Arup - Structural Scheme Design Guide 2006

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Structural Scheme Design Guide

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Structural Scheme Design Guide December 2006 Version

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Ove Arup & Partners Ltd 13 Fitzroy Street, London W1T 48Q Tel +44 (0)20 7636 1531 Fax +44 (0)20 775 www.arup.com

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Index (1/2)

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THE ARUP STRUCTURAL SCHEME DESIGN GUIDE CONTENTS VER 3.0 I Aug 1998

1. Building Geometry & Anatomy 1.1 1.2 1.3 1.4 1.5

Typical grid dimensions Typical sections Typical service zone requirements Car parks References

4.5.5 4.5.6 4.5.7 4.5.8

4.6Timber 4.6.1 4.6.2 4.6.3 4.6.4

2. Guide toCosts 2.1

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2.2

3.Loads

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Comparative European costs for material supply Relative costs of steel subgrades

3.1 3.2 3.3 3.4 3.5

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Density of materials Dead loading Typical imposed loading Imposed loads on barriers References

4.1 Properties of Structural Materials 4.2 Reinforced Concrete

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4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 4.2.6 4.2.7 4.2.8 4.2.9

Rules of thumb Load factors Beams Slabs Stiffness Columns Creep and Shrinkage Bar and mesh areas and weights References

4.3 Prestressed Concrete '

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4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 4.3.6 4.3.7 4.3.8

Rules of thumb Common strands Common tendons Equivalent loads Allowable stresses at service loads Ultimate bending strength Shear References

4.4 Steel (Non-Composite)

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4.1.1 4.4.2 4.4.3 4.4.4 4.4.5 4.4.6 4.4.7 4.4.8 4.4.9 4.4.1 0 4.4.11

Rules of thumb Load factors Design strength Beam design Columns (and beam columns) Portal Frame sizing Element stiffness Connections Corrosion protection Section properties References

4.5 Composite Steel and Concrete r . i

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4.5.1 4.5.2 4.5.3 4.5.4

Rules of thumb Load factors Bending resistance Shear connectors

Bending strength (during construction) Stiffness Safe load tables References

4.6.5 4.6.6 4.6.7 4.6.8 4.6.9

Rules of thumb Materials supply Grade stresses Sizing of elements in.domestic construction Outline of design rules for timber members Selected timber modification factors Modification factor combinations Deflection Fasteners

4.7 Masonry 4.7.1 4.7.2 4.7.3 4.7.4 4.7.5 4.7.6 4.7.7 4.7.8 4. 7.9 4. 7.10 4.7.11 4. 7.12

Rules of thumb Load factors Material factors Modular dimensions Typical unit strengths Masonry compressive strength Sizing external wall panels Flexural strength of masonry Internal non-loadbearing masonry walls Freestanding masonry walls Joints Other issues

4.8 Aluminium 4.8.1 4.8.2 4.8.3 4.8.4

Main structural alloys Durability Typical physical properties Design

4.9 Stainless Steel 4.9.1 4.9.2 4.9.3 4.9.4 4.9.6 4.9.7

Material grades Mechanical properties Physical properties Design strength Availability References

5. Foundations 5. 1 5.2 5.3 5.4 5.5

General Principles Appropriate foundation solutions Presumed allowable bearing values under vertical, non-eccentric static loading Shallow foundations Piled foundations

6. Water Resistant Basements 6.1 6.2 6.3 6.4 6.5 6.6 6.7

Rules of thumb Establish client's requirements/expectations Construction options Waterproofing options Critical points Construction joints Movementjoints

' THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.0 I Aug 98

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Index (2/2)

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6.8

References

7. Fire 7.1 7.2 7.3 7.4 7.5

Minimum periods of fire resistance Fire protection to steel elements Fire protection for reinforced concrete Fire protection for masonry Fire requirements for timber

APPENDIX A Mathematical Formulae A.1 A.2 A.3 A.4 A.5 A.6

Trigonometric functions Hyperbolic functions Standard indefinite integrals Standard substitutions for integration Geometrical properties of plane sections Conversion factors

