## Figure

Procedure for determining punching shear capacity for pad foundations Determine value of factor 3 3 1.0 when applied moment is zero refer to Expressions (6.38) to (6.42) from BS EN 1992-1-1 for other cases) Determine value of vEd,max (design shear stress at face of column) from VEd,max (VEd - PVM) (from Exp. (6.38)) (uod.ft) where u0 is perimeter of column (see Clause 6.4.5 for columns at base edges) deff (dy + dz) 2 where dy and dz are the effective depths in orthogonal directions Determine...

## Acknowledgements

The content of this publication was produced as part of the project 'Eurocode 2 transition from UK to European concrete design standards'. This project was part funded by the DTI under the Partners in Innovation scheme. The lead partner was the British Cement Association. The work was carried out under the guidance of the Concrete Industry Eurocode 2 Group, which consists of representatives from Alan Baxter and Associates Arup British Cement Association British Precast Building Research...

## Analysis

Analysis by computer, includes 15 redistribution at support and < BS EN 1990 A1.2.2 none in the span. & NA, 5.3.1 (6)> MEd (sagging) 20.4 kNm m 18.3 kNm rib VEd 32.5 kN m 29.3 kN rib Note 1 A ribbed slab need not be treated as discrete elements provided rib spacing < 1500 mm, depth of the rib < 4 x its width, the flange is > 0.1 x distance between ribs and transverse ribs are provided at a clear spacing not exceeding 10 x overall depth of the slab. Note 2 As 7.5 m < 85 of 9.0 m,...

## Combinations of actions at ground st floor

A) At ULS, for maximum axial load, Wk is leading variable action. 1.35 (214.6 + 50.1) + 1.5 x 502.9 + 1.5 x 0.7 x 35.7 357.3 + 754.4 + 37.5 1149.2 kN m moment from 1st order analysis 28.4 kNm m l0 400 2325 400 5.8 mm 0 h 30 > 20 mm 20 mm 28.4 + 0.0058 x 1149.2.1 > 0.020 x 1149.2 28.4 + 6.7 > 23.0 35.1 kNm m < 5.2(7), 5.2(9)> < 6.1.4> ** Assuming wind load is lead variable action. b) At ULS, for minimum axial load, Wk is leading variable action. 1.0 x 214.6 - 1.35 x 50.1 - 1.5 x...

## Cover

Cmin maX Cmin.b> Cmin.dur cminb diameter of bar. Assume 32 mm bars and 8 mm links 32 mm to main bars, 32 - 8 24 mm to links cmindur minimum cover due to environmental conditions. Assume XC1. Therefore cnom 25 + 10 35 mm to links Perimeter column (internal environment) Perimeter column (internal environment)

## Deep elements

For deep elements the advice in Eurocode 2 for the side faces of deep beams may be followed. The UK National Annex recommends that 0.2 is provided in each face. The distance between bars should not exceed the lesser of twice the beam depth or 300 mm. For pile caps the side face may be unreinforced if there is no risk of tension developing. Minimum percentage of reinforcement required

## Design fire resistance

Check validity of using Method A and Table 5.2a effective length of column in fire 0.5 x clear height 0.5 x (4500 - 300) 2100 mm < BS EN 1992-1-2 5.3.2, Table 5.2a > c) Check amount of reinforcement < 4 Assuming ufi 0.7 For fire using Method A and Table 5.2a is valid

## Design for beam shear

VEd 394.6 - (0.400 2 + 0 252) x 128.5 336.5 kN < 6.2.1(8)> * 12 no. H20 B (3768 mm2) used to suit final link arrangements. 12 no. H25 used to suit final arrangement of links. By inspection, VRdmax OK and cot 0 2.5 However, for the purpose of illustration check shear capacity, 0.6 1 - fck 250 0.516 35 1.5 23.3 MPa angle of inclination of strut. By inspection, cot-1 0 < < 21.8. But cot 0 restricted to 2.5 and .*. tan 0 0.4. VRd,max 1.0 x 2000 x 090 x 252 x 0.516 x 23.3 (2.5 + 04) 2089.5...

## Design for shear

It is not usual for a slab to contain shear reinforcement, therefore it is only necessary to ensure that the concrete shear stress capacity without shear reinforcement (vRd,c - see Table 7) is more than applied shear stress (vEd VEd ( bd)). Where shear reinforcement is required, e.g. for ribs in a ribbed slab, refer to Chapter 4, originally published as Beams8. vRd,c resistance of members without shear reinforcement, MPa

## Design grid line

D 300 - 30 - 20 - 20 2 240 mm Flexure column strip, sagging MEd 75.5 kNm m By inspection, z 228 mm < Concise EC2 Table 15.5> As MEd fydz 75.5 x 106 (228 x 500 1.15) 761 mm2 m (p 0.32 ) Try H16 250 (804 mm2 m) Deflection column strip By inspection, OK. Flexure middle strip, sagging MEd 37.1 kNm m By inspection, z 228 mm As MEd fydz 37.1 x 106 (228 x 500 1.15) 374 mm2 m By inspection, deflection OK. Try H10 200 B2 (393 mm2 m) Flexure column strip, hogging MEd 113.3 kNm m K MEd bd2fck 113.3 x...

## Design grid line grid similar

300 - 30 - 20 - 20 2 240 mm K MEd bd2fck 95.1 x 106 (1000 x 2402 x 30) 0.055 As MEd fydz 95.1 x 106 (228 x 500 1.15) 959 mm2 m (p 0.40 ) Try H16 200 (1005 mm2 m) Allowable l d N x K x F1 x F2 x F3 where N 26.2 (p 0.40 , fck 30) K 1.2 (flat slab) < Concise EC2 Table 15.10> < Concise EC2 Table 15.11> osn 283 MPa (from Concise EC2 Figure 15.3 and Gk Qk 3.6, 0.3, ys 1.25) S redistribution ratio 1.08 (Js 283 x (959 1005) 1.08 250 F3 310 250 1.24 Allowable l d 26.2 x 1.2 x 1.24 39.0 Actual l...

## Design in each direction using charts

Assuming 8 bar arrangement, centroid of bars in half section 4 > 35 + 8 + 16 + (350 2 - 35 -8 - 16) x 1 4 From Figure 15.5e A6fyk bhfCk 0.45 A. 0.45 x 3502 x 30 500 3308 mm2 4 no. H32 + 4 no. T25 (5180 mm2) OK. In y direction MEd bh2fck _ 128.1 x 106 (3503 x 30) 4 no. H.32. + 4 no. T25 (5180 mm2) OK.

