FIRST FLOOR, UNIT 6 UNION PARK PACKET BOAT LANE UXBRIDGE UB8 2GH TEL: 01895 430700 FAX: 01895 430550

Project 4208.6 Proposed Construction of a Single Storey Basement and Alterations at; 7 Thurloe Street, SW7 2SS Structural Design Philosophy S. R. MASTERS B.Sc.(Hons).,C.Eng.,M.I.Struct.E.,M.B.Eng. Sept 2014

Contents 1

1. INTRODUCTION TO MMP DESIGN 2. MMP DESIGN DIRECTORS 3. EVIDENCE OF COMPETENCE & RESOURCES

Details of Organisation Nature of Organisation Incident/Accident Record Membership of Professional Bodies Professional Indemnity/Liability Insurance Details of Persons to be Employed Familiarity with Construction Processes Awareness of Relevant Health & Safety and Fire Regulations Health & Safety Practices Management Systems Resources Technical Facilities to Support the Designer(s) Method of Communication Design Decisions Remaining Risks

4. THE SITE 5. PROPOSED DEVELOPMENT 6. EXISTING STRUCTURE 7. EXISTING FLOOR PLANS AND SECTIONS 8 SOIL CONDITIONS, FOUNDATIONS 9 WATER 10. HEAVE AND SETTLEMENT 11 SLOPE INSTABILITY 12 IMPACT ON DRAINAGE AND SURFACE WATER 13 EFFECTS ON ADJACENT STRUCTURES 14 DESIGN PRINCIPLES

Ground Floor Structure Concrete Basement Lightwell Ground Water

15. DESIGN CRITERIA

General Existing Brickwork Typical Underpinning Sequence Materials

16. PROPOSED FLOOR PLANS AND SECTIONS 17. DESIGNERS RISK ASSESSMENT

Excavations Suspended Floors Masonry Walls Steel Beams Hazards & Risks Which Cannot be Designed Out

18. SEQUENCE OF OPERATION

Contents 2 APPENDIX A – CONSTRUCTION DETAILS

Underpinning Plans and Sections Foundation Line Loads

APPENDIX B – DESIGN CALCULATIONS

Loading Soil and Water Pressure Stability Check Reinforcement Design

APPENDIX C – SITE INVESTIGATIONS Site Investigation Report APPENDIX D – CONSTRUCTION SPECIFICATIONS

Earthworks Excavation and Filling Underpinning of Existing Foundations Concrete and Reinforced Concrete Construction

INTRODUCTION TO MMP DESIGN MMP Design Limited was formed as a private limited company in 1988 by one of the current Directors. Since then it has developed into it's present form as a firm of consulting engineers with expertise in Structural and Civil Engineering Services. Within the Company experience has been gained in a range of projects from structural surveys through refurbishment to multi-million pound developments and the Directors have experience in residential, retail, commercial, community care and educational projects. The Company also has commitment to all types of work including Design and Construct projects. The Company philosophy is to provide the fullest and most cost effective service to Clients. The Directors have a direct involvement with each project taking on the day to day control in order to provide the best possible service and the experience of the principals in the construction processes ensures that the objectives of buildability and cost effectiveness are met. With regard to the Company’s association with retro-fit basements, we have been working within this field since 1999 and during that time have had a direct involvement in the design of more than 670 such schemes. MMP DESIGN DIRECTORS Steven R. Masters - BSc(Hons).,C.Eng.,M.I.Struct.E.,M.B.Eng. Philip Seastram - BSc(Hons). Andrew J. Stone - BSc(Hons).,C.Eng.,M.I.C.E.,M.I.H.T.,Eur.Ing.

EVIDENCE OF COMPETENCE & RESOURCES Details of Organisation Name: MMP Design Address: First Floor Unit 6

Union Park Packet Boat Lane Uxbridge UB8 2GH

Contact: S. R. Masters Nature of Organisation Consulting Civil, Structural and Highway Engineers Incident/Accident Record None recorded Membership of Professional Bodies S. R. Masters - BSc(Hons).,C.Eng.,M.I.Struct.E.,M.B.Eng. A. J. Stone - BSc(Hons).,C.Eng.,M.I.C.E.,M.I.H.T.,Eur.Ing. Professional Indemnity/Liability Insurance PI is in place to cover our duties under CDM with cover limited to £1,000,000 and the liability period limited to 6 years. Details are available upon request. Details of Persons to be Employed S. R. Masters & A. J. Stone – Chartered Engineers & Project Leaders P. Seastram – Project Leader & Designer M. Kruz – Designer N. King & S. Barrow – CAD Operators Familiarity with Construction Processes The Directors have extensive experience in underpinning and retro-fit basement construction and have been instrumental in the development of some of the working practices adopted by the leading basement constructors. Awareness of Relevant Health & Safety and Fire Regulations Within the Company we have documentation relating to these matters which are regularly updated and circulated among the Directors and members of staff. Health & Safety Practices A copy of the Company’s Health & Safety Policy is available upon request.

Management Systems A Project Director is responsible for the design and resourcing of the project. Generally projects are undertaken in house with occasional external draughting only where necessary. Communications are by way of verbal and/or written instructions. All work is checked before leaving the office. Resources The Company comprises three working Directors together with full time and part time technical assistance sufficient to meet the design requirements for this project. Technical Facilities to Support the Designer(s) SCALE Structural Design suite Staad/QSE Structural Analysis suite Members of BSI Members of TRADA Members of BRE Method of Communication Design Decisions Design decisions are communicated verbally and confirmed in writing or by drawing revisions. All drawings are issued to relevant parties as required by the Lead Consultant and/or the Client. Remaining Risks Remaining risks will be communicated in writing to the appropriate Authority.

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:ffi cranbrook Project: 7 Thurloe Street Basements

London SW72$

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:ffi cranbrook Project: 7 Thurloe Street Basements

London SW72$

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Existing First Floor Layout

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I Client: Mr & Mrs Bauer I m b k Cran roo Project: 7ThurloeStreet Basements

London SW72$

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THE SITE Thurloe Street is located to the south of the A4 Cromwell Road and to the north of South Kensington underground station. The site is on the north side of Thurloe Street and is essentially level. The property shares party walls with Nos. 9 and 5 Thurloe Street which are properties of similar age and general arrangement. No. 9 is to the left when viewed from the road. The footprint of the existing lower ground floor is approximately 5.5m wide between the site boundaries by 20.0m long between the external faces of the frontmost and rearmost walls. PROPOSED DEVELOPMENT It is proposed to construct a two storey basement beneath an existing (non original) rear extension,extending to approximately 7m below the existing lower ground floor level. Waterproofing of the basement will take the form of drained cavities with sumps and pumps within the basement area. The new drainage to the basement rooms will be pumped to the existing system.

EXISTING STRUCTURE The structure was built in the late 19th century and the mid-terrace property originally comprised four storeys beneath a tile covered pitched roof with a four storey stepped and flat roofed annexe to the rear. Subsequently the main pitched roof was replaced with a mansard type structure to create an additional floor and to the rear a two storey extension was added alongside the original annexe. The external and party walls are of solid masonry which likely extend down to a corbelled brick footing; the internal load bearing walls are also of masonry except at the uppermost floor levels where they are of timber studwork. The upper floors are of suspended timber throughout whilst the lower ground floor comprises a ground bearing concrete slab. The property is generally in it’s original structural form except where previously described and plans showing the existing floor layouts are attached. SOIL CONDITIONS & FOUNDATIONS A Site investigation was carried out by Chelmer Site Investigations on 7th June 2013 and their report reference CSI//FACT/3787 is attached. The ground conditions were found to comprise some made ground overlying medium dense gravelly course sand which was proved to 10.0m below the rear garden ground level. Although the san was moist, no significant ground water was encountered. In the absence of any laboratory testing we have looked to BS.8002, BS.8004 and the Reinforced Concrete Designers Handbook (by Charles E. Reynolds and James C. Steedman) for a suggested range of parameters to be adopted for the design. For the soil profile previously described the guidance suggests an Angle of Internal Friction of 30-45° and an allowable Net Bearing Pressure (with no addition for depth of embedment) of 100-300 kN/m2. Hence the following parameters will be adopted.

φ = 35° (so Ka = 0.271) and δ = 19 kN/m3 Allowable bearing stress at GL = 125 kN/m2 Allowable bearing at Basement Level 1 = 125 + soil removed, say = 175 kN/m2 Allowable bearing at Basement Level 2 = 175 + soil removed, say = 225 kN/m2 Allowable bearing at Basement Level 3 = 225 + soil removed, say = 275 kN/m2

These parameters have been confirmed by previous testing regimes carried out over a period of almost 15 years and are accepted by the checking authorities of no less than 13 London Boroughs. They represent the long term condition which when combined with the design being based on active earth pressures results in a much simplified but rather conservative approach. Should the conditions encountered during construction vary in any way from those described above then the design will be re-visited before any underpinning works are commenced. WATER Although no ground water was encountered during the ground exploration works, the porous nature of the sand is such that surface water can permeate and there is the possibility of an occasional build up against the new basement wall. It is for this reason that water will be assumed with the level being 0.75 x the retained depth or at 1m below GL, whichever is the worst condition.