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APPENDIX B Analysis Formulae 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8

Elastic bending formulae Elastic torsion formulae Taut wires, cables or chains Vibration Design formulae for beamscantilever Design formulae for beams -fixed both ends Design formulae for beams- simply supported Design formulae for beams - propped cantilever

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APPENDIX C Useful Design Data C.1 C.2 C.3 C.4 C.5 C.6 C.? C.8 C.9 C.10

C.11 C.12 C.13 C.14 C.15

Road transportation limitations Craneage data - double girder Craneage data - double hoist Standard rail sections Typical bend radii- rolled sections Safe loads for 25 tonne capacity mobile crane Standard durbar plate sections RHS sections - standard lengths CHS Sections - standard lengths Carbon steel plate sections - standard sizes Carbon and carbon manganese wide flats - standard sizes Fasteners - mechanical properties and dimensions of typical bolts Fasteners - clearance for tightening Fasteners - high strength friction grip bolts Staircase dimensions

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APPENDIX D Proprietary Components

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D.1 D.2

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D.3 D.4 D.5

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Macalloy bars Composite decking [Richard Lees Ltd] [Ward Multideck 60] Purlin systems [Metsec] Precast hollow composite concrete floors [Bison] Heavy duty anchors [Hilti-Feb 1994]

THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP.IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

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1. Building Geometry and Anatomy (1/4)

1.

BUILDING GEOMETRY AND ANATOMY

1.1

TYPICAL GRID DIMENSIONS 1

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Preferred dimensions:

Offices & retail Some retail outlets Car parks

6.0, 7.2, 9.0, 10.5, 12, 15m grids 5.5m or 11m grids (to suit shop units) (7.5 or 7.2) x (15- 16m) grids (to span full bay)

Modular sizes for horizontal coordinating dimensions of spaces

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Range of space (mm)

Multiples of size (mm)

A. Zones for columns and load bearing walls

200 to 1800

300 or 100

B. Centres of columns and wall zones

from 1200

300 or 100

C. Spaces between column and wall zones

from 1200

300 or 100

from 600

300 or 100

Dimension/space

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D. Openings in walls (e.g. for windows and doorsteps)

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Note: The first preference for the multiple of size in each case is 300

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TYPICAL SECTIONS 1 Modular sizes for vertical coordinating dimensions of spaces

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Dimension/space A. Floor to ceiling, floor to floor (and roof)

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B. Zones for floors and roofs

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C. Changes of floor and roof levels

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D. Openings in walls (e.g. for windows)

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Range of space (mm)

Multiples of size (mm)

up to 3600

100

from 3600 to 4800

300

above 4800

600

100 to 600

100

above 600

300

300 to 2400

300

above 2400

600

300 to 3000

300 or 100

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1. Building Geometry and Anatomy (2/4)

1.3

TYPICAL SERVICE ZONE REQUIREMENTS

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DEALERS NORM SPACE

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STRUCTURAL ZONE

SERVICES ZONE

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850/1000

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RAISED FLOOR

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...., DUCT LEAVING RISER/CORE CONSIDER UNIVERSAL COLUMNS AS BEAMS

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VAV TERMINAL BOX

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A B C D E F G H

Specified by structural engineer 50mm deflection and tolerance Approx. 500mm HVAC duct or terminal device 50mm support and tolerance 50 - 150mm sprinkler zone 150mm lighting and ceiling zone Specified by Client I Architect Raised floor- data, telecoms., small power. (Specified by M&E : allow for tolerence & precamber)

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...., MAIN DUCT RUN.QUTS BELOW NORMAL MAX BEAM SIZE

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THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY. Ver 3.0 I Aug 98

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1. Building Geometry and Anatomy (3/4)

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CARPARKS Bay sizes (UK) 3

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Car type

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Bay length

Bay width

Turning circle diameter (m)

Long stay

General

Short stay

Between kerbs

Between walls

Standard car

4.75

2.30

2.40

2.50

13.0

14.0

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Large car

5.65

2.60

2.75

2.90

15.0

Disabled persons

4.75

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3.20 min.