## Design moments M

M moment from 1st order analysis e,NEd effect of imperfections where MEdyy 95.7 + (3570 400) x 8933 x 10-3 > 0.02 x 8933 95.7 + 79.7 > 178.7 175.4 < 178.7 kNm MEd22 18.8 + 79.7 > 178.7 However, imperfections need only be taken in one direction - where they have the most unfavourable effect .'. use MEd22 178.7 with MEdyy 95.7 kNm.

## Design moments MEdz about z axis

Mejz max M02, M0Ed + Mz, M01 + 0.5M2 where eiNEd effect of imperfections where 146.1 + (2965 400) x 1836 > 0.02 x 1836 146.1 + 13.6 > 36.7 equivalent 1st order moment at about 2 axis at about mid height may M0ra (0.6M02 + 0.4M01) > 0.4M02 0.6 x 159.7 + 0.4 x 0 > 0.4 x 159.7 1 r curvature KvK9 fyd (Es x 0.45d) where < 5.8.8.2(3)> < 5.8.8. 3> < Exp. (5.34)> col lcol 3504 12 x 3400 3.68 x 10 M2 nominal 2nd order moment NEde2 (2.08 - 0.83) (2.08 - 0.40) 1.25 1.68 0.74 1 + PPf P...

## Design procedure

A procedure for carrying out the detailed design of flat slabs is shown in Table 1. This assumes that the slab thickness has previously been determined during conceptual design. Concept designs prepared assuming detailed design would be to BS 8110 may be continued through to detailed design using Eurocode 2. More detailed advice on determining design life, loading, material properties, methods of analysis, minimum concrete cover for durability and bond, and control of crack widths can be found...

## Design using charts

MEdyy bh2fck 178.9 x 106 (5003 x 50) 0.03 NEd bhfck 9000 x 103 (5002 x 50) 0.72 < Concise EC2 Figs 15.5a to 15.5e> depth to centroid of reinforcement in half section assuming 12 bar arrangement with H32s 35+8 + (32 2) + (2 6) 500+2 x (35+8+32 2) 3 Figure 5.9 Depth, d2, to centroid of reinforcement in half section Figure 5.9 Depth, d2, to centroid of reinforcement in half section From chart in Concise EC2Figure 15.5d) Asfyk bhfck 0.30 As 0.29 x 500 x 500 x 50 500 7500 mm2

## Designing to Eurocode

This chapter covers the analysis and design of concrete beams to Eurocode 21 which is essentially the same as with BS 81102. However, the layout and content of Eurocode 2 may appear unusual to designers familiar with BS 8110. Eurocode 2 does not contain the derived formulae or specific guidance on determining moments and shear forces. This has arisen because it has been European practice to give principles in the codes and for the detailed application to be presented in other sources such as...

## Draft Version Beams

All advice or information from The Concrete Centre is intended for those who will evaluate the significance and limitations of its contents and take responsibility for its use and application. No liability (including that for negligence) for any loss resulting from such advice or information is accepted by the Concrete Centre or their subcontractors, suppliers or advisors. Readers should note that this is a draft version of a document and will be subject to revision from time to time and should...

## Edge column

The intention of this calculation is to show a typical hand calculation. A 300 mm square column on the edge of a flat slab structure supports an axial load of 1620 kN and first order moments of 38.5 kNm top and -38.5 kNm bottom in one direction only. Using ck 30 MPa and cnom 25 mm. The 250 mm thick flat slabs are at 4000 mm vertical centres. < BS EN 1990 & NA Table NA 2.1> < BS EN 1991 (10 parts) & UK NAs> < BS EN 1990 & NA Tables NA A1.1 & NA A1.2(B)> < BS 8500-1>...

## Eurocode

Eurocode 7 Geotechnical design is in two parts and gives guidance on geotechnical design, ground investigation and testing. It has a broad scope and includes the geotechnical design of spread foundations, piled foundations, retaining walls, deep basements and embankments. Like all the Eurocodes it is based on limit state design principles, which is a significant variation for most geotechnical design. Further guidance related to simple foundations is given in Chapter 6, originally ppublished as...

## Flexural design span AB

300 - 25 - 8 - 20 2 257 assuming 8 mm link at H20 in span 55.5 x 106 (900 x 2572 x 35) 0.027 K' 0.207 or restricting x d to 0.45 K' 0.168 K < K . section under-reinforced and no compression reinforcement required. z (d 2) 1 + (1 - 3.53K)05 < 0.95d (257 2) (1 + 0.951) < 0.95 x 257 251 < 244 z 244 mm But z d - 0.4x x 2.5(d - z) 2.5(257 - 244) 33 mm By inspection, neutral axis is in flange 55.5 x 106 (434.8 x 244) 523 mm2 rib Allowable l d N x K x F1 x F2 x F3 where N Basic l d check...

## Flexural design support A

MEd,min 1148 x 0.25 in hogging and in sagging 287 kNm bf (0.2bi + 0.1 0) < 0.2 l0 < bi where < 9.2.1.2(1), 9.2.1.4(1) & NA> assuming 10 mm link and H32 in support fck 30 MPa 287 x 106 (350 x 6892 x 30) 0.058 Restricting x d to 0.45 K 0.168 K < K' . section under-reinforced and no compression reinforcement required z (d 2) 1 + (1 - 3.53K)05 < 0.95d (689 2) (1 + 0.89) < 0.95 x 689 652 < 654 z 652 mm fyd 500 1.15 434.8 MPa 287 x 106 (434.8 x 652) 1012 mm2 ' The distance l0 is...

## Flexural design support B

MEd 657.4 - 0.2 x 517.9 + 0.202 x 128.5 2 657.4 - 101.0 556.4 kNm d 300 - 25 cover - 12 fabric - 8 link - 16 bar - 25 2 bar 226 mm Figure 4.20 Section at solid rib intersection Figure 4.20 Section at solid rib intersection K 556.4 x 106 (2000 x 2262 x 35) 0.156 By inspection, K < K' K' 0.167 maximum (or for S 0.85, K' 0.168) .'. No compression steel required z (226 2) 1 + (1 - 3.53 K')05 (226 2) 1 + (1 - 3.53 x 0.156)05 (226 2) (1 + 0.67) < 0.95d 189 mm 556.4 x 106 (434.8 x 189) 6770 mm2...