HEAVE & SETTLEMENT The underpinning process involves transferring the foundation loads to a lower level and inevitably this leads to some settlement. Some movement will also be caused by the sequential transfer of load between different parts of the structure but the careful control of the underpinning process and sequence will keep such movements to a practicable minimum. Particular care will be taken in the vicinity of the more vulnerable parts of the existing fabric. The depth to the London Clay and the modest dimensions of the site are such that the heave of the lower lying Clay is unlikely to exceed a few millimetres or to have any discernible effect outside the site boundaries. Any movement that does occur will be further mitigated by the necessarily slow rate of the excavation and construction. At the lower level the basement floor slab will be used to resist these heave forces and by supporting the slab with the deeper underpinning and the internal column foundations, the resulting upward movement more or less counteracts the increased settlements expected due to the increased dig depth. SLOPE INSTABILITY The site is essentially level and therefore we confirm that in our opinion slope instability will not be initiated due to these works. IMPACT ON DRAINAGE AND SURFACE WATER We understand that there is no statutory drainage within the area of influence of the proposed basement works. With regard to surface water, the proposed basement is either below the existing building or is to have the garden reinstated above and so we do not foresee any significant impact on the surface water courses. It is commonly accepted that constructing a relatively small basement as proposed has little or no effect on the flow of local water in relation to adjoining properties. In fact even if mobile water was forced to find an alternative route as a consequence of the basement construction, any increase in the level of that water is likely to be significantly less than the natural variations associated with seasonal changes and rises in levels from extreme rainfall events. We concur with these views.

EFFECTS ON ADJACENT STRUCTURES Outside of the basement area the change of vertical stresses in the ground may result in limited upward movements but the operation may also cause some very minor settlements and horizontal movements towards the new basement. In addition the underpinning operations may cause localised settlements of the party walls only which might result in cracks forming at the junctions of the walls of the adjacent properties where they abut the party walls. It should be stressed however that any anticipated movements are expected to be minimal as they are generally suppressed by the stiffness of the structures above and those adjoining. It is our experience that the potential for damage will be limited to the party walls but this can be mitigated by appointing a suitably experience Contractor familiar with propping techniques and sequential operations and by the Designer giving the necessary consideration to the risk by specifying measures to ensure that significant damage is avoided. This would typically be in the form of transitional underpins where we consider the structure above to be particularly vulnerable but otherwise by ensuring that the foundation transitions occur at inherently strong intersections of the more robust load bearing walls. As a result we anticipate that should any damage occur it will be classified as Category 0 in the Category of Damage Chart, CIRIA C580. Category 0 is Negligible; hairline cracks of less than 0.1mm. However, there will always be some movement as it can never be completely avoided and there are occasions where unforeseen conditions beneath the property which were not or could not be detected by the pre-construction investigations will result in more extensive damage. From our experience of designing almost 600 retro-fit basement the chance of such an occurrence is less than 2% and even then the damage would be classified as Category 1 in the Category of Damage Chart. Category 1 is Very Slight, fine cracks less than 1mm that can be easily treated during normal decoration.

DESIGN PRINCIPLES Lower Ground Floor Structure Where the existing internal below ground floor level load bearing structure is to be removed, replacement will be by the use of steel and/or timber beams supported by the existing load bearing walls or new load bearing brick piers and/or steel posts. To ensure the continued stability of the structure without reliance from the adjoining properties, the existing and any new load bearing basement walls are strapped to the structural ground floor deck using 30mm x 5mm galvanised mild steel straps placed at 2m centres. New beams are not considered ‘restrained’ unless there is a mechanical connection to the top flange (or within 75mm of it). Hence timber floor joists do not restrain the compression flange unless they are notched into the web or nailed/screwed to a timber flange plate. In order to restrict any possible damage to the existing structure, the deflection in the new beams is restricted to 1/360th of the overall span, under the total characteristic load condition. Concrete The exact structural detail of any existing concrete ground bearing ground floor is also unknown although the thickness has been assumed as 200mm (plus 50mm finishes) and the non load bearing masonry walls will likely have been built off the slab. In such cases it will necessary to provide beams to support the slab; these will be spac ed at approximately 600mm centres hence several floor support beams will be designed to span up to various lengths and support at least 0.6m width of floor and new ceiling. All main beams will then be designed assuming the worst ground floor loading case. For DL of (0.60 x 6.00)+0.50 = 4.10 kN/m and IL of (0.60 x 1.50) = 0.90 kN/m, provide 152x152 UC.23 sections for spans up to 4.0m and 152x152 UC.30 sections for spans up to 4.5m. Basement The remaining load bearing structure will be underpinned in a traditional ‘hit and miss’ method to achieve the increased headroom required. The underpins comprise a vertical stem which is immediately beneath the existing wall and a base which usually has a toe and a nominal heel. The heel size is determined by ignoring the earth pressure and considering the maximum vertical load on the wall only, using this to find a minimum foundation width based on the soil bearing capacity. The toe of the base is then determined by considering the minimum vertical dead load on the wall along with the maximum pressure from the retained soil and with the wall assumed to be acting as a cantilever. In calculating the toe size, the maximum allowable bearing pressure is not exceeded and a minimum factor of safety against overturning of 2.5 is achieved. The toe and/or stem will only be reinforced when the underpin stem is subjected to tensile stresses due to the pressures from the retained material. This usually only occurs where the London Clays are present or where the retained depth of soil is large. To check the stresses in the underpin stem, the overturning moment taken about the basement slab is used. However, the design of the toe and the overall stability is based on the overturning moment taken about the underside of the underpin base. We assume the soil/stem interface to be friction free as ultimately this provides the most onerous design.

Basement Slab The new basement floor will be a 250mm thick reinforced concrete semi-suspended slab cast onto concrete blinding. In terms of potential ground heave the slab will span onto and connect to the perimeter underpins and any internal column foundations. Ground Water No significant ground water was encountered during the ground investigation works but if any local ground water is found during construction this water will be locally removed from the excavations by local pumping from the excavated area to a sump area. Water and moisture will generally be excluded from the permanent structure by the reinforced concrete walls/slab and the provision of an internal drained cavity system on the inside face of the walls/slab. Any water from the cavity system will drain to a sump in the external lightwell and be pumped into the house surface water drainage system. The concrete walls/slab will prevent the migration of large quantities of water or soil particles and therefore the drained cavity will only need to deal with a limited quantity of ground water. The upward water pressure on the basement will be resisted by the reinforced concrete basement slab tied into the concrete underpinning to the walls. There is sufficient weight in the loading to the underpinned walls and the basement structure to resist any ‘floatation’ effects.

DESIGN CRITERIA General The detailed structural design of the proposed works will be carried out in accordance with current British Standard Codes of Practice, Building Regulations and appropriate Guidance Documents published by CIRIA, ICE, IStructE etc. The design and drawings will be submitted to the local Building Control for approval and the construction inspected by the Building Inspector on site. Existing Brickwork Assuming 7N bricks in lime mortar, from CP.111 the basic compressive strength = 0.49 N/mm2 Hence under a concentrated load, bearing strength = 1.5 x 0.49, say 0.7 N/mm2 Typical Underpinning Sequence

6 1 4 7 2 5 8 3 6 1 4 7

Materials Concrete is grade C35 N/mm2 using Sulphate Resisting cement unless otherwise directed. Reinforcement is grade 500 N/mm2 Mortar is Class (iii).

Play Room

W.C En-suiteShowerRoom

Bedroom

Hallway Hallway UtilityRoom

Lightwell

Store

Lobby

Proposed Basement Floor Layout

Store/AV

Serv

ice

Voi

d

extent of frontsite boundary

protected stair may be required -subject to building control requirements

A A

A

Plant RoomServiceVoid

Proposed Lower Ground Floor Layout

extent ofbasementunder

A

T1

Extent ofIvy coveringto entiretrunkdiameter- 400mmmin

Rear Garden

T2

T1

boundary wall-7 Thurloe Street

400 400

63001600

8003900

Ivycoveringto entiretrunkdiameter- 400mmmin

boundary wall20 Thurloe Place

originalbuildingfootprint

originalbuildingfootprint

extent ofbasementunder

Originalfootprint oflisted building

T3

Wine Store

SCALE

0 5METRES

© THIS DRAWING IS THE COPYRIGHT OF CRANBROOK BASEMENTS. It shall not be in any way used or reproducedwithout their prior written consent. All dimensions are to be checked on site or in the workshop prior to commencing anywork. Work only to figured dimensions. Any discrepancies are to be reported to the Architect.

Client :

Project :

Drawing :

Scale :

Date :

Rev :

Dwg No :

No. Date Amendment Initials

Status :

Proposed Lower Ground & BasementFloor Layouts

1:100 @ A3 PLANNING

Cranbrook Basements26-28 Hammersmith Grove,Hammersmith,London, W7 7BAT +44 (0)208 551 5555F +44 (0)208 551 1580admin@cranbrook.co.ukwww.cranbrook.co.uk

Mr & Mrs Bauer

7 Thurloe Street

05 Sept 14 2152_P04-200

LondonSW7 2SS

SCALE

0 5METRES

W.C En-suite Bedroom

Serv

ice

Voi

d

Play Room

Rear Garden

Lightwell

KitchenKitchenDining

Bedroom Bathroom Bedroom

Front Garden

Master BedroomMaster Bathroom DressingRoom

Dining Room Sitting Room

Pave-ment

Plant RoomServiceVoid

7 Thurloe Street

Proposed Section A-A

600

100

heavy ivycovering - min400mm toentirediameter

retaining wall

20 Thurloe Place

T1

Wine Store

© THIS DRAWING IS THE COPYRIGHT OF CRANBROOK BASEMENTS. It shall not be in any way used or reproducedwithout their prior written consent. All dimensions are to be checked on site or in the workshop prior to commencing anywork. Work only to figured dimensions. Any discrepancies are to be reported to the Architect.