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Coaches

12.00

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4.00

-

Approx. 13.5m

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Car geometry - area swept for standard large car3

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Angled parking 3 r ,

Parking angle

Stall width parallel to aisle (m)

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Aisle width (one way)

Bin width

Minimum (m)

Minimum (m)

Preferred (m)

STALL WIDTH PARALLEL TO AISLE

~ Preferred (m)

90

2.40

6.00

6.00

15.50

15.50

80

2.45

5.25

5.25

15.4

15.4

70

2.60

4.50

4.70

15.1

15.3

60

2.80

3.75

4.20

14.4

14.8

50

3.2

3.50

3.80

13.9

14.2

45

3.4

3.50

3.60

13.6

13.7

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Straight ramps: Helical ramps:

rise rise rise rise

1.500m > 1.500m 3.000m > 3.000m

1 in 1 in 1 in 1 in

7 10

10 12

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If at the top of a ramp steeper than 1 in 10 the floor or roof is laid to a fall of 1 in 60 or steeper away from the ramp, a transition length should be provided. The transition length length should be at least 3m and its gradient half that of the ramp.

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THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.0 I Aug 98

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1. Building Geometry and Anatomy (4/4) 3

Headroom

Recommended minimum height: 2.050m through the building. If motorcaravans are to be used, allow approx. 2.300m. Check if there are any specific access requirements e.g. emergency vehicles.

1.5

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REFERENCES 1. BS 6750 : 1986 Modular coordination in building 2. OVE ARUP & PARTNERS, Building Services Concept Design Guide 3. INSTITUTION OF STRUCTURAL ENGINEERS & INSTITUTION OF HIGHWAYS AND TRANSPORTATION, Design Recommendations for Multi-Storey and Underground Car Parks (1984)

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THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

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2. Guide to Costs (1/3)

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2.

This section has been intentionally removed from the Structural Scheme Design Guide.

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GUIDE TO COSTS

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ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR Dec 06 Version

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3. Loads (1/4)

3.

LOADS

3.1

DENSITY OF MATERIALS 1·2

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Density

Material

(kN/m

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25.5-27.8

Aluminium

27.2

Marble

Asphalt, paving

22.6

Mastic

Lightweight

12.6

Mortar, cement

18.9-20.4

Standard

21.2

Mud

16.5- 18.8

22.8

Oils

Brickwork Concrete Facing

19.7 14.1

Cement Chalk, in lumps

11.0-12.6

Clay (in lumps)

11.0

11.0

In bulk

8.8

In barrels

5.7

In drums Plaster

7.1 13.3

Plasterboard

18.8- 22.0

Dry

15.7- 18.8

Clay (moist)

20.4-25.1

Moist

18.1 -19.6

Clay (wet)

20.4-25.1

Wet

18.1 -20.4

Concrete

Normal

24.0

Lightweight Crushed brick Crushed stone

18-20

14.1 - 18.8

17.3-20.4

Snow

13.0 27.4

Glass Iron

12.6- 18.8

Shale Slate, Welsh

Foamed blocks Gravel, clean

Sandstones

12.6 -15.7

14.1 - 17.3 Cast

70.7 111.1

Limestone

Floor finish (screed) 75mm Ceiling boards False ceiling Services: nominal HVAC Demountable lightweight partitions Blockwork partitions External walling: curtain walling and glazing cavity walls {lightweight block/brick)

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78.5 C24

-4.2

C30 Water

1 .2 kN/m 2 on 0.4 kN/m 2 on 0.25kN/m2 0.25kN/m 2 0.4kN/m2 1.0 kN/m 2 on 2.5 kN/m2 on

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-4.6 9.8

25.1

In the absence of specific details, use the following:

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(Softwoods)