## Flexural design support C

At centreline of support M 516.0 kNm At face of support < 5.3.2.2(3)> MEd S10.O - 0,2 x 402,0 + 0.202 x 1285 2 K 426.0 x 106 (2000 x 2262 x 35) 0.119 By inspection, K < K' z (226 2) 1 + (1 - 3.53 K)05 (226 2) 1 + (1 - 3.53 x 0.119)05 (226 2) (1 + 0.76) < 0.95d 199 mm 426.0 x 106 (434.8 x 199) 4923 mm2

## Flexure

The design procedure for flexural design is given in Figure 2 this includes derived formulae based on the simplified rectangular stress block from Eurocode 2. Table 3 may be used to determine bending moments and shear forces for beams, provided the notes to the table are observed. Bending moment and shear coefficients for beams Bending moment and shear coefficients for beams a 0.55 (G + Q) may be used adjacent to the interior span. 1 Redistribution of support moments by 15 has been included. 2...

## General

The calculations in this section illustrate 5.2 Design of a non-slender column using design charts. 5.3 Design of a perimeter column using iteration of equations to determine reinforcement requirements. 5.4 Design of an internal column with high axial load. 5.5 Design of a slender column requiring a two hour fire resistance. In general axial loads and first order moments are assumed to be available. The designs consider slenderness in order to determine design moments, MEd. The columns are...

## Idealisation load combination and arrangement

By inspection, Exp. (6.10b) is critical. 47.8 x 1.25 + 45.8 x 1.5 128.5 kN m Idealisation This element is treated as a beam on pinned supports. The beam will be provided with links to carry shear and to accommodate the requirements of Cl. 9.2.5 - indirect support of the ribbed slab described in Section 3.3.8. Arrangement Choose to use all-and-alternate-spans-loaded.

## Load arrangements of actions introduction

< BS EN 1990 4.1.2> < BS EN 1990 4.1.2 (3)> The process of designing concrete structures involves identifying relevant design situations and limit states. These include persistent, transient or accidental < BS EN 1990 3-2 > situations. In each design situation the structure should be verified at the In the analysis of the structure at the limit state being considered, the maximum effect of actions should be obtained using a realistic arrangement of loads. Generally variable actions...

## Load set All or alternate spans loaded

The design values should be obtained from the more critical of All spans carrying the design variable and permanent loads (see Figure 3). Alternate spans carrying the design variable and permanent loads with other spans loaded with only the design permanent load (see Figure 1).The value of gG should be the same throughout. Generally, load set 2 will be used for beams and slabs in the UK as it requires three load arrangements to be considered, while load set 1 will often require more than three...

## Load set Alternate or adjacent spans loaded

The design values should be obtained from the more critical of Alternate spans carrying the design variable and permanent loads with other spans loaded with only the design permanent load (see Figure 1).The value of gG should be the same throughout. Any two adjacent spans carrying the design variable and permanent loads with other spans loaded with only the design permanent load (see Figure 2). The value of gG should be the same throughout.

## Load set Simplified arrangements for slabs

The load arrangements can be simplified for slabs where it is only necessary to consider the all spans loaded arrangement (see Figure 3), provided the following conditions are met In a one-way spanning slab the area of each bay exceeds 30 m2 (a bay means a strip across the full width of a structure bounded on the other sides by lines of support). The ratio of the variable actions (Qk) to the permanent actions (Gk) does not exceed 1.25. The magnitude of the variable actions excluding partitions...

## Material properties

In Eurocode 2 the design of reinforced concrete is based on the characteristic cylinder strength rather than cube strength and should be specified according to BS 8500 Concrete - complementary British Standard to BS EN 206-17 (e.g. for class C28 35 concrete the cylinder strength is 28 MPa, whereas the cube strength is 35 MPa). Typical concrete properties are given in Table 4. Concrete up to class C90 105 can be designed using Eurocode 2. For classes above C50 60, however, there are additional...

## Other designdetailing checks

A6,min 0.26 (fctm fyk) M > 0.0013 btd where Asmin 0.26 x 0.30 x 300667 x 1000 x 144 500 b) Secondary (transverse reinforcement) Minimum 20 Aareq 20 Aareq 0.2 x 502 100 mm2 m Assuming partial fixity exists at edges, 25 of As is required < 9.3.1.2(2)> to extend 0.2 x the length of the adjacent span. Asreq 25 x 639 160 mm2 m Use H10 350 (224 mm2 m) U-bars at edges Curtail 0.2 x 5975 1195 mm, say 1200 mm measured from face of support** < 9.3.1.2(2)> c) Maximum spacing of bars, < 3h <...

## Particular requirements for walls

The minimum area of vertical reinforcement in walls is given by A, 0.002Ac Half of this area should be located at each face. The distance between two adjacent vertical bars should not exceed the lesser of either three times the wall thickness or 400 mm. The minimum area of horizontal reinforcement in walls is the greater of either 25 of vertical reinforcement or 0.001 Ac. However, where crack control is important, early age thermal and shrinkage effects should be considered explicitly.

## Raft foundations

The basic design processes for rafts are similar to those for isolated pad foundations or pilecaps. The only difference in approach lies in the selection of an appropriate method for analysing the interaction between the raft and the ground so as to achieve a reasonable representation of their behaviour. For stiffer rafts (i.e. span-to-thickness greater than 10) with a fairly regular layout, simplified approaches such as yield line or the flat slab equivalent frame method may be employed, once...

## References

BS EN 1997 Eurocode 7 Geotechnical design. BSI (2 parts). 2 BRITISH STANDARDS INSTITUTION. BS 5930 Code of practice for site investigation. BSI, 1999. 3 BRITISH STANDARDS INSTITUTION. BS 8002 Code of practice for earth retaining structures. BSI, 1994. 4 BRITISH STANDARDS INSTITUTION. BS 8004 Code of practice for foundations. BSI, 1986. 5 NARAYANAN, R S & BROOKER, O. How to design concrete structures using Eurocode 2 Introduction to Eurocodes. The Concrete...

## Scope

All foundations should be designed so that the soil safely resists the actions applied to the structure. The design of any foundation consists of two components the geotechnical design and the structural design of the foundation itself. However, for some foundations (e.g. flexible rafts) the effect of the interaction between the soil and structure may be critical and must also be considered. Geotechnical design is covered by Eurocode 71, which supersedes several current British Standards...

## Selected symbols

Symbol Definition Value Symbol Definition Value Ac Cross sectional area of concrete Ac Cross sectional area of concrete Width of section, or width of web on flanged beams Effective depth to compression reinforcement Design value of concrete compressive strength Characteristic cylinder strength of concrete Mean value of axial tensile strength 0.30 ck(2 3) for ck < C50 60 (from Table 3.1, Eurocode 2) Factor to take account of the different structural systems eff Effective span of member See...