Client :

Project :

Drawing :

Scale :

Date :

Rev :

Dwg No :

No. Date Amendment Initials

Status :

Proposed Section AA

1:100 @ A3 PLANNING

Cranbrook Basements26-28 Hammersmith Grove,Hammersmith,London, W7 7BAT +44 (0)208 551 5555F +44 (0)208 551 1580admin@cranbrook.co.ukwww.cranbrook.co.uk

Mr & Mrs Bauer

7 Thurloe Street

05 Sept 14 2152_P04-201

LondonSW7 2SS

DESIGNERS RISK ASSESSMENT Excavations Care must be taken to prevent sides of excavations from collapsing. Suspended Floors The use of suspended insitu reinforced concrete ground slabs is expensive and impractical due to the extent of formwork required and the thickness of slab required. Precast beam and block floors provide reduced weight and quick installation with holes and cutting for designed services carried out on site at the time of installation. However, during installation, and indeed before the floor is screeded, safety netting or air bags shall be provided to prevent injury due to operatives falling between the joists. In-situ concrete slabs cast onto a profiled steel permanent shuttering provides a suitable alternative to the beam and block and removes the need for the netting or air bags. However, the manufacturer should always be consulted about temporary span propping that may be required prior to the concrete achieving it’s design strength. Masonry Walls A 150mm minimum thickness is required for design load resistance and height to thickness ratios. However the blocks tend to be too heavy to manhandle and so load bearing blockwork walls will be specified as 215mm thick and formed from 100mm thick blocks laid on their side. Steel Beams Where possible, large span beams will be spliced to minimise manhandling. Other ways of minimising the weight of steel sections is to specify two channels bolted back to back in lieu of a single UB or UC section. However, there will be occasions where neither option will be practical and/or possible and the Contractor will be made aware of such situations. Hazards & Risks Which Cannot be Designed Out

Potential Hazards Action Required Risk Assessment Falls from Height Works being carried out -

provide hand rails and access scaffolding to all openings.

Medium

Falling Debris Works carried out above

public access - provide toe boards, netting and protection fans.

High

Materials Storage Existing roofs and floors

are not to be used for storage of materials without reference to the Engineer or for supporting access scaffolding.

High

Potential Hazards Action Required Risk Assessment Lifting of Steelwork Steel sections to be lifted

using mechanical means where unable to be manually lifted.

High

Erection of Steelwork Contractor responsible

for providing method statement for erection procedure, including any temporary bracing.

Medium

Lifting of Timber Timber rafters and joists

to be lifted using mechanical means where unable to be manually lifted.

High

Fixing of Timber Timbers to be fixed in

accordance with good building practice.

Medium

Reinstate Existing Roof Finishes

Method statement to allow for temporary waterproofing if required.

Low

Use of Cutting Equipment – Flame or Disc.

Fire risk - use suitable protective methods – remove inflammable materials.

High

Painting Touch up steelwork with

primer – take precautions against vapour inhalation, eye and skin contact and fire. Wear protective clothing.

Low

Excavation Take precaution against

collapse of excavation and hazards of persons falling in.

High

Precast Concrete units Lift into position using

mechanical assistance. Storage at ground level in a safe manner.

Medium

Insitu Concrete Construction

Take precautions to prevent skin/eye contact. Protect public and site staff from falling objects and spillage. Ensure adequate care when fixing reinforcement.

Medium

Potential Hazards Action Required Risk Assessment Formwork/Falsework Design temporary works

in a manner that makes allowances for all loadings, including accidental loads. Ensure adequate vertical and diagonal bracing. Supports not to be removed until period specified.

Medium

Forming new Openings in Walls

Provide temporary works to support wall and loads above opening. Install new support lintel and reinstate prior to removal of temporary supports.

Medium

SEQUENCE OF OPERATION • The extent of the underpinning work is shown on the MMP Design drawings. • Upon removal of the existing ground floor the external walls shall be fully propped using a

proprietary system design and installed by an appointed specialist.

• The underpinning operations are to be carried out strictly in accordance with the sequence shown on the drawings.

• All concrete to be C35N/mm2 @ 28 days. • Each pin must not exceed 1000mm in length. • A minimum of 24 hours must elapse after completion of dry-packing to one bay and the

excavation of the next. • At least the full width of the existing foundation must be replicated lower down and onto

an acceptable bearing strata. • Excavations are to be kept free of water and the sides of excavations are to be supported

as necessary. • Underpinning in each section should commence as soon as possible after an agreed

formation depth has been achieved. • Building Control will be given 24 hours notice to inspect and approve the required

formation level and suitable bearing strata of the first pin. Any variations in the nature of the sub-strata will be notified immediately.

• The soffit of the exposed foundations is to be cleaned off prior to concreting. • As indicated on the attached drawing the concrete is to be poured to a level approximately

75mm below the existing footings and allowed to cure for a minimum period of 24 hours. The void is then to be filled using a semi-dry cement and sand mix (in a 1:1 proportion) and rammed home to ensure a uniform transfer of load.

• As underpinning work is carried out against already completed bays, the concrete surface

of the adjacent section should be hacked off and keyed to form a good key prior to the new concrete being cast. Starter bars will be drilled and inserted.

• Any supports to the excavations are to be removed progressively as concrete operations

proceed so that no voids exist. • All workmanship and materials must be approved by the BCO.

APPENDIX A

CONSTRUCTION DETAILS

MMP DESIGN

APPENDIX B

DESIGN CALCULATIONS

()

MMPDESIGN Consulting Civil & Structural Engineers

Project 7 THURLOE STREET, SW7

CALCULATION SHEET Title BASEMENT By

SM I Checked

UNIT LOADS in kN/m2

Timber Pitched Roofs

Pitched roof with tiles and battens over felt, unlined but including ceiling below

Pitched roof with tiles and battens over felt, unlined but excluding ceiling below

Pitched roof with tiles and battens over felt, lined and including ceiling below

Pitched roof with tiles and battens over felt, lined but excluding ceiling below

Concrete Flat Roofs

200mm slab with concrete paving, internal finishes and parking for vehicles

200mm slab with !.3m soil and internal finishes

Suspended floors

Timber upper floor including ceiling

Timber ground floor including services and suspended ceiling

200mm Concrete slab with finishes and partition allowance

Allowance for lightweight partitions if position not known

External walls

215 mm solid masonry, plastered one side

330 mm solid masonry, plastered one side

440 mm solid masonry, plastered one side

Timber studwork, tile hung with plasterboard and skim internally

Internal walls

100 mm solid masonry, plastered both sides

I 00 mm timber studwork, lathe and plaster both sides

I 00 mm timber studwork, plasterboard and skim both sides

First Floor, Unit 6

Union Park

Packet Boat Lane

Uxbridge UBS 2GH Tel: 01895 430700 Fax: 01895 430550

Job No. 4208.2

Date

Sheet No.

MAR/14

LD/1 IRev

DEAD IMPOSED

1.35 1.05

!.50

1.20

8.00

29.00

0.50

1.00

8.00

0.00

4.80

7.20

9.50

1.00

2.60

0.60

0.60

0.90

0.65

0.90

0.65

2.50

1.50

!.50

1.50

2.50

1.00

0.00

0.00

0.00

0.00

0.00

0.00

0.00

First Floor, Unit 6

MMPDESIGN Union Park

Consulting Civil & Structural Engineers Packet Boat Lane

Uxbridge UBS 2GH

Tel: 01895 430700 Fax: 01895 430550

Project 7 THURLOE STREET, SW7

Job No. 4208.2

CALCULATION SHEET Title

BASEMENT Date

MAR/14 By

SM !Checked Sheet No. LD/2 I Rev

FOUNDATION LINE LOADS OF BASEMENT WALLS

I WALL !Quantity I Unit load I Line Load I Total

I I Dead I Imposed I Dead I Imposed I Load

BASEMENT LEVEL WALLS B1 & B2

Upper Ground floor 2.00 1.00 1.50 2.00 3.00 5.00

Lower Ground floor 2.00 8.00 2.50 16.00 5.00 21.00

LG- UGwall 2.60 4.80 0.00 12.48 0.00 12.48

Foundation- LG wall 3.80 8.40 0.00 31.92 0.00 31.92

0 I TOTALS (kN/m) 62.40 8.00 1o.4o 1

SUB-BASEMENT LEVEL WALLS S1, S2 & S4

LG level roof 2.60 29.00 !.50 75.40 3.90 79.30

Basement Level 1 floor 2.60 8.00 2.50 20.80 6.50 27.30

Basement Level 2 floor 2.60 8.00 2.50 20.80 6.50 27.30

Foundation- LG roof wall 10.50 8.40 0.00 88.20 0.00 88.20

I TOTALS (kN/m) 205.20 16.90 222.10 1

SUB-BASEMENT LEVEL WALL S3

Flat roof 1.00 1.00 0.75 1.00 0.75 1.75

Upper Ground floor 1.00 1.00 1.50 1.00 1.50 2.50

Lower Ground floor 1.00 8.00 1.50 8.00 !.50 9.50

LG - first wall 3.80 4.80 0.00 18.24 0.00 18.24

LG level roof 2.00 29.00 1.50 58.00 3.00 61.00

Basement Level 1 floor 2.00 8.00 2.50 16.00 5.00 21.00

Basement Level 2 floor 2.00 8.00 2.50 16.00 5.00 21.00

0 Foundation - LG roof wall 10.50 8.40 0.00 88.20 0.00 88.20

!TOTALS (kN/m) 206.44 16.75 223.19 1

()

()

First Floor, Unit 6

MMPDESIGN Union Park

Consulting Civil & Structural Engineers Packet Boat Lane

Uxbridge UBS 2GH

Tel: 01895 430700 Fax: 01895 430550

Project 7 THURLOE STREET, SW7 Job No. - ----------- --------------------------- --- --

CALCULATION SHEET Title BASEMENT Date

By SM Checked Sheet No.