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General 1·3

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Fresh C18

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Wet compact

Steel

DEAD LOADING

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Timber

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28.2

75.4

Wrought Lead, cast or rolled

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Clay (dry)

Sand

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Density

Material

(kN/m 3 }

Blockwork

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plan plan

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plan plan

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0.5 kN/m 2 on elevation 3.5 kN/m 2 on elevation

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THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION

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ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY. Ver 3.0 I Aug 98

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3. Loads (2/4)

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3.2.2

Specific dead loading

•

Composite construction 4

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Layer

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Screed

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Typical

Typical Dead Load

Thickness (mm)

on plan kNim 2

Normal

50

1.2

Lightweight Slab

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0.9

Normal

130

Lightweight

2.8-3.3. 2.3-2.6 •

The lower value is for a trapezoidal deck (Ribdeck AL), the higher value is for a re-entrant profile (Holorib).

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Cladding Arrangement

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Cladding 1

Load on Elevation (kNim

2

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Cladding sheeting and fixings

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0.5

Steel wall framing only

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0.25-0.4

Framing + brick panels and windows

2.4

Framing + steel sheeting

0.75

Windows, industrial type Patent glazing:

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0.3

double

0.55

Doors- industrial wood

0.4

Lath + plaster+ studding

0.5

Plate glass I 25mm thick

0.65

Lead plywood

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0.25 single

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Walls

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Wall type

Composition

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Concrete walls

225wall

5.4

12mm plaster each face

0.2

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Masonry wall (280 cavity)

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Party wall

Dead load on elevation (kNim

102.5 brick

2.25

100 lightweight block and plaster

1.15

Cavity wall two 102.5 brick leaves plastered

5.0

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Internal wall

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1.4 2.75

102.5mm brick plastered both sides

4.4

225mm thick plastered both sides

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1OOmm lightweight block plastered both sides

Curtain wall

Glazing + spandrel

1.0

Acoustic wall

265 brick and block

2.5

Partition

Demountable Stud with lath & plaster

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1 on plan 0.76

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3. Loads (3/4) Roofs 1·5

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Dead load on plan (kN/m 2 ) (Assuming flat)

Description

Bituman roofing felts (3 layers including chipping)

0.29

Ceiling tray/panels

0.25

Asphalt (19mm, 25mm)

0.41, 0.58

Tiles (clay laid to 100mm gauge)

0.62-0.70

Concrete tiles interlocking

0.48-0.55

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3.3

TYPICAL IMPOSED LOADING2

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Be generous at scheme design stage Allow for change of use and flexibility of building. Make no allowance for imposed load reductions during the scheme design except when assessing the load on foundations. Intensity of distributed

Use of structure

loading (kNim

2

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5.0

3.6

Banking hall

3.0

2.7

Book stores

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Concentrated load

Assembly areas Bedrooms (hotels, hospitals)

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2.0

1.8

2.4 for each metre of

7.0

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storage height (min 6.5) Churches

3.0

2.7

Classrooms

3.0

2.7

Communal kitchens

3.0

4.5

Corridors

4.0

4.5

Domestic, floor

1.5

1.4

Factories (general industrial)

5.0

4.5

File rooms in offices

5.0

4.5

- compactus

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7.5

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Garages (cars and light vans)

2.5

9.0

Grandstands (fixed seats)

5.0

3.6

Gymnasia

5.0

3.6

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Libraries - reading rooms

4.0

4.5

- mobile racking

4.8 for each metre of

7.0

storage height (min 9.6) Plant I motor rooms etc.

7.5

4.5

Museum floors

4.0

4.5

3.5 2.5.

2.7

4.0

3.6

Rooms with mainframe computers Offices, general Shops (not stock rooms)

4.5

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Th1s may increase up to 5.0 kN/m' depending on the clients requirements, add 1.0 kNim' for lightweight demountable partitions.

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Compact filing system (usually over a small proportion of the floor area e.g. adjacent to cores).