## Slabs General

The calculations in this section are presented in the following Sections 3.2 A simply supported slab showing what might be deemed typical hand calculations. 3.3 A detailed version of the same simply supported slab but designed, and curtailment lengths determined, strictly in accordance with the provisions of BS EN 1992-1-1. 3.4 A continuous ribbed slab designed, and curtailment lengths determined, strictly in accordance with the provisions of BS EN 1992-1-1. They are intended to be illustrative...

## Small perimeter column subject to two hour fire requirement

This calculation is intended to show a small slender column subject to a requirement for 2 hours fire resistance. The middle column, B, in Figure 4.5, is subject to an axial load of 1722.7 kN and from analysis moments of 114.5 kNm in the plane at the beam and 146.1 kNm perpendicular to the beam (i.e. about the z axis). The column is 350 mm square, 4000 mm long, measured from top of foundation to centre of slab. It is supporting storage loads, in an external environment (but not subject to...

## Structural design check slenderness

L0 0.5l 1 + k1 (0.45 + k,) 05 1 + k2 (0.45 + k2) 05 where k,, k2 relative stiffnesses top and bottom But conservatively, choose to use tabular method*. For critical direction condition 2 at top and condition 3 at bottom (pinned support). l0 0.95 x 3325 3158 mm Slenderness ratio, X X l0 i where i radius of gyration (I A)05 h 1205 X 3158 x 1205 300 36.5 Limiting slenderness ratio, Xlim Xlim 20 ABC n05 where Assuming min. 4 no. H25 (for fire) m 0.56 as before (1 + 2 x 0.56)05 1.46 1.7 - r Assuming...

## Summary of design

Continuous rectangular beam Summary of design Note It is presumed that the detailer would take this design and detail the slab to normal best practice, e.g. to Standard method of detailing structural concrete 21 . This would usually include dimensioning and detailing curtailment, laps, U-bars and also undertaking the other checks detailed in Section 4.2.8.

## Table S

Z dfor singly reinforced rectangular sections Minimum percentage of required reinforcement a Limitingz to 0.95d is not a requirement of Eurocode 2, but is considered to be go< Minimum percentage of required reinforcement reinforcement in tension reinforcement reinforcement in tension reinforcement

## The design process

This chapter is intended to assist the designer determine all the design information required prior to embarking on detailed element design. It covers design life, actions on structures, load arrangements, combinations of actions, method of analysis, material properties, stability and imperfections, minimum concrete cover and maximum crack widths. The process of designing elements will not be revolutionised as a result of using Eurocode 21, although much of the detail may change - as described...

## Perimeter column internal environment

This example is intended to show a hand calculation for a non-slender internal column using iteration (of x) to determine the reinforcement required. This 300 x 300 mm perimeter column supports three suspended floors and the roof of an office block. It is to be designed at ground floor level where the storey height is 3.45 m and the clear height in the N-S direction (z direction) is 3.0 m and 3.325 m in the E-W direction (y direction). One hour fire resistance is required and ck 30 MPa. From...

## Design moments

The design bending moment is illustrated in Figure 4 and defined as MEd Max M02, Moe + M2, Mo, + 0.5 M2 where Mo, Min Mtop , Mbottom + ei NEd M02 Max Mtop , Mbottom + ei Na ei Max o 400, ft 30, 20 (units to be in millimetres). Mtop, Mbottom Moments at the top and bottom of the column M 0e 0.6 M02 + 0.4 M01 > 0.4 M02 M2 NEd e2 where NEd is the design axial load and e2 is deflection due to second order effects M0, and M02 should be positive if they give tension on the same side. A non-slender...

## Overview

This chapter is taken from The Concrete Centre's publication, How to design concrete structures using Eurocode 2 (Ref. CCIP-006) This chapter is taken from The Concrete Centre's publication, How to design concrete structures using Eurocode 2 (Ref. CCIP-006) A greater understanding of structural behaviour and the ability to analyse that behaviour quickly by computer. The requirement to produce economic designs for slabs whose thicknesses are typically determined by the serviceability limit state...

## Permanent actions

The densities and weights of commonly used materials, sheet materials and forms of construction are given in Table 2.5. Table 2.5 Typical permanent actions 24 Table 2.5 a) Bulk densities for soils and materials Table 2.5 a) Bulk densities for soils and materials Limestone (Portland stone - med. weight) Table 2.5 b) Typical area loads for concrete slabs and sheet materials Quarry tiles including mortar bedding Waffle slabc - standard moulds (325 mm) Waffle slabc - standard moulds (425 mm) Waffle...

## Vertical shear

Eurocode 2 introduces the strut inclination method for shear capacity checks. In this method the shear is resisted by concrete struts acting in compression and shear reinforcement acting in tension. The angle of the concrete strut varies, depending on the shear force applied (see Figure 4). The procedure for determining the shear capacity of a section is shown in Figure 5 (which includes UK NA values) and is in terms of shear stress in the vertical plane rather than a vertical force as given in...

## Design life

The design life for a structure is given in Eurocode Basis of structural design 4.The UK National Annex (NA) to Eurocode presents UK values for design life these are given in Table 1 (overleaf). These should be used to determine the durability requirements for the design of reinforced concrete structures. This chapter is taken from The Concrete Centre's publication, How to design concrete structures using Eurocode 2 (Ref. CCIP-006) This chapter is taken from The Concrete Centre's publication,...

## Accuracy

The calculation of deflection in Eurocode 2 using the rigorous method presented here is more advanced than that in BS 8110 It can be used to take account of early-age construction loading by considering reduced early concrete tensile strengths. However, the following influences on deflections cannot be accurately assessed Tensile strength, which determines the cracking moment. Therefore any calculation of deflection is only an estimate, and even the most sophisticated analysis can still result...

## Design for high beam shear support B

As uniformly distributed load predominates consider at d from face of support VEd 1098 - 350 2 0.689 x 1.35 x 46.0 1.5 x 633 1098 - 0.864 x 157.1 962.3 kN By inspection, shear reinforcement required and cot 0 lt 2.5. Check VRd max to determine 9 Check maximum shear resistance As before 6 0.5 sin-1 0.20 fck 1 - fck 250 gt cot-12.5 where 962.3 x 103 350 x 0.9 x 687 4.45 MPa 6 0.5 sin-1 4.45 0.20 x 30 1 - 30 250 gt cot-12.5 0.5 sin-1 0.843 gt cot-12.5 0.5 x 57.5 gt 21.8 28.7 cot 6 1.824 i.e. gt...