MOMENT DUE TO RETAINED SOIL AND WATER- BASEMENT LEVEL 1

Sandy Gravel density= 19kN/m3 and angle of internal friction= 35 o

HenceKa=

Retained depth (Hr) =

Depth of water (Hw) =

Surcharge (W) =

0.271 m

3.40· m

3.40, m

30.00 kN/m2

and Dd = dry density

Now calculate the maximum pressures from the retained material:

At u/s base ----

Pressure due to dry soil, PI = 0.00 kN/m2

Pressure due to dry soil surcharge, P2 = 0.00 kN/m2

Pressure due to submerged soil, P3 = _________ lj_.4_7 kN/m2

Pressure due to water, P4 = 33.35 kN/m2

Pressure due to surcharge, P5 = ______ _8·!~ kN/m2

Hence the forces acting on the wall due to the retained pressures are:

Force due to dry soil, Fl =

Force due to dry soil surcharge, F2 =

Force due to submerged soil, F3 =

Force due to water, F4 =

Force due to surcharge, F5 =

0.00 kN

0.00 kN

14.39 kN

56.70 kN

27.64 kN

Ds = saturated density

Dw = density of water

=KaxDdx(Hr-Hw)

=KaxDd x (Hr- Hw)

=KaxDsxHw

=DwxHw

=KaxW

=PI x (Hr- Hw) x 0.5

=P2xHw

=P3 x Hwx 0.5

= P4 xHwx 0.5

= P5 xHr

and the overturning moments due to the forces acting on the wall are:

OTM due to dry soil, Ml = 0.00 kN.m = Fl x (Hw + (Hr- Hw)/3)

OTM due to dry soil surcharge, M2 = 0.00 kN.m =F2 x Hwx 0.5

OTM due to submerged soil, M3 = 16.31 kN.m =F3 xHw/3

OTM due to water, M4 = 64.26 kN.m =F4 x Hw I 3

OTM due to surcharge, M5 = 46.99 kN.m =F5 x Hrx 0.5

Therefore, total force due to retained soil and water= 98.74 kN

and total overturning moment due to retained soil and water= 127.57 kN.m

4208.2

MAR/14

BS/1

At top of base

0.00

0.00

7.60

29.92

8.13

0.00

0.00

11.58

45.63

24.80

0.00

0.00

11.78

46.39

37.81

82.01 kN

95.98 kN.m

()

()

MMPDESIGN

Consulting Civil & Structural Engineers

First Floor, Unit 6

Union Park

Packet Boat Lane

Uxbridge UBS 2GH

Tel: 01895 430700 Fa:.;:: 01895 430550

Project 7 THURLOE STREET, SW7 Job No.

- ----- -- ----------

CALCULATION SHEET Title BASEMENT Date

By SM Checked Sheet No.

MOMENT DUE TO RETAINED SOIL AND WATER· BASEMENT LEVEL 3

Sandy Gravel density~ 19kN/m3 and angle of internal friction~ 35 o

- -------

Hence Ka= 0.271 m and -------

Retained depth (Hr) ~ 3.70 m ----------

Depth of water (Hw) ~ 3.70 m . - --------

Surcharge (W) ~ 153.50 kN/m2 ----- -

Now calculate the maximum pressures from the retained material:

At n/s base -------

Pressure due to dry soil, Pl ~ 0.00 kN/m2 -· -- ------

Pressure due to dry soil surcharge, P2 ~ 0.00 kN/m2 ----

Pressure due to submerged soil, P3 ~ 9.21 kN/m2 - -----

Pressure due to water, P4 ~ 36.30 kN/m2

Pressure due to surcharge, P5 ~ 41.60 kN/m2 ·-·

Hence the forces acting on the wall due to the retained pressures are:

----

Force due to dry soil, F 1 ~ 0.00 kN

Force due to dry soil surcharge, F2 ~ 0.00 kN

Force due to submerged soil, F3 ~ 17.05 kN

Force due to water, F4 ~ 67.15 kN

Force due to surcharge, F5 ~ 153.91 kN

Dd ~ dry density

Ds ~ saturated density

Ow~ density of water

~Ka xDd x (Hr- Hw)

~Kax Dd x (Hr- Hw)

~KaxDsxHw

~DwxHw

~KaxW

~ P 1 X (Hr- Hw) x 0.5

~P2xHw

~P3 x Hwx 0.5

~ P4 x Hw X 0.5

~P5 xHr

and the overturning moments due to the forces acting on the wall are:

OTM due to dry soil, Ml ~ 0.00 kN.m ~ Fl x (Hw + (Hr · Hw)/3)

OTM due to dry soil surcharge, M2 ~ 0.00 kN.m ~F2 x Hwx 0.5

OTM due to submerged soil, M3 ~ 21.02 kN.m =F3 xHw/3

OTM due to water, M4 ~ 82.82 kN.m ~ F4 x Hw /3

OTM due to surcharge, M5 = 284.73 kN.m ~ F5 x Hrx 0.5

Therefore, total force due to retained soil and water= 238.11 kN

and total overturning moment due to retained soil and water= 388.57 kN.m

4208.2

MAR/14

BS/2 Rev

At top of_ba_se

0.00

0.00

8.34

32.86

41.60

0.00

0.00

13.97

55.05

139.35

0.00

0.00

15.60

61.47

233.41

208.37 kN

310.48 kN.m

0

REACTIONS & MOMENTS FOR A PROPPED CANTILEVER WITH A TRIANGULAR LOAD

ENTER W= L=

71.10 kN (Tota11oad) 3.40 m (Span)

Hence X= 1.52 m (Location of maximum moment from pinned support)

SUPPORT A IS THE FIXED SUPPORT, SUPPORT B IS THE PIN

MA= M Span=

-32.23 kN.m 14.41 kN.m

RA= RB=

56.88 kN 14.22 kN

REACTIONS & MOMENTS FOR A PROPPED CANTILEVER WITH A UDL

ENTER W= L=

27.64 kN (Total1oad) 3.40 m (Span)

Hence X= 1.28 m (Location of maximum moment from pinned support)

SUPPORT A IS THE FIXED SUPPORT, SUPPORT B IS THE PIN

MA= MSpan=

-11.75 kN.m 6.61 kN.m

BASEMENT LEVEL 1

RA= RB=

17.28 kN 10.37 kN

0

n t

f I L t

tJ:l :> [J)

~ ,..,

"' :> 0 tn :z: !' tJ:l [J) ~ w

_,

~ fil [J)

_§ [J)

:§

""" 0 tJ:l :z: !' ..,. N 0 00 iv

0

REACTIONS & MOMENTS FOR A PROPPED CANTILEVER WITH A TRIANGULAR LOAD

ENTER w~

L~

84.20 kN (Total load) 3.70 m (Span)

Hence X~ 1.65 m (Location of maximum moment from pinned support)

SUPPORT A IS THE FIXED SUPPORT, SUPPORT B IS THE PIN

MA~

MSpan~

-41.54 kN.m 18.57 kN.m

RA~

RB~

67.36 kN 16.84 kN

REACTIONS & MOMENTS FOR A PROPPED CANTILEVER WITH A UDL

ENTER W~

L~

153.90 kN (Total load) 3.70 m (Span)

Hence X~ 1.39 m (Location of maximum moment from pinned support)

SUPPORT A IS THE FIXED SUPPORT, SUPPORT B IS THE PIN

MA~

MSpan~

-71.18 kN.m 40.04 kN.m

BASEMENT LEVEL 3

RA~

RB ~ 96.19 kN 57.71 kN

0

II ! t

i I I t

~

~

"" ~ z ? I:Jj !Zl :;;:

__,

~ ~ !Zl

.~ !Zl

:5

0 I:Jj

z ? 13 0 00 N

()

()

MMPDESIGN Consulting Civil & Structural Engineers

Project 7 THURLOE STREET, SW7

CALCULATION SHEET Title

BASEMENT By

SM Checked

First Floor, Unit 6

Union Park

Packet Boat Lane

Uxbridge UB8 2GH

Tel: 01895 430700 Fax: 01895 430550

Job No. 4208.2

Date MAR/14

Sheet No. BS/5

Rev

ECCENTRIC BASE DESIGN - BASEMENT LEVEL 1

Enter the following:- Dim. a =

Dimb=

Dim cl =

Dimc2=

Dimc3 =

Dimd=

Dime=

OTM=

Load 1 =

Load 2 =

Take moments about the toe

Retaining wall, stem weight =

Retaining wall, base weight =

Lever arm stem =

Lever arm base =

Lever arm vertical load =

Restoring moment =

AppliedOTM=

Total veiiicalload =

Net total moment =

Distance to load centroid =

Hence, eccentricity =

W/A=

M/Z=

Hence, ma.x. pressure=

and min. pressure =

FoS v ove1iurning =

0.150

0.350

0.150

1.200

1.800

0.350

0.000

44.05

70.40

44.40

Case 1

0.00

5.46

0.325

0.325

0.325

24.65

0.00

75.86

24.65

Case 1

0.325

0.000

116.71

0.00

116.71

116.71

N/A

m

m

m

m

m

m

m

kN.m

Note

Case 1 = maximum load from above, no OTM

Case 2 = Case 1 with OTM added

Case 3 = self weight of wall above with OTM

kN/m - maximum vertical load

kN/m - self weight of wall

Case2 Case3

0.00 0.00

14.28 19.32

1.375 1.975

0.850 1.150

1.375 1.975

108.94 109.91

-44.05 -44.05

84.68 63.72

64.89 65.86 a b c

Case2 Case3

0.766 1.034 m

0.084 0.116 m

49.81 27.70 kN/m2

14.72 8.42 kN/m2

64.53 36.12 l<N/m2

35.09 19.29 kN/m2

2.5 2.5

()

