parts of the structure represented by each sample. - Location in the structure of the batch from which each sample is taken. - Tests: - Sampling: One sample per 20m³. 508 REGULAR PROJECT TESTING - Tests: Compressive strength. - Sampling: - Point: At point of placing. - Rate: one sample per 20m³. - Other requirements: None. 520 TESTING LABORATORY - Laboratory: Accredited by UKAS or other national equivalent. - Name and UKAS reference number: Submit well in advance of making trial mixes or concrete for use in the works. 530 TESTS RESULTS - Submission of reports: Within one day of completion of each test. - Number of copies: one. - Reports on site: A complete set, available for inspection. 550 BROKEN CUBES FROM FAILED STRENGTH TESTS - Nonconformity: Keep separately the pieces of each cube which fail to meet the conformity requirements for individual results. - Period for keeping cubes: Obtain instructions.

25 23 PLACING/ COMPACTING/ CURING AND PROTECTING 610 CONSTRUCTION/ SEQUENCE/ TIMING REQUIREMENTS - Maximum pour sizes to be in accordance with Cementaid requirements. - Contractor to submit sequence proposals as part of their method statement. 620 TEMPERATURE OF CONCRETE - Application: basement raft slab. - Objective: Limit maximum temperature of concrete to minimize cracking during placing, compaction and curing. Take account of: - High temperatures and steep temperature gradients: Prevent build-up during first 24 hours after casting. Prevent coincidence of maximum heat gain from cement hydration with high air temperature and/ or solar gain. - Rapid changes in temperature: Prevent during the first seven days after casting. - Proposals for meeting objective: Submit. 630 PREMATURE WATER LOSS - Requirement: Prevent water loss from concrete laid on absorbent substrates. - Underlay: Select from: Polyethylene sheet: 250 micrometres thick. Building paper: To BS 1521, grade B1F. - Installation: Lap edges 150 mm. - Refer also to requirements by Cementaid Ltd for Caltite concrete surfaces. 640 CONSTRUCTION JOINTS - Location of joints: To be part of contractor s method statement. - Preparation of joint surfaces: Remove surface laitance and expose aggregate by lightly brushing and spraying. Joint surface to be clean and damp immediately before placing fresh concrete. 648 ADVERSE TEMPERATURE CONDITIONS - Requirement: Submit proposals for protecting concrete when predicted ambient temperatures indicate risk of concrete freezing or overheating. 650 SURFACES TO RECEIVE CONCRETE - Cleanliness of surfaces immediately before placing concrete: Clean with no debris, tying wire clippings, fastenings or free water. 660 INSPECTION OF SURFACES - Notice: Give notice to allow inspections of reinforcement and surfaces before each pour of concrete. - Period of notice: 24 hours. - Timing of inspections: When fixing of reinforcement is complete. 670 TRANSPORTING - General: Avoid contamination, segregation, loss of ingredients, excessive evaporation and loss of workability. Protect from heavy rain. - Entrained air: Anticipate effects of transport and placing methods in order to achieve specified air content. 680 PLACING - Records: Maintain for time, date and location of all pours. - Timing: Place as soon as practicable after mixing and while sufficiently plastic for full compaction.

26 24 - Temperature limitations for concrete: 30 C (maximum) and 5 C (minimum), unless otherwise specified. Do not place against frozen or frost covered surfaces. - Continuity of pours: Place in final position in one continuous operation up to construction joints. Avoid formation of cold joints. - Discharging concrete: Prevent uneven dispersal, segregation or loss of ingredients or any adverse effect on the formwork or formed finishes. - Thickness of layers: To suit methods of compaction and achieve efficient amalgamation during compaction. - Poker vibrators: Do not use to make concrete flow horizontally into position, except where necessary to achieve full compaction under void formers and cast-in accessories and at vertical joints. 690 COMPACTING - General: Fully compact concrete to full depth to remove entrapped air. Continue until air bubbles cease to appear on the top surface. - Areas for particular attention: Around reinforcement, under void formers, cast-in accessories, into corners of formwork and at joints. - Consecutive batches of concrete: Amalgamate without damaging adjacent partly hardened concrete. - Methods of compaction: To suit consistence class and use of concrete. 720 VIBRATORS - General: Maintain sufficient numbers and types of vibrator to suit pouring rate, consistency and location of concrete. - External vibrators: Obtain approval for use. 730 PLASTIC SETTLEMENT - Settlement cracking: Inspect fresh concrete closely and continuously wherever cracking is likely to occur, including the top of deep sections and at significant changes in the depth of concrete sections. - Timing: During the first few hours after placing and whilst concrete is still capable of being fluidized by the vibrator. - Removal of cracks: Revibrate concrete. 810 CURING GENERALLY - Requirement: Keep surface layers of concrete moist throughout curing period, including perimeters and abutments, by either restricting evaporation or continuously wetting surfaces of concrete. - Surfaces covered by formwork: Retain formwork in position and, where necessary to satisfy curing period, cover surfaces immediately after striking. - Top surfaces: Cover immediately after placing and compacting. If covering is removed for finishing operations, replace it immediately afterwards. - Surface temperature: Maintain above 5 C throughout the specified curing period or four days, whichever is longer. - Records: Maintain details of location and timing of casting of individual batches, removal of formwork and removal of coverings. Keep records on site, available for inspection. 811 COVERINGS FOR CURING - Sheet coverings: Suitable impervious material. - Curing compounds: Selection criteria: - Curing efficiency: Not less than 75% or for surfaces exposed to abrasion 90%. - Colouring: Fugitive dye. - Application to concrete exposed in the finished work: Readily removable without disfiguring the surface. - Application to concrete to receive bonded construction/ finish: No impediment to subsequent bonding. - Interim covering to top surfaces of concrete: Until surfaces are in a suitable state to receive coverings in direct contact, cover with impervious sheeting held clear of the surface and sealed against draughts at perimeters and junctions.