## Flexural design span BC and CD similar

Beff, 0.2b 0.1 0 lt 0.2 0 lt b1 where 7500 - 1000 - 550 2 2975 mm 0 0.70 x 2 0.7 x 7500 5250 mm beff1 0.2 x 2975 0.1 x 5250 lt 0.2 x 5250 lt 2975 1120 lt 1050 lt 2975 1050 mm bw 2000 mm bf2 0.2b2 0.1 0 lt 0.2 0 lt b2 where beff2 0.2 x 3725 0.1 x 5250 lt 0.2 x 5250 lt 3725 1270 lt 1050 lt 3725 1270 mm b 1050 2000 1270 4320 mm assuming 10 mm link and H25 in span fck 30 K 393.2 x 106 4320 x 2522 x 35 0.041 By inspection, K lt K' .'. section under-reinforced and no z d 2 1 1 - 3.53K 05 lt 0.95d 252...

## Table

Bending moment coefficients for flat slabs End support slab connection First Interior Interior End End End End support span support span G.GB6FI -G.G4FI G.G7SFI -G.GB6FI G.G63FI 1 Applicable to slabs where the area of each bay exceeds 30 m2, Qk, lt 1.25 Gk and qk lt 5 kN m2 2 F is the total design ultimate load, l is the effective span 3 Minimum span gt 0.85 longest span, minimum 3 spans 4 Based on 20 redistribution at supports and no decrease in span moments Whichever method of analysis is...

## Minimum area of reinforcement

The minimum area of longitudinal reinforcement in the main direction is As,m 0.26 ctm bt d fyk but not less than 0.0013b d see Table 6 . The minimum area of a link leg for vertical punching shear reinforcement is 1.5ASw,min M gt 0.08 which can be rearranged as Asw,min gt Sr.St F where sr the spacing of the links in the radial direction st the spacing of the links in the tangential direction F can be obtained from Table 10

## Design values of actions

The design value of an action Fd that occurs in a load case is partial factor for the action according to the limit state under consideration. Table 2.6 indicates the partial factors to be used in the UK for the combinations of representative actions in building structures. yFk may be considered as the representative action, Frep, appropriate to the y a factor that converts the characteristic value of an action into a representative value. It adjusts the value of the action to account for the...

## Load arrangements according to the UK National Annex

In building structures, any of the following sets of simplified load arrangements may be used at ULS and SLS See Figure 2.7 . lt 5.1.3 amp NA gt a alternate spans carrying yGGk YqQ with other spans loaded with yGGk and b any two adjacent spans carrying ycGk yQQk with other spans loaded with yGGk. a alternate spans carrying yGGk yQQj lt with other spans loaded with yGGk and b all spans carrying yGGk yQQi lt . Or, for slabs only, all spans carrying yGGk yGGk, provided the following conditions are...

## Deflection

Eurocode 2 has two alternative methods of designing for deflection either by limiting span-to-depth ratio or by assessing the theoretical deflection using the Expressions given in the Eurocode. The latter is dealt with in detail in Chapter 8, originally published as Deflection calculations7. The span-to-depth ratios should ensure that deflection is limited to span 250 and this is the procedure presented in Figure 3. The Background paper to the UK National Annex8 notes that the span-to-...

## Grillage analogy

The Eurocode gives further advice on the equivalent frame method in Annex I and designers used to BS 8110 will find this very familiar. Once the bending moments and shear forces have been determined, the following guidance can be used for the design of flat slabs. This chapter is taken from The Concrete Centre's publication, How to design concrete structures using Eurocode 2 Ref. CCIP-006 This chapter is taken from The Concrete Centre's publication, How to design concrete structures using...

## Check stability

Assume base extends 0.3 m beyond either end of wall A, i.e. is 5.0 m long and is 1.2 m wide by 0.9 m deep Overturning moments Mk 0.51 x 17.2 x 14.1 x 14.1 2 1.5 1057.5 Global imperfections see Figure 6.7 Mk 0.51 x 8.5 x 14.7 11.2 x 11.4 8.1 4.8 1.5 0.51 x 125.0 11.2 x 25.8 0.51 x 414.0 211 kNm lt BS EN 1990 Table A1.2 A amp NA gt Mk 1021.0 5.0 x 1.2 x 0.9 x 25 0 x 225.1 x 0.3 2.2 2890 kNm fn Ya1Qk1 YasupGk 1.5 x 1057.5 1.1 x 211.0 1818.4 kNm Restoring moment fn yG.infGk 0.9 x 2890 2601 kNm i.e....

## Worked Examples for Eurocode

All advice or information from The Concrete Centre is intended for those who will evaluate the significance and limitations of its contents and take responsibility for its use and application. No liability including that for negligence for any loss resulting from such advice or information is accepted by the Concrete Centre or their subcontractors, suppliers or advisors. Readers should note that this is a draft version of a document and will be subject to revision from time to time and should...

## Heavily loaded Lbeam

This edge beam supports heavy loads from storage loads. The variable point load is independent of the variable uniformly distributed load. The beam is supported on 350 mm square columns 4000 mm long. ck 30 MPa yk 500 MPa. The underside surface is subject to an external environment and a 2 hour fire resistance requirement. The top surface is internal subject to a 2 hour fire resistance requirement. Assume that any partitions are liable to be damaged by excessive deflections.

## Flexural design span BC

Bef 0.2b1 0.110 lt 0.2 I0 lt b1 where Assuming beams at 7000 mm cc 7000 - 350 2 3325 mm l0 0.85 x l1 0.85 x 8000 6800 mm beff1 0.2 x 3325 0.1 x 6800 lt 0.2 x 6800 lt 3325 1345 lt 1360 lt 3325 1360 mm bw 350 mm befl2 0.2b2 0.110 lt 0.2 I0 lt b2 where assuming 10 mm link and H32 in span fck 30 MPa . . K 684 x 106 1710 x 6892 x 30 0.028 By inspection, K lt K' .'. section under-reinforced and no lt Appendix A1 gt z d 2 1 1 - 3.53K 05 lt 0.95d lt Appendix A1 gt 689 2 1 0.95 lt 0.95 x 689 672 gt 655...