()

MMPDESIGN Consulting Civil & Structural Engineers

Project 7 THURLOE STREET, SW7

CALCULATION SHEET Title

BASEMENT By

SM Checked

First Floor, Unit 6

Union Park

Packet Boat Lane

Uxbridge UBS 2GH

Tel: 01895 430700 Fax: 01895 430550

Job No. 4208.2

Date MAR/14

Sheet No. BS/6

Rev

ECCENTRIC BASE DESIGN - BASEMENT LEVEL 3

Enter the following:- Dim. a =

Dimb=

Dim cl =

Dimc2=

Dimc3 =

Dimd=

Dime=

OTM=

Load 1 =

Load 2 =

Take moments about the toe

Retaining wall, stem weight =

Retaining wall, base weight =

Lever arm stem =

Lever arm base =

Lever arm vertical load =

Restoring moment =

AppliedOTM=

Total ve1iicalload =

Net total moment =

Distance to load centroid =

Hence, eccentricity =

W/A=

M/Z=

Hence, max. pressure=

and min. pressure =

FoS y overturning=

0.300

0.350

0.300

1.050

1.700

0.350

0.000

112.70

223.00

136.20

Case 1

0.00

7.98

0.475

0.475

0.475

109.72

0.00

230.98

109.72

Case 1

0.475

0.000

243.14

0.00

243.14

243.14

N/A

m

m

m

m

m

m

m

kN.m

Note

Case 1 = maximum load from above, no OTM

Case 2 = Case 1 with OTM added

Case 3 = self weight of wall above with OTM

kN/m - maximum vertical load

kN/m - self weight of wall

Case2 Case3

0.00 0.00

14.28 19.74

1.225 1.875

0.850 1.175

1.225 1.875

285.31 278.57

-112.70 -112.70

237.28 155.94

172.61 165.87 a b c

Case2 Case 3

0.727 1.064 m

0.123 0.111 m

139.58 66.36 kN/m2

60.36 18.86 kN/m2

199.94 85.22 l<N/m2

79.21 47.50 kN/nl

2.5 2.5

0

0

Project: 7 Thurloe Street & Page: RC/1 London SW7 Made by: SM

Client: Cranbrook Basements Date: Mar/14 Title: New Basement MMP DESIGN Ref No: 4208 .2...

Office: 5831

Location: BASEMENT LEVEL 1

Bending in solid slabs (with comp.steel if reqd.), designed per metre

width, with checks on minimum steel and span/effective-depth ratio

d' Calculations are based on formulae ~ .. (o•) .... (•o•) .. •(•o•) .... (o•)• in Clause 3.4.4.4 of BS8110: Part 1 and thus assume the use of a simplified rectangular concrete stress-block, and that the depth to the neutral axis is restricted to d/2.

TT 0 0 0 0 0 0 0 0 0 0 0 0

j_h I

Design to BS8110(1997) with partial safety factor for steel garnrnaS=1.15 Moment before redistribution Mbef=1.4*44.05

=61.67 kNm per metre width Slab containing section being analysed is considered as non-continuous. Characteristic concrete strength fcu=35 N/rnrn2 Characteristic steel strength fy=500 N/rnrn2 Longitudinal reinforcement is high-yield steel. Diameter of tension bars dia=12 rnrn Nominal concrete cover cover=75 rnrn Overall thickness of slab h=350 rnrn Effective depth of section d=269 rnrn Area of tension steel required As=M*10A6/(z*fy/garnrnaS)

=555.04 rnrn2/metre width. Chosen spacing of tension bars pch=150 rnrn

TENSION REINFORCEMENT SUMMARY

Characteristic strength Diameter of bars Spacing of bars Effective depth Area of steel required Area of steel provided Percentage provided Weight of steel provided

500 N/rnrn2 12 rnrn 150 rnrn 269 rnrn 555.04 rnrn2/m 753 rnrn2/m 0.21514 % 5.91 kg/m2

0

0

Project: 7 Thurloe Street 60 Page: London SW7 Made by:

Client: Cranbrook Basements Date: ·Title: New Basement MMP DESIGN Ref No:

Office:

Check on span/effective-depth ratio

Basic ratio for simp.-sup.slab Mod.factor for tension steel Diameter of compression bars Spacing of comp.bars provided Compression steel provided

bs'd=20 (see Table 3.9) modfl=l. 65 diac=l2 mm pchCA=l50 As'pr=l000/pchCA*PI*diacA2/4

=753.98 mm2 perm

RC/2 SM Mar/14 4208.2:.

5831

Percentage of compression steel per'=l00*As'pr/(1000*d)=0.28029% From Equation 9 of BS8110, with percentage of comp.steel=0.28029 %, Mod.factor for compression steel modf2=l+per'/(3+per')=l.0854 Maximum permissible span/effective-depth ratio Effective span of slab True span/effective-depth ratio As this does not exceed

ps'd=bs'd*modfl*modf2=35.82 span=3 .4 m as'd=lOOO*span/d=l2.639

35.82, this is Acceptable. No 81

0

0

Project: 7 Thurloe Street & Page: RC/3 London SW7 Made by: SM

Client: Cranbrook Basements Date: Mar/14 Title: New Basement MMP DESIGN Ref No: 4208.2.

Office: 5831

Location: BASEMENT LEVEL 3

Bending in solid slabs (with comp.steel if reqd.), designed per metre

width, with checks on minimum steel and span/effective-depth ratio

Calculations are based on formulae in Clause 3.4.4.4 of BS8110: Part 1 and thus assume the use of a simplified rectangular concrete stress-block, and that the depth to the neutral axis is restricted to d/2.

f d-' ----(o) (o) (o) (o)

0 0 0 0 0 0 0 0 0 0 0

Design to BS8110(1997) with partial safety factor for steel gammaS=1.15 Moment before redistribution Mbef=1.4*112.7

=157.78 kNm per metre width Slab containing section being analysed is considered as non-continuous. Characteristic concrete strength fcu=35 N/mm2 Characteristic steel strength fy=500 N/mm2 Longitudinal reinforcement is high-yield steel. Diameter of tension bars dia=20 mm Nominal concrete cover cover=75 mm Overall thickness of slab h=350 mm Effective depth of section d=265 mm Area of tension steel required

Chosen spacing of tension bars

As=M*10A6/(z*fy/gammaS) =1484.1 mm2/metre width.

pch=150 mm

TENSION REINFORCEMENT SUMMARY

Characteristic strength Diameter of bars Spacing of bars Effective depth Area of steel required Area of steel provided Percentage provided Weight of steel provided

500 N/mm2 20 mm 150 mm 265 mm 1484.1 mm2/m 2094 mm2/m 0.59829 % 16.44 kg/m2

0

()

Project: 7 Thurloe Street c50 Page: London SW7 Made by:

Client: Cranbrook Basements Date: Title: New Basement MMP DESIGN Ref No:

Office:

Check on span/effective-depth ratio

Basic ratio for simp.-sup.slab Mod.factor for tension steel Diameter of compression bars Spacing of comp.bars provided Compression steel provided

bs'd=20 (see Table 3.9) modf1=1.187 6 diac=20 rnrn pchCA=150 As'pr=1000/pchCA*PI*diacA2/4

=2094.4 rnrn2 perm

RC/4 SM Mar/14 4208. 2..

5831

Percentage of compression steel per'=100*As'pr/(1000*d)=0.79034% From Equation 9 of BS8110, with percentage of comp.steel=0.79034 %, Mod.factor for compression steel modf2=1+per'/(3+per')=1.2085 Maximum permissible span/effective-depth ratio Effective span of slab True span/effective-depth ratio As this does not exceed

ps'd=bs'd*modf1*modf2=28.703 span=3. 7 m as'd=1000*span/d=13.962

28.703, this is Acceptable. No 81

APPENDIX C

SITE INVESTIGATIONS

F a c t u a l R e p o r tC l i e n t : C r a n b r o o k B a s e m e n t s

S i t e : 7 T h u r l o e S t r e e tL o n d o n S W 7

CSI Re f : F A C T / 3 7 8 7

Da t e d : 7 t h J u n e 2 0 1 3

Che lme r S i t e Inv e s t i ga t i onsUnit 15 , East Hanningf ield Industrial Esta te

Old Church Road, East Hanningfield, Essex CM3 8ABT e l e p h o n e : 0 1 2 4 5 4 0 0 9 3 0 F a x : 0 1 2 4 5 4 0 0 9 3 3

Email: info@siteinvestigations.co.uk Website: www.siteinvestigations.co.uk

Location:

Client: Scale: N.T.S. Date:

Job No: 3787 Weather: Drawn by: JP Checked by: MESunny

Cranbrook Basements

7 Thurloe Street, London SW7

7.6.13Sheet: 1 of 1

Chelmer Site InvestigationsUnit 15 East Hanningfield Industrial Estate

Old Church Road, East Hanningfield, Essex CM3 8ABTelephone: 01245 400930 Fax: 01245 400933

Email: info@siteinvestigations.co.uk Website: www.siteinvestigations.co.uk

SI

C

Notes:

Trial PitBoreholeTree/Shrub

Key:

Rain Water/Soil PipeGully Tree Stump Manhole

G M H

On site tree identification for guidance only. Not authenticated.