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1 ' j THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY. Ver 3.0 I Aug 98

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3. Loads (4/4)

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3.4

IMPOSED LOADS ON BARRIERS

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3.4.1

The horizontal force F (in kN), normal to and uniformly distributed over any length of 1.5m of a

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barrier for a car park, required to withstand the impact of a vehicle is given by: r '

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where

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Is the gross mass of the vehicle (in kg); is the velocity of the vehicle (in m/s) normal to the barrier; is the ceformation of the vehicle (in mm); is the deflection of the barrier (in mm).

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Variables

Mass of vehicles 2500 kg

m

1500

mass of vehicles

v

4.5

4.5

Oc

10

100

r ' Note : where 8o

r: I ~.

3.5

=0 use F =150 N for mass of vehicle =2500 kg.

REFERENCES

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1. SCI, Steelwork Design Guide to BS 5950 (Vol. 4) (1991) 2. OVE ARUP & PARTNERS, Metric Handbook (1970) 3. IStructE & ICE, Manual for the design of reinforced concrete building structures ("Green Book") (1985) 4. RICHARD LEES Ltd, Steel Deck Flooring Systems 5. BS 6399 - Parts 1 & 2

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Ii...,i THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION I I

ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR

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AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY. Ver 3.0 I Aug 98

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4.1 Properties (1 /1)

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PROPERTIES OF STRUCTURAL MATERIALS Modulus of elasticity, E (kN/mm2 or GPa)

Shear modulus (units of E)

Poisson's ratio

Thermal expansion (X 10-6 K- 1)

Density

Concrete, fcu=35

21 to 33 (at 28 days)

0.42 E

0.20

7-12

24

Concrete, f,.=40 (e.g. prestressed)

22 to 34 (at 28 days)

0.42 E

0.20

7-12

24

205

0.38 E

0.30

12

70

0.37 E

0.33

23

Material

Steel Aluminium alloy Stainless steel

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See section 4.9 105

0.42 E

0.30

16-19

65-95

0.4 E

0.25

11 - 13

70.7

Wrought iron

150-220

0.4 E

0.25

11 - 12

75.4

Timber C18 (softwoods) C24 C30

6.0 (min) 7.2 (min) 8.2 (min)

0.06 E 0.06 E 0.06 E

-

-

-

-3.8 -4.2 -4.6

900 X fk (f• in kN/mm 2 or GPa)

-

-

4-8 (clay) 11-15 (CaSi)

-

-

-

60

Aluminium bronze Cast iron

Masonry Water

Note:

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The values given for concrete above are typical and vary with age, shrinkage and creep

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THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.0 I Aug 98

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r-- -=

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r-= (--" c--::

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c--=

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r--- r

4.2 Reinforced Concrete (1/14)

4.2

REINFORCED CONCRETE

4.2.1

RULES OF THUMB Span/depth ratios for slabs

17 '

Slabs requiring support from beams 600

600

550

550

One-way solid

I

Two-way solid

I

500

500

I 1

E45o

-

Live load kN/rrf

5400 .s:::

~ 6::::::: ~

ro

en 25o

......., ~ ~ ~ ~

200

~

8::::: ~

r-.... ::;;;..--~ iG;:: ~ :::::::

.5

~ 300

........

~

..) ~ ~ ~

-~

L5..

g-350

j!.!!....

E45o 110

5400 .s::: g-350

~ 300

v .......

-~

ro

en 25o 1.,:::::::

150

150

ii=='

100

4

---

15.0

"

~

200

~~ ........ k::::: ~ ~ ~~~

17.5

Live load kN/rrf

~

100 5

6

7

8

9

10

11

12

--

5

4

6

7

8

10

9

11

12

Multiple span (m)

Multiple span (m) Slabs requiring support from columns only 600

800

I

Flat slabs

550 700

./

~500

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E .§.450

E6oo .s .s::: g.5oo

.s::: g-400

"'C

"'C

..c

~350

c\5 400

en

250

200

200 4

5

6

7

8

9

10

11

12

Live load kN/rrf

~

17!;