## Assumptions Eurocode

Design and construction will be undertaken by appropriately qualified and experienced personnel. Adequate supervision and quality control will be provided. Materials and products will be used as specified. The structure will be adequately maintained and will be used in accordance with the design brief. The requirements for execution and workmanship given in ENV 13670 are complied with. ENV 13670 20 is currently available but without its National Application Document. For building structures in...

## Fire resistance

Eurocode 2, Part 1-2 Structural fire design5, gives a choice of advanced, simplified or tabular methods for determining the fire resistance. Using tables is the fastest method for determining the minimum dimensions and cover for beams. There are, however, some restrictions and if these apply further guidance on the advanced and simplified methods can be obtained from specialist literature6 Rather than giving a minimum cover, the tabular method is based on nominal axis distance, a see Figure 1 ....

## First order design moments M

Consider grid C to determine Myyin column According to BS EN 1991-1-1 6.3.1.2 11 the imposed load on the roof is category H and therefore does not qualify for reduction factor an. gk 6.0 6.2 2 x 8.5 51.9 kN m qk 6.0 6.2 2 x 8.5 24.4 kN m Assuming remote ends of slabs are pinned, relative stiffness blcdlc3 Llc buAcXc 0.75 b23d233 L23 0.75 b 21 d 21 3 L 21 b breadth d depth L length 2 x 0.54 4.5 0.75 x 6.1 x 0.33 8.6 0.75 x 6.1 x 0.33 9.6 0.0139 0.0278 0.0144 0.0129 0.252 FEM 23 1.35 x 51.9 x...

## Flat Slabs Design And Construction Ec2

This example is for the design of a reinforced concrete flat slab without column heads. The slab is part of a larger floor plate and is taken from Guide to the design and construction of reinforced concrete flat slabs 29 where finite element analysis and design to Eurocode 2 is illustrated. As with the Guide, grid line C will be designed but, for the sake of illustration, coefficients will be used to establish design moments and shears in this critical area of the slab. The slab is for an...

## Check for punching shear column B

As the beam is wide and shallow it should be checked for punching shear. At B, applied shear force, VFd 569.1 517.9 1087.0 kN Check at perimeter of 400 x 400 mm column P factor dealing with eccentricity recommended value 1.15 VFd applied shear force U control perimeter under consideration. For punching shear adjacent to interior columns u0 2 cx cy 1600 mm d mean d 245 226 2 235 mm vFd 1.15 x 1087.0 x 103 1600 x 235 3.32 MPa v 0.6 1 - fck 250 0.516 fcd accAfck Yc 1.0 x 1.0 x 35 1.5 23.3 vRd,max...

## F r

T S EN1990 Tab Is AU, AI-2 amp NA 1 Depending on the magnitude of gk, qk length AB and BC, yGkinf Sk 1.0 gk may be more critical 2 The magnitude of the load combination indicated are those for Exp. 6.10 of BS EN 1990. The worse case of Exp 6.10a and Exp 6.10b may also have been used. 3 Presuming supports A and B were columns then the critical load combination for Column A would be as Figure 2.18. For column B the critical load combination might be either as Figure 2.17 or 2.18._ c...

## Effective length

Figure 5 gives guidance on the effective length of the column. However, for most real structures Figures 5f and 5g only are applicable, and Eurocode 2 provides two expressions to calculate the effective length for these situations. Expression 5.15 is for braced members and Expression 5.16 is for unbraced members. In both expressions, the relative flexibilities at either end, k1 and k2, should be calculated. The expression for k given in the Eurocode involves calculating the rotation of the...

## Concrete design information

Initially the relevant exposure condition s should be identified. In BS 8500 exposure classification is related to the deterioration processes of carbonation, ingress of chlorides, chemical attack from aggressive ground and freeze thaw see Table 1 . ALL of these deterioration processes are sub-divided. The recommendations for XD and XS exposure classes are sufficient for exposure class XC and it is only necessary to check each face of the concrete element for either XC, XD or XS exposure class....

## Design for biaxial bending

Check MEdz MRdz a MEdy MRdy a lt 1.0 For load case 2 where MRdy moment resistance. Using charts From chart 15.5d, for d2 h 0.20 and Aefyk bhfCk 9648 x 500 500 x 500 x 50 0.39 NEd bhfck 9000 x 103 5002 x 50 MRd 0.057 x 5003 x 50 356.3 kNm lt Concise EC2 Fig. 15.5d gt lt 5.8.3 4 gt Using design actions to Exp 6.10 would have resulted in a requirement for 8500 mm2 500 x 500 x 0.85 x 50 1.5 9648 x 500 1.15 7083 3216 10299 kN NEd NRd 9000 10299 0.87. Interpolating between values given for NEd NRd...

## Plain concrete foundations

Strip and pad footings may be constructed from plain concrete provided the following rules are adhered to. In compression, the value of acc, the coefficient taking account of long-term effects applied to design compressive strength see CI. 3.1.6 , should be taken as 0.6 as opposed to 0.85 for reinforced concrete. The minimum foundation depth, hF, see Figure 8 may be calculated from Minimum percentage of reinforcement required CTgd the design value of the ground bearing pressure ctd the design...

## Analysis grid line grid similar

Consider grid line 1 as being 9.6 2 0.4 2 5.0 m wide with continuous spans of 6.0 m. Column strip is 6.0 4 0.4 2 1.7 m wide. Consider perimeter load is carried by column strip only. lt 5.1.1 4 gt Edge panel on grid 1 grid 3 similar Edge panel on grid 1 grid 3 similar Permanent from slab gk 5 x 8.5 kN m2 42.5 kN m Variable from slab q k 5 x 4.0 kN m2 20.0 kN m Permanent perimeter load gk 10.0 kN m As before, choose to use all-spans-loaded case and coefficients Ultimate load, n By inspection,...

## Design grid line C

D 300 - 30 - 20 2 260 mm Flexure column strip and middle strip, sagging K MEd bd2fck 140.5 x 106 1000 x 2602 x 30 0.069 z d 0.94 z 0.94 x 260 244 mm As MEd fydz 140.5 x 106 244 x 500 1.15 1324 mm2 m p 0.51 Try H20 200 B1 1570 mm2 m Deflection column strip and middle strip, Allowable l d N x K x F1 x F2 x F3 where N 20.3 p 0.51 , fck 30 K 1.2 flat slab F2 1.0 no brittle partitions'1 F3 310 7s where Tsn 500 1.15 x 85 0.3 x 40 16.6 254 MPa or 253 MPa From Concise EC2 Figure 15.3 for Gk Qk 2.1, y 2...