BH1(SP)

1.2m

2m

8m

FLOWER BED

PAVED AREA

PLANE(Ht.17m)

NO.7(X3) & BASEMENT

1

Root Information

Remarks:

Description of Strata SampleThick-ness Legend

ResultTypeTest Depth

toWater

DepthMtrs

7.6.131 of 1

3787

N.T.S.Cranbrook Basements

7 Thurloe Street, London SW7

Key: T.D.T.D. Too Dense to DriveD Small Disturbed Sample J Jar SampleB Bulk Disturbed Sample V Pilcon Vane (kPa)U Undisturbed Sample (U100) M Mackintosh ProbeW Water Sample N Standard Penetration Test Blow Count

D

D M

D

D

M

M

D

D

M

M

D

D

M

M

M

D

D

M

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

Sunny

Secondman (100mm Ø) C.F.A.

D 0.5

1.5

2.5D

D

3.5D

D 4.5

D 5.5

No roots observed.

Borehole ends at 10.0m

Client:

Site:

Scale:

Job No:

Sheet No:

Borehole No:

Weather:

Boring method:

Date:

DepthMtrs.

G.L.0.1

10.0

10121214

18202222

22242727

29303133

35384042

42444648

485050(60)50(50)

50(50)50(45)50(20)TDTD

50(40)50(20)TDTD

Chelmer Site InvestigationsUnit 15 East Hanningfield Industrial Estate

Old Church Road, East Hanningfield, Essex CM3 8ABTelephone: 01245 400930 Fax: 01245 400933

Email: info@siteinvestigations.co.uk Website: www.siteinvestigations.co.uk

SI

C

1.7

Drawn by: JP Approved by: ME

1.2

8.8

0.1Astro turf over SAND

MADE GROUND: medium compact, moist,dark brown, very sandy, clayey silt, withgravel and brick fragments.

1.1

Medium dense, moist, orange-brown, silty,very gravelly, fine to coarse SAND. 0.5

Medium dense, moist, orange-brown, silty,gravelly coarse SAND. 7.1

.....becoming medium dense to dense from4.8m.

Medium dense to dense, brown, clayey, silty, gravelly coarse SAND.

1.2

50(40)50(20)TDTD

M

Borehole moist and collapsed to 5.7m on completion.Standpipe installed to 5.7m.

Equipment Used

Chelmer Site Investigations, Unrt 15. East HaM.-.gr101d lnduslnal Estate. Old Church Road.

East HaMingfield. Essex CMJ 8A8

Telephone: 01245 400930 Fax: 01245 400933

Email: lnfo@sitelnvestlgatlons.co.uk Website: www.siteinvestigations.co.uk

REPORT NOTES

'

Hand tools, Mechanical Concrete Breaker and Spade, Hand Augers, 1 00mm/l50mm diameter Mechanical Flight Auger Rig, GE0205 Flight Auger Rig, vVindow Sampling Rig, and Large or Limited Access Shell & Auger Rig upon request and/or access permitting.

On Site Tests

By Pilcon Shear-Vane Tester (Kn/m2) in clay soils, and/or Mackintosh Probe in

granular soils or made ground and/or upon request Continuous Dynamic Probe Testing and Standard Penetration Testing.

Note:

Details reported in trial-pits and boreholes relate to positions investigated only as instructed by the client or engineer on the date shown.

We are therefore unable to accept any responsibility for changes in soil conditions not investigated i.e. variations due to climate, season, vegetation and varying ground water levels.

Full terms and conditions are available upon request.

APPENDIX D

CONSTRUCTION SPECIFICATIONS

SPECIFICATION FOR EARTHWORKS - EXCAVATION AND FILLING MATERIALS Suitable Fill Materials Class I: General Cohesive fill shall include clays with not more than 20% of gravel or any larger sized particles and having a moisture content within -4% to + 2% of the plastic limit unless otherwise stated in Part C. Class II: Well Graded Granular fill which shall include sands and gravel with a uniformity coefficient greater than 10. Class III: Dry Cohesive fills which shall include clays containing more than 20% of gravel or any larger sized particles, and with a moisture content less than 4% below the plastic limit. Class IV: Uniformly Graded fill which shall include sands and gravels with a uniformity coefficient of 10 or less. Classification of Imported Filling Material Imported material for filling shall be classified as follows:- Class A - filling material shall consist of Crushed rock, Hoggin, Well burnt colliery shale and/or Sand and gravel. Class B - filling material shall consist of hardcore. Class C - filling material shall consist of Quarry Stone, Concrete or stone rubble. Class D - filling material shall consist of well graded crushed rock, crushed slag, crushed concrete or well burnt non-plastic shale. Hardcore shall consist of any combination of broken or crushed concrete, clean hard brick, coarse gravel or had stone capable of passing in every direction a ring of diameter not greater than two thirds the thickness of the placed layer subject to a maximum diameter of 150mm. It shall be free from dust, rubbish and any other deleterious matter. WORKMANSHIP All earthworks shall be adequately supported or formed to ensure stability of the sides and to prevent any damage to the surrounding ground or structures. The Contractor shall submit for approval when required method statements for his temporary support arrangements. Surplus excavated materials and excavated material not approved for re-use shall be removed from site to a tip provided by the Contractor unless stated otherwise. Where excavation reveals a combination of suitable and unsuitable materials, the Contractor shall carry out the excavation such that the suitable materials are excavated separately for use in the Works without contamination by the unsuitable materials.

Dealing with Water The Contractor shall not permit water to accumulate in any excavation unless otherwise instructed. Any water whether arising from the excavation or draining into it shall be drained or pumped to an approved location via adequate settlement arrangements or other means to prevent the deposition of solids or other pollution into the receiving watercourse. The Contractor shall take adequate steps to prevent adjacent ground from being adversely affected by loss of fines through natural drainage or any dewatering process and shall submit his proposals for dealing with water. Excavation For excavations in cohesive materials the final 150mm of material above formation level shall only be removed immediately prior to placing the blinding protection concrete when the work can be programmed to be carried out during the same day. Unsuitable hard or soft material encountered at formation levels shall be removed and made good. The Contractor shall make good at his own expense any parts of the formation and sides of excavations made unsuitable by his working methods. The Contractor shall take care when excavating adjacent to existing structures to ensure undermining of existing foundations does not occur. Contractor shall design and install temporary earthwork supports where necessary – the design shall take account of all possible loading conditions. Filling Backfilling shall consist of approved suitable excavated material as specified which shall be deposited in layers not exceeding 250mm loose depth. Due regard shall be paid to the method of backfilling and of compaction to ensure that no damage is done to any structure, including pipes and services. Care shall be taken to ensure that the filling to all trenches and excavations proceeds at the same rate as the timbering or other supports are removed. Filling around structures shall be carried out in such a manner as to avoid uneven loading of the structure and only at such time as any Works have achieved adequate strength to accept the loading. All materials placed as filling or embankments shall be compacted as soon as possible after deposition. The permitted depth of each layer of fill is dependent upon the type of fill to be consolidates and the compaction plant which will be used. The Contractor’s proposals for compaction shall be submitted to the Engineer. The submission shall include full details of the type of plant and method of operation to be used. Regardless of the method of compaction he proposes to use, the Contractor shall compact the filling to the specified density.

Tests shall be carried out in accordance with Clauses in this Specification to measure the actual density achieved. Wherever low test results are obtained the Contractor shall improve the degree of compaction to the specified level and carry out additional tests. Compaction of Hardcore Each layer of hardcore shall be compacted and the degree of compaction obtained on layers not exceeding 300mm thick shall be not less than that which would be obtained by six passes with a vibration-plate compactor with a static pressure under the baseplate of not less than 17 kN/m2. QUALITY CONTROL Sample loads of imported filling material and hardcore shall be supplied for approval. Before using fill materials in permanent earthworks the Contractor shall carry out five compaction tests using BS: 1377, Part 4, Section 3 Clause 3.5 to determine the dry density/moisture content relationship for each classification of fill material he proposed to use and submit the results of these tests to the Employer’s Agent for information. Formation levels shall be within zero and -25mm of the levels shown on the Drawings. Other earthworks levels shall be within zero and -100mm of the levels shown on the Drawings. Settlement and Heave Allowance In the setting out and construction of excavations and filled areas the Contractor shall allow for settlement and heave whether caused by consolidation of fill, settlement of foundations, heave in excavations or change in volume of materials after excavation.

SPECIFICATION FOR UNDERPINNING OF EXISTING FOUNDATIONS GENERAL The Contractor is advised that BS.8004, Code of Practice for Foundations (and amendments), and any requirements or guidance therein are applicable to this Specification. Drawings and Instructions The work shall be carried out in accordance with Engineer's drawings and specifications and to the approval of the District Surveyor or Local Authorities. The contractor shall prepare drawings and calculations showing details of his proposals for temporary works and shall submit these to the Engineer well in advance of work proceeding. These details shall be based on principles of construction shown on Engineer's drawings. Safety of Structure The contractor shall be responsible for the safety of the structure being underpinned during the construction and shall provide all of the shoring, strutting and bracing deemed necessary by him to ensure its safety and stability. Preliminary Information The Contractor shall submit the following information to the Engineer before the work is commenced. a Source of supply of concrete b Source of supply of reinforcement, including test certificates. c Source of supply of cement, including test certificates d Source of supply and other information about aggregates. Responsibilities and Defects The fact that the Contractor has used materials, workmanship, etc. to the satisfaction of the Engineer shall in no way relieve him of his responsibilities in producing work satisfactory in every respect. Any work considered to be unsatisfactory shall be rectified to the satisfaction of the Engineer at the sole cost of the Contractor. Party Wall Awards The Contractor shall obtain confirmation from the Architect that construction of any section of underpinning can commence and that all matters referring to any Party Wall Award have been completed.