~

-

~

~

4

5

-

.......-::

[..,...---" ~

c:;::. ~ ~ ~

1-- ~ 6

V':: ~

... ~ ::::--:v / v

5.0

300

300

10

~

l..-::::: ~ /

vv v v

~ ~ .......... ~

~

7

8

9

10

11

12

Multiple span (m) Multiple span (m) 2 Design assumptions : 3 spans. Loads: 1.5kN/m has been allowed in addition to self-weight for finishes and services. Exposure: mild exposure conditions and 2 2 one hour fire resistance. Materials in-situ: C35 concrete, main steel, fy = 460N/mm , mild steel links, fy = 250 N/mm THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. fT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.2 I August 00

ARUP

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4.2 Reinforced Concrete (2/14) Span/depth ratios for

•:: ~~~---"_~~~~;~~~-~~] E'

g

11 1

800

c. 600 ())

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,.--

_.',''

..-"' rI ,

,,

""0

E 500 ro ())

!D 400

/

/

5~~~.!!!.

/

..--r--- /

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700

.s::.

200 kN/m

~

__., . ,..,...-

--

--

~----I

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..,......Jr--

..,...-"

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--

..-"

-------

--..----

--

II ---1

£c.

I I

ro

I

----..L.;125 kN/ITJ ____

Q)

E

_____________!---· 4

7

6

5

30

10

9

,,

,..,.,

E' E

800

~ 700

= a.

Cl> "'0

E ro a>

Jll

1400 kN/m

/

/

1"---l',:>('-',..,.

,. ,...........-

___ / /.......

15

14

13

16

I

200 kN/m

,----·

,. ,-"'

.,.../

/

/

_, I

/

I

// ,/

.,.."..._.../

;~

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j

/

./"