## Analysis grid line C

Consider grid line C as a bay 6.0 m wide. This may be conservative for grid line C but is correct for grid line D etc. 9600 - 2 x 400 2 2 x 300 2 9500 mm lt 5.3.2.2 1 gt 8600 - 2 x 400 2 2 x 300 2 8500 mm Check applicability of moment coefficients 8500 9500 0.89 . . as spans differ by less than 15 of lt Concise EC2 Tables 15.2, 15.3 gt larger span, coefficients are applicable. As two span, use table applicable to beams and slabs noting lt Concise EC2 Table 15.3 gt increased coefficients for...

## Effects of global imperfections in plane of wall A

For medium rise shear walls there are a number of methods of design. Cl. 9.6.1 suggests strut-and- tie see Section xx . Another method ref to Concrete Buildings Design manual is to determine elastic tensile and compression stresses from NEJbi - 6MEd bi2 and determine reinforcement requirements based on those maxima. The method used here assumes a couple, consisting of 1.0 m of wall either end of the wall. The reinforcement in tension is assumed to act at the centre of one end and the concrete...

## BS EN Eurocode Actions on structures

Actions are defined in the 10 parts of BS EN 1991 Eurocode 1 Actions on structures'151 BS EN 1991-1-1 2002 Densities, self-weight, imposed loads for buildings BS EN 1991-1-2 2002 Actions on structures exposed to fire BS EN 1991-1-3 2003 Snow loads BS EN 1991-1-4 2005 Wind actions BS EN 1991-1-5 2003 Thermal actions BS EN 1991-1-6 2005 Actions during execution BS EN 1991-1-7 2006 Accidental actions BS EN 1991-2 2003 Actions on structures. Traffic loads on bridges BS EN 1991-3 2006 Cranes and...

## Related Standards

BS 8500 Concrete - Complementary British Standard to BS EN 206-12 replaced BS 5328 in December 2003 and designers should currently be using this to specify concrete. Further guidance can found in Chapter 11, originally published as How to use BS 8500 with BS 81102. BS 4449 Specification for carbon steel bars for the reinforcement of concrete22 has been revised ready for implementation in January 2006. It is a complementary standard to BS EN 10080 Steel for the reinforcement of concrete23 and...

## Continuous ribbed slabs

This 300 mm deep ribbed slab is required for an office to support a variable action of 5 kN m2 It is supported on wide beams that are the same depth as the slab, as shown in Figure 3.9. One hour fire resistance required internal environment. Ribs are 150 mm wide 900 mm cc. Links are required in span to facilitate prefabrication of reinforcement. Assume that partitions are liable to be damaged by excessive deflections. In order to reduce deformations yet maintain a shallow profile use ck 35 MPa...

## BS EN Eurocode Design of concrete structures

Eurocode 2 Design of concrete structures'141 operates within an environment of other European and British standards - see Figure 1.3. It is governed by Eurocode and subject to the actions defined in Eurocodes 1, 7 and 8. It depends on various materials and execution standards and is used as the basis of other standards. Part 2, Bridges, and Part 3, Liquid retaining structures, work by exception to Part 1-1 and 1-2, that is, clauses in Parts 2 and 3 confirm, moderate or replace clauses in Part...

## The Eurocode family

This chapter shows how to use Eurocode 21 with the other Eurocodes. In particular it introduces Eurocode Basis of structural design2 and Eurocode 1 Actions on structures3 and guides the designer through the process of determining the design values for actions on a structure. It also gives a brief overview of the significant differences between the Eurocodes and BS 81104, which will be superseded and includes a glossary of Eurocode terminology. The development of the Eurocodes started in 1975...

## Vertical loads from wind action moments in plane

Figure 6.3 Lateral stability against wind loads N-S Figure 6.3 Lateral stability against wind loads N-S Check relative stiffness of lift shaft and wall A to determine share of load on wall A. Lift shaft ILs 2.44 12 - 2.04 12 - 0.2 x 1.63 12 1.36 m4 Wall A IwaiiA 0.2 x 4.43 12 . Wall A takes 1.41 1.41 1.36 51 of wind load. Check shear centre to resolve the effects of torsion. Determine centre of reaction of lift shaft ' Includes storeys supporting Categories A residential amp domestic , B office...

## Stability and imperfections Crack control

The effects of geometric imperfections should be considered in combination with the effects of wind loads i.e. not as an alternative load combination . For global analysis, the imperfections may be represented by an inclination 0i. a h 2 R , to be taken as not less than 2 3 nor greater than 1.0 a m 0.5 1 1 rn .5 l is the height of the building in metres m is the number of vertical members contributing to the horizontal force in the bracing system. The effect of the inclination may be...

## Variable actions wind loads

The procedure for determining wind load to BS EN 1991-1-4 is presented below. This presentation is a very simple interpretation of the Code intended to provide a basic understanding of the Code with respect to rectangular-plan buildings with flat roofs. In general maximum values are given with more information a lower value might be used. The user should be careful to ensure that any information used is within the scope of the application envisaged. The user is referred to more specialist...

## Cladding tolerances

Manufacturers may say that their glazed systems can only Deflection may affect cladding or glazing in the following ways When a slab deflects, the load on the central fixings will be relieved and shed to outer fixings. accommodate deflection as low as 5 mm. There should be open discussions between the designers for the various elements to determine the most cost-effective way of dealing with the interaction of the structure and cladding. 1 BRITISH STANDARDS INSTITUTION. BS EN 1992-1-1,...

## Design Aid For Eurocode

The aim of this publication is to illustrate through worked examples how Eurocode 2 1-4 may be used in practice to design in-situ building structures. It is intended that these worked examples will explain how calculations to BS EN 1992 1 1 1 may be performed. This will be carried out within the environment of other relevant publications Material and execution standards. Publications by The Concrete Centre and others. There are, therefore, many references to other documents and while it is...

## Ribbed or waffle slabs

Current practices for determining forces in ribbed and waffle slabs may also be used for designs to Eurocode 2.Where a waffle slab is treated as a two-way slab refer to previous section, but note that their torsional stiffness is significantly less than for a two-way slab and the bending moment coefficients may not be appiicabie.Where it is treated as a flat slab reference may be made to Chapter 7, originally published as Flat slabs4 The position of the neutral axis in the rib should be...

## Variable actions snow loads

In persistent or transient situations, snow load on a roof, s, is defined as being lt bs EN 1991-1-3 5.2 3 gt For flat roofs, 0 - a with no higher structures close or abutting , P1 - P2 - 0.8 For shallow monopitch roofs, 0 lt a lt 30 with no higher structures close or abutting , p1 - 0.8, p2 - 0.8 1 a 30 For other forms of roof and local effects refer to BS EN 1991-1-3 Sections 5.3 and 6 thermal coefficient, Ct - 1.0 other than for some glass-covered roofs, or similar characteristic ground snow...