MATERIALS General All materials used in normal reinforced and/or unreinforced concrete for the structural underpinning of existing walls and foundations shall comply with the requirements of Clause 2 of the Specification for Concrete and Reinforced Concrete Construction. Concrete The concrete used in underpinning bases shall have the following characteristics: Strength at 28 days; 25N/mm2 Cement; Ordinary Portland or Sulphate Resisting Maximum Coarse Aggregate Size; 20 mm. Cement Content; min. 290 Kg/m3, max. 360 Kg/m3 Maximum free water/cement ratio WORKMANSHIP General All workmanship and construction with normal reinforced and/or unreinforced concrete for the structural underpinning of existing walls and foundations shall comply with the requirements of Clause 3 of the Specification for Concrete and Reinforced Concrete Construction. Underpinning operations shall be executed in sections in strictly predetermined sequence. The order of work shall be as shown on Engineers' drawings and construction of any section shall not be commenced until underpinning of previous section has been completed and pinned. Excavation All excavation shall be carried out in compliance with all relevant and current statutory regulations and following the safety precautions recommended in Section 11 of BS.8004 and Section 1 Clause 4 of BS.6031 Code of Practice for Earthworks. Excavations shall be of depth and width as shown on Engineer's drawings. Sides of excavations shall be vertical, and adequately shored and retained against subsidence or slip of soil. Soil face behind the underpinning and at formation level shall be undisturbed. Where ground conditions prevent this requirement from being met, the face of excavation shall be grouted and the bottom of excavation shall be blinded immediately after the exposure. Grout shall consist of sharp sand and cement mixed to liquid consistency in proportion similar to that of underpinning. Planking Where indicated, permanent precast concrete poling boards shall be used to retain the excavation face. Holes shall be provided for grouting as necessary.

Temporary planking of other excavation faces shall be in accordance with clause 1.03 of this specification. No planking shall be left in place unless it consists of precast concrete, or steel. Strutting Strutting shall be in accordance with clause 1.3 of this specification and shall be so designed as to permit re-strutting of excavation during construction of underpinning if required. All strutting shall be fixed in position using hardwood folding wedges or jacks capable of transferring, to exposed soil faces, support equal to that offered by ground removed by excavations. Existing Foundations The underside of existing foundations shall be levelled and/or shaped as shown in Engineers' drawings. Loose or deteriorated areas of existing foundations shall be removed and thoroughly cleaned. Concrete Construction of Underpinning Construction shall be in lifts determined by position of strutting frames. Excavations shall be re-strutted against new construction prior to removal of next frame above. Construction shall be completed to within 100 mm of the underside of existing foundations and underpinning then completed as described in clause 3.7 below. The pinning of 75 mm gaps shall be with concrete using 10 mm graded aggregate and cement in semi-dry mix. This operation shall commence not earlier than 48 hours after completing main construction described above. The excavation of adjoining sections shall not take place until at least three days after the pinning of the adjoining section. QUALITY CONTROL All tests and checks on site shall be carried out in the presence of or as directed by the Engineer. The Contractor shall be responsible for carrying out all tests required by this specification or called for by the Engineer and shall arrange for copies of test results to be supplied direct to the Engineer immediately they are available. Before concreting starts the Contractor shall submit the name of the Natlas Accredited Independent Testing Authority he proposes to employ. All sampling and testing of aggregates shall be carried out in accordance with BS.812, and/or using other appropriate standard test procedures.

As soon as the sources of supply of aggregates have been provisionally agreed, the Contractor shall instruct the Testing Authority to carry out the following tests: 1. Sieve analyse 2. Test for clay, silt, dust and shell content 3. Test for organic impurities 4. Analyses for salt content 5. Analyses for sulphates 6. Analyses for alkali metals (K2O and Na2O) contents. The results of these tests shall be submitted for approval as soon as they are available. All works classed as defective shall be cut out and removed from the Works and replaced or otherwise dealt with in a manner agreed with the Engineer.

SPECIFICATION FOR CONCRETE AND REINFORCED CONCRETE CONSTRUCTION GENERAL The Contractor is advised that British Standard BS.8110 Structural Use of Concrete (and amendments) is applicable to this Specification. Preliminary Information The Contractor shall submit the following information of his proposals to the Engineer before work is commenced: - a. Source of supply of concrete. b. Source of supply and test certificates for reinforcing steel. c. Types of water-bars and manufacturer. d. Types of joint fillers and sealants and manufacturer e. Position of all construction joints. f. Source of supply of cement, including test certificates. g. Source of supply and other information about aggregates. Where the specification and drawings allow the Contractor a choice of materials to be used in the Works, the materials chosen and their proposed sources of supply shall be to the satisfaction of the Main Contractor and the Engineer. Responsibilities and Defects The fact that the Contractor has used materials, workmanship, etc. to the satisfaction of the Engineer this shall in no way relieve him of his responsibilities in producing work satisfactory in every respect. Any work considered to be unsatisfactory shall be rectified to the satisfaction of the Engineer at the sole cost of the Contractor. The Contractor shall be responsible for all aspects of temporary works necessary for the support of the new and also the adjacent structures and ground profiles for all conditions of temporary loading likely to be encountered, for the duration of the contract. MATERIALS Concrete shall be made with cement, aggregate and water; no other ingredients shall be used without the written agreement of the Engineer. All materials shall conform to the current relevant British Standard and shall be to the satisfaction of the Engineer. The Contractor shall no alter the source of supply of any material from that initially agreed without the written agreement of the Engineer. Concrete grade shall mean for Designed Mixes the characteristic strength, and for Prescribed Mixes, an arbitrary number to denote the mix. All cement shall be delivered to the site in sealed containers or bulk cement lorries. Provision shall be made to protect cement before use and accidental mixing of different types. The Contractor must ensure that the alkali content of the cement supplied is compatible with the proposed aggregates.

Cement used as a constituent material for concrete shall comply with the requirements of British Standards BS.12 Ordinary Portland Cement, BS.4027 Sulphate Resisting Portland Cement and shall be obtained from a single source unless otherwise agreed. Under no circumstances shall high alumina cement be used. Aggregates used in the manufacture of concrete shall comply with the requirements of BS.882 Aggregates from Natural Sources. The Contractor shall obtain an undertaking from the suppliers of both fine and coarse aggregates of the quality and type selected that sufficient supplies are available to complete the contract. In addition to ensuring compliance with the above the Contractor shall ensure that the combination of the proposed fine and coarse aggregates will not be susceptible in concrete to excessive dimensional changes as a result of alkali reactivity. The limiting requirements for the flakiness index, shell content and mechanical properties shall be as defined in Section 4 of BS.882 together with the following exceptions: aggregates used in construction specified as waterproof shall not have a Flakiness Index exceeding 35 percent or a water absorption rate greater than 3.0 per cent by weight". Aggregates shall not contain more than 1.0 percent hollow shells nor shells of unsuitable shape. The Grading, including the contents of clay, silt and fine clay of fine and coarse aggregates shall comply with the requirements of BS.882. The maximum total chloride content of the fine and coarse aggregates shall be as given in Appendix C of BS.882. Water shall be clean and free from harmful matter that would affect the properties of the concrete. If water for the works is not available from a Public Utility Undertaking supply, approval shall be obtained regarding the source of supply and manner of its use. When so directed the Contractor shall arrange for tests of the water to be carried out in accordance with BS.3148. The Contractor shall obtain the written agreement of the Engineer to all materials, which he proposes to use which are not covered by this Specification. Where the use of proprietary material is agreed it shall be used strictly in accordance with the Manufacturer's instruction and specification, which must be forwarded to the Engineer in advance for consideration. Concrete Designed mixes shall be used for each grade of concrete listed in Table l of this Specification and shall be in accordance with BS.5328 except that the Contractor shall obtain approval for any change in sources of materials and any change in cement content over 20kg/m³. The Contractor may use ready mixed concrete, subject to agreement. The concrete shall comply with BS.5328.

Concrete shall be manufactured from a depot included in the Quality Scheme for Ready Mixed Concrete (QSRMC) and evidence of such inclusion will be required on submission of mix details. In particular concrete will comply with the requirements within the scheme for design mixes. All delivery notes shall be retained by the Contractor and made available to the Engineer for inspection throughout the duration of the contract. Concrete shall be delivered and placed within 1 ½ hours of the water being added. If at any time the Engineer is not satisfied that the ready mixed concrete complies with this specification he may alter the frequency of the sampling. All the constituents for each mix shall be added at the manufacturers' depot. No extra water or other material shall be added after the concrete has left the depot, without prior agreement of the Engineer. 50mm blinding concrete of Grade 10 shall be provided under all reinforced concrete work in contact with the ground unless otherwise directed by the Engineer/Main Contractor. The workability of the concrete shall be such that it can be readily compacted around the reinforcement and into the corners and angles of the Formwork. The water content of the mix shall be the lowest possible compatible with the required workability without giving a water/cement ratio greater than that given in Table l. Reinforcement The reinforcement shall be free from paint, loose mill scale, loose rust, dirt, oil and grease, snow or ice or any other substance which can be shown adversely to affect the steel or concrete chemically or reduce the bond. Reinforcement shall be bent cold in accordance with the Engineer's drawings. All steel reinforcement shall be of the diameter, lengths and form shown on the drawings. High Yield reinforcement shall comply with the requirements BS4449 or BS4461. All high yield reinforcement shall be deformed to comply with Type 2 reinforcement as specified in BS.8110. Steel mesh reinforcement shall comply with BS4483. Miscellaneous Materials Waterbars, where the Engineer specifies their use, shall be of PVC and manufactured by an approved supplier. Site welding to Waterbars will only be allowed on butt joints and is to be in accordance with the Manufacturer's written instructions with all other junctions shall be factory made. Waterbars may be internal or external type depending on application and details. Sizes and types are indicated on the Engineer's drawings. Consideration should be given for the use of Hydrophilic Rubber type water bars used in accordance with the manufacturer’s instructions.