/'

~~~

/

i

,....-.

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_.l

~-/ _.../" ...~1 / ,." ,/...-" ......, _..../' II _,.'

/

-- \

___ .,...,. - _...... - r ) Height/15 (unrestrained at top) Thickness> Height/30 (restrained at top)

l

i

2

Minimum size of elements 6 Where different, values for Hong Kong are in brackets. Minimum dimension, mm width Columns fully exposed Cover to fire width Beams cover thickness Slabs with plain soffit cover thickness Slabs with ribbed open width of ribs soffit and no stirrups cover .... Cover to !llill!l reinforcement Member

4h 450 25 (35) 240 (280) 70 (80) 170 45 (55) 150 150 55

: Fire Rating 2h 300 25 (35) 200 50 125 35 115 110 35

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1h 200 20 (25) 200 45 100 35 90 90 35

l

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J

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'

)

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)

l

Nominal cover Conditions of exposure Mild - protected from adverse conditions 25 20 20* 20* 35 30 Moderate -condensation, soil 25 Severe - severe rain, occasional freezing 40 30 Very severe - sea water spray, severe freezing, salts 50t 40t Extreme - abrasive action, acidic water, vehicles 60t Maximum free water/cement ratio 0.65 0.60 0.55 0.50 3 Minimum cement content (kg/m ) 275 300 325 350 Lowest grade of concrete C30 C35 C40 C45 Cover to .!ill. reinforcement *These covers may be reduced to 15mm provided that the nominal maximum size of aggregate does not exceed 15mm. t Where concrete is subject to freezing whilst wet, air-entrainment should be used. NOTE : This table relates to normal-weight aggregate of 20mm nominal size.

-

-

-

20* 20 25 30 50 0.45 400 C50

2

Reinforcement weights

_.....,

These values are approximate and should be used only as a check on the total estimated quantity: Pile caps Rafts Beams Slabs Columns Walls

3

110- 150 kg/m 3 60- 70 kg/m 3 125- 160 kg/m 3 130-220 kg/m 3 220- 300 kg/m 3 40 - 100 kg/m

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Reinforcement availability Standard sizes (mm): 6, 8, 10, 12, 16, 20, 25, 32, 40 Standard lengths:

> 12mm diameter: 12 metres < 12mm diameter: from a coil

THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.2/ August 00

ARUlP

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4.2 Reinforced Concrete (5/14)

4.2.2 LOAD FACTORS 3 [!

1

'

"

Partial safety factors for loads (Values in brackets are for H.K.) Load combination (including earth and water loading where present)

Earth and Wind Wk adverse beneficial adverse beneficial water, En 1. Dead and imposed 1.0 1.6 (1.7) 1.4* 1.4 (1.5) 0 2. Dead and wind 1.4 1.0 1.4* 1.4 3. Dead, wind and imposed 1.2 1.2 1.2 1.2 1.2 1.2 .. * For pressures ansmg from accidental head of water at ground level, a part1al factor of 1.2 may be used. Note : The HK dead & imposed factors can be reduced to 1.4 & 1.6 provided the procedure outlined in- PNAP 18F is followed.

i. ll.....i i

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Load type Imposed,~

Dead,~

( I

Mu

M -0.15fcubd 2 As - 0.95fy{d-d') 1

"

;

\

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L

---+ compression steel required

_

_ Mu +A o A,- 0.95fy0.8d s

~_. t:>\L_i

where b equals:

I'

0.4 fcubrht(d-0.5hr) for flanged beams, then the neutral axis is in the web and the above formulae are not correct.

J \

THIS DOCUMENT IS COPYRIGKT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.2 I August 00

ARUIP

4.2 Reinforced Concrete (6/14) 2

Maximum and minimum areas of longitudinal reinforcement for beams Minimum tension reinforcement (fy = 460 N/mm2 )

Flanged beams (web in tension):

)

\

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0.0018 bwh 0.0013 bwh

bw/b < 0.4 bw/b ~ 0.4 T- beam L- beam

Flanged beams (flange in tension over a continuous support): Transverse reinforcement in flanges of flanged beams (may be slab reinforcement)

-

0.0026 bwh 0.0020 bwh 0.0015 ht per metre width

Rectangular beam Flanged beam web in compression:

Minimum compression reinforcement:

i

0.002 bh

Rectangular beams with overall dimensions b and h

' J

0.002 bh 0.002 bwh

I i '

Maximum reinforcement (tension and compression): Normally main bars in beams should be not less than 16mm diameter.

j

0.04 bwh

Shea,-3 Minimum provision of links in beams Value of v (N/mmL) Area of shear reinforcement Grade 250 (mild steel) links equal to 0.18% of the Less than 0.5vc horizontal section throughout the beam, except in members of minor structural importance such as lintels 0.5Vc\ \ \ '\ \ ' '\ \ 1\ ~ 10\ '\ '\ 1'\ '\ '\. "\.. \ :\ '\ [\. \ \ '\. '\. 1\. :--.,. "\ ........

6 5 4

3

~~

2

h (mm)

1

= 20~

0 20

30

40

50

)

'

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\

J

'\ '\_ ~ ~ ~ ~'\ ~ ~ ~ I~ ~ ~" ~~ ~ ~ """' ~ [',."1'..'~""-""' ."""-. ~ l'--" ~

"

60

70

80

90

"""

100 110 120 130 140 150 160

Area (m") Notes: 1. feu = 35 N/mm2 , 2. Dead load factor= 1.4, 3. Live load factor = 1.6, 4. The value of d/h is assumed to be 0.85, 5. The ratio ofVettN is assumed to be 1.15, THIS DOCUMENT IS COPYRIGHT AND IS PUBLISHED FOR DISTRIBUTION ONLY WITHIN THE OVE ARUP PARTNERSHIP. IT IS NOT INTENDED FOR AND SHOULD NOT BE RELIED UPON BY ANY THIRD PARTY.

Ver 3.2 I August 00

'

ARUP

-. i )

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!

4.2 Reinforced Concrete (9/14)

4.2.5 STIFFNESS 3

1

i

Typically require :

y

'

(

v

< span/250 < span/350