## Qpa

Informative example applicable to the United Kingdom No risk of corrosion or attack XO class For concrete without reinforcement or embedded metal where there is no significant freeze thaw, abrasion or chemical attack. Unreinforced concrete surfaces inside structures. Unreinforced concrete completely buried in soil classed as AC-1 and with hydraulic gradiant not greater than 5. Unreinforced concrete permanently submerged in non-aggressive water. Unreinforced concrete in cyclic wet and dry...

## Structural design check slenderness about z axis

0z 0.5 1 k1 0.45 k 05 1 k2 0.45 k2 05 lt BS EN 1992-1-2 5.3.3 1 , Annex C amp NA gt lt Exp. 5.15 gt lt PD 6687 2.10 gt k1 3.25 2 x 31.8 0.051 gt 0.1 k1 0.1 k2 by inspection pinned end assumed . 0z 05x 3850 x 1 0.1 0.45 0.1 J05 1 0.45 j05 0.5 x 3850 x 1.087 x 1.41 0.77 x 3850 2965 mm Slenderness ratio, 4 lt 5.8.3.2 1 gt i radius of gyration h 3.46 4 3.46 0z h 3.46 x 2965 350 Limiting slenderness ratio, 4m lt 5.8.3.1 1 gt 4mz 20 ABC n05 lt Exp. 5.13N n relative normal force NEd Acfcd 1836 x 103...

## Longitudinal shear

The shear stress in the vertical plane between the flange and web should be assessed according to section 6.2.4 and Figure 6.7 of the Eurocode reproduced here as Figure 13 . The change in force in the flange can be assessed from the moment and lever arm at a particular location. The Eurocode states that the maximum length that can be considered for the change in force is half the distance between the maximum moment and the point where the moment is zero. Clearly, the maximum longitudinal force...

## Anchorage at end support

As simply supported 50 of As should extend into the support. This lt 9.2.1.2 1 amp Note, 9.2.1.4 2 gt 50 of As should be anchored to resist a force of Fe VEd x al z lt Exp. 9.3 gt ' Maximum z 0.947 at mid span and greater towards support. VEd the absolute value of the shear force a d, where the slab is not reinforced for shear z lever arm of internal forces Fe 29.4 x d 0.95 d 30.9 kN m Anchorage length, bd brqd basic anchorage length required lt red design stress in the bar at the ultimate...

## Internal column

The flat slab shown in Example 3.5 reproduced as Figure 5.6 is part of an eight-storey structure above ground with a basement below ground. The problem is to design column C2 between ground floor and 1st floor. The design forces need to be determined. This will include the judgement of whether to use Exp. 6.10 or the worse case of Exp. 6.10a and Exp. 6.10b for the design of this column. The suspended slabs including the ground floor slab are 300 mm thick flat slabs at 4500 mm vertical centres....

## Punching shear edge column with hole

Check columns D1 and D3 for 200 x 200 mm hole adjacent to column. vRdc for various values of d and p is available from Concise EC2 10 Table 15.6. As previously described use 4 H20 U-bars each side of column for transfer moment. Assuming internal support, VEd 516.5 kN Check at perimeter of column P factor dealing with eccentricity recommended value 1.4 VEd applied shear force U control perimeter under consideration. For punching shear adjacent to edge columns u0 c2 3d lt c2 2c1 400 750 lt 3 x...

## Design moments perpendicular to plane of wall

Figure 6.8 Plan of wall A and location of sections A - A and B - B Figure 6.8 Plan of wall A and location of sections A - A and B - B The slab frames into the wall. For the purposes of assessing fixed end moments, the width of slab contributing to the moments in the wall is assumed to be the length of the wall plus distances half way to adjacent supports either end. Therefore, consider the fixed end moment for 1.50 2 4.40 1.30 2 5.8 m width of adjoining slab framing into the 4.4 m long shear...

## Basis of the worked examples in this publication

The design calculations in this publication are in accordance with BS EN 1990, Eurocode Basis of structural design 14 and its UK National Annex 14a . BS EN 1991, Eurocode 1 Actions on structures in 10 parts 15 and their UK National Annexes 15a . BS EN 1992-1-1, Eurocode 2 - Part 1-1 Design of concrete structures - General rules and rules for buildings. 1 and its UK National Annex 1a . BS EN 1992-1-2, Eurocode 2 - Part 1-2 Design of concrete structures - Part 1-2. Structural fire design.i2 and...

## Reinforced concrete pads

Where the pad foundations require reinforcement the following checks should be carried out to ensure Sufficient reinforcement to resist bending moments. The moments and shear forces should be assessed using the STR combination 1.35 Gk 1.5 Qk STR combination 1 Exp. 6.10 However, there may be economies to made from using Expressions 6.10a or 6.10b from the Eurocode. The critical bending moments for design of bottom reinforcement are located at the column faces. Both beam shear and punching shear...

## Consider slenderness of wall at ground floor max

Effective length, l0 0.75 x 3300 - 200 2325 1 3.46 x l0 h 3.46 x 2325 200 40.2 Limiting slenderness, 1lim 20 ABC n05 where lt Concise Table 5.1 gt lt 5.8.3.2 1 gt lt 5.8.3.1 1 , Exp. 5.13N gt NEd 214.6 x 125 312 x 15 x 0.7 5029 x 15 982 x 15 x 0.7 268.3 32.8 754.4 103.1 1158.6 kN Acfd 200 x 1000 x 0.85 x 30 1.5 3400 kN . n 0.34 . 1lim 20 x 0.7 x 1.1 x 1.95 0.3405 51.5 .'. As 1 lt Alim wall is not slender and .'. no secondary moments

## Load combination and arrangement

By inspection, BS EN 1990 Exp. 6.10b governs . . n 1.25 x 30.2 1.5 x 11.5 Arrangement Choose to use all-and-alternate-spans-loaded load cases, i.e. use coefficients. The coefficients used presume 15 redistribution at supports. As the amount of redistribution is less than 20 , there are no restrictions on reinforcement grade. The use of Table 5.6 in BS EN 1992-1-2 is restricted to where redistribution does not exceed 15 . 50.8 kN m lt BS EN 1990 Exp. 6.10b gt lt 5.1.3 1 amp NA option b, Concise...