Reinforcement Splices Mechanical reinforcement splices, where specified, shall be supplied by an approved manufacturer and used in accordance with his written instructions. The Contractor shall obtain the Engineer's written agreement for the use of splices where these are not shown on the drawings. QUALITY CONTROL The formwork shall be constructed as to support the concrete in its fluid state together with all subsequently imposed construction loads without appreciable movement or deflection. It shall be sufficiently tight to prevent loss of grout from the concrete and be free from undulations and distortions and stiff enough to prevent damage due to vibration. The formwork shall, unless otherwise directed, have a smooth even face and be so supported as to provide a plain surface with clean and true arrises. No metal part of any device for maintaining formwork in the correct location shall remain permanently within the specified concrete cover to the reinforcement. Where concrete is cast against existing structures or walls etc., the Contractor is to ensure that in placing the concrete he does not overload, disturb or damage the adjacent structure or wall, limiting the height of the concrete pour as necessary. The Main Contractor shall execute under his own supervision all cutting and making good of concrete which may be necessary either for the proper execution of the work under his contract or for the convenience of Sub-Contractors. Damaged formwork shall not be re-used if in the opinion of the Main Contractor or Engineer the making good would impair the surface appearance of the concrete. Formwork supports must be propped by an unyielding support to prevent movement during concreting and subsequently during curing. Not less than two weeks before the start of any pour requiring props, the Contractor shall submit drawings indicating the props he proposes to use, linked to a detailed programme of work. The responsibility for the safe removal of falsework so not to distress or distort the structure shall rest with the Contractor. Where construction joints are not shown on the Engineer's drawings the Contractor shall submit proposals to the Engineer before work starts. The Contractor shall obtain agreement for his proposals for forming and preparing construction joints prior to the work commencing on site. Unless otherwise agreed, these are to be rebated in profile and the surface bush hammered and cleaned prior to pouring the adjacent concrete. Alternatively the surface can be wire brushed while the concrete is green. Unless otherwise stated all cutting and bending of reinforcement shall be in accordance with Clause 7.2 of BS.8110. Reinforcement shall not be bent except as shown in the bending schedules without prior agreement, and then only with a machine designed for that purpose.

Reinforcement shall be fixed in accordance with Clause 7.3 of BS.8110 but no reinforcement shall be welded without the Engineers written agreement. The reinforcement shall be fixed in such a manner that the concrete covers noted on the drawings can be achieved in the final structure. Where spacers are required to maintain the concrete cover to the reinforcement these may be of either concrete or plastics unless otherwise specified. Plastic spacers shall be of an agreed design and where soffits are to be exposed plastic spacers shall be used. Where spacers are required to carry heavy loads plastic spacers shall not be used. All reinforcement shall be accurately placed to conform to the detail drawings. Reinforcement shall be anchored securely in place and shall be tied with ample use of annealed 16 S.W.G. iron wires at each intersection. The Contractor shall detail, supply and fix all chairs, U-bars and spacer bars requiring the reinforcement in the correct position and shall submit details and spacing of reinforcement chairs. Adequate precautions shall be taken at all times to ensure that reinforcement in slabs and beams are not displaced after fixing and during concreting. Any reinforcement that is placed within a concrete section for incorporation in subsequent work shall not be bent out to its final position until the concrete has achieved two thirds of its 28 day strength. Before each concrete pour the Contractor shall give the Engineer or his representative 24 hours notice in writing in order that an inspection may be made before the concrete is placed. Concrete shall be placed continuously up to construction joints while it is still sufficiently plastic for adequate compaction. Concrete shall not be moved by use of poker vibrators. The concrete shall be placed in one continuous operation rising uniformly in the formwork at a rate of not less than 2.0m per hour. The concrete shall not be handled in any manner that may cause segregation. The concrete shall not be placed directly against a vertical form face but shall be caused to flow to this surface during the compaction process. On fair-face work care shall be taken to avoid the form face being splashed with mortar during the placing operation. Running of concrete using poker vibrators is not acceptable. Unless otherwise specified all structural concrete shall be compacted by mechanical vibrators of appropriate type carefully worked around the reinforcement, embedded fixtures and into corners of the formwork. Whenever concrete is being vibrated at least one spare vibrator of each type in use shall be available in case of breakdown. Vibration shall be continued until concrete reaches a state of compaction, when air bubbles cease to break the surface and all loose stones are absorbed into the mass and the surface is free from pockets and is moist and glistening. Internal vibrators shall not be permitted to touch the shutters. They shall not be used to push the concrete along the forms and an ample supply of concrete shall always be available in front of the needle. External vibrators shall be securely clamped to the shutter frames or stiffeners (as in columns) or against the shutter face with chain or vice.

Immediately before the concrete is placed the formwork shall be thoroughly cleaned. All rubbish, chippings, shavings, sawdust, nails and tying wire, and any other deleterious material shall be removed from the interior of the formwork. The Contractor shall submit weekly a complete record of the concrete work done, showing the time and date when concrete was placed in each part of the Works. The method and duration of curing shall be such that the concrete sections will remain free of cracks or significant distortion and shall be such that the concrete will have satisfactory durability and strength. The Contractor shall obtain the agreement of the Engineer for his methods of curing the cast concrete. Before any formwork is removed the Contractor shall ensure that the concrete has attained sufficient strength for striking to proceed. The structure shall not be distorted, damaged or overloaded in any way by the removal of the formwork. The responsibility for the safe removal of any part of the formwork or props shall rest with the Contractor. The minimum periods before removing formwork to structural members shall be in accordance with BS.8110 and Table 3 in this specification shall be used in place of the Table in BS8110. The earlier striking of forms (but not props) may be approved if the Contractor can show that this can be done without damage to the concrete. The making and testing of cubes to establish the period before striking shall be at the Contractor's expense. Permission to strike formwork on the basis of the strength of specially cast cubes will be withdrawn if the Engineer is not satisfied that the strength of the cubes is representative of the strength of the concrete. Notwithstanding the above, formwork props shall remain in position for at least 3 days. Where the member concerned may be called upon to take construction loading from higher floors, the member shall be re-propped down to an unyielding support. Before concreting starts the Contractor shall submit for approval the name of the Independent NATLAS Accredited Testing Authority he proposes to employ. All sampling and testing of aggregates shall be carried out in accordance with BS.812, and/or using any other appropriate standard test procedures. The testing of all concrete shall be carried out in accordance with BS.1881 and/or using any other appropriate test procedures. The sampling of works concrete using designed mixes shall be in accordance with BS.5328 and BS. 1881 except that samples shall be taken at the mixer or at the point of casting as directed. The frequency of sampling shall be not less than that specified in Table 7 in BS. 5328 of this Specification. In special circumstances an increased rate of sampling may be directed. At least one sample of each grade shall be taken on each day that concrete of that particular grade is used.

Samples of concrete shall be taken in accordance with the requirements of this specification at the point and time of delivery. The concrete shall be sampled and tested in accordance with Clause 15 of BS.5328 at least once a day for each mix delivered for the first five days on which that mix is delivered and thereafter for each 40 cubic metres of each mix. For each sample, workability tests shall be carried out and at least two sets of two cubes shall be made, one set for test at 7 days and the other for test at 28 days. The results of these tests shall be submitted with copies of typical manufacturer's certificates for each type of cement used. Defective Works Where, in the opinion of the Engineer, any of the finished Works or the materials or workmanship in any part of the Works fails to comply with this Specification, that part of the Works will be classed as defective. All work classed as defective shall be cut out and removed from the Works and replaced or otherwise dealt with in an approved manner. For the repair of concrete damaged by shrinkage a repair by the Colebrand (or similar approved) system may at the discretion of the Engineer be used, the costs of such work to be met by the Contractor.

TABLE 1 - DESIGNED CONCRETE MIXES Grade

Max. Coarse Aggregate size (mm)

Min. Cement Content (kg/m³) * See Note

Max. Cement Content (kg/m³)

Max. Free Water/Cement Ratio

Min. Crushing Strength at 28 days N/mm²

C50 20 400 600** 0.45 50.0

C45 20 350 550** 0.50 45.0

C40 20 325 500** 0.55 40.0

C35 20 300 450 0.60 35.0

C30 20 275 400 0.65 30.0

C20 20 275 320 0.65 20.0

(C20 IS TO BE USED ONLY IN UNREINFORCED CONCRETE FOUNDATIONS)

TABLE 2 - NOMINAL MIXES FOR UNREINFORCED CONCRETE Nominal Mix Minimum works cube

strength, N/mm² Volume of dry aggregate to 50kg cement

Nominal size of coarse aggregate

7 days 28 days Fine Coarse mm.

1:2:4 10 16 0.07 0.14 20

1:8 7 10 0.28 “all in” ballast 20

1:10 7 10 0.30 “all in” ballast 20/40

TABLE 3 - MINIMUM PERIOD BEFORE STRIKING FORMWORK Surface Temperature of Concrete in degrees Centigrade Location Not less than 16°C Not less than 7°C

Beam sides and columns 12 hours 18 hours

Slab soffits (formwork props undisturbed) 4 days 6 days

Formwork props to slabs 10 days 15 days

Beam soffits (formwork props undisturbed) 10 days 15 days

Formwork props to beams 14 days 21 days

N.B. The periods quoted above apply to Concrete made using both OPC and SRC.