3 Vd

Shear strength is satisfactory

8. Bearing strength

The design load case will be due to a combination of self-weight of the beam plus the permanent and variable loading:

Design value for end reaction, Reacd Reacd — Vd


Design bearing stress, ac 90.d

Design bearing strength, /c.90.g.d

Factored design bearing strength, kc.90 /c.90.d

fc.90.g.d — 2.16 N/mm2 kc.90 ■ fc.90.g.d — 2.16 N/mm2

Bearing strength is OK without need to use a higher value for kc 90

b ef

9. Beam deflection

At the serviceability limit states (SLS) the partial safety factor is 1.

As the member is material having the same creep properties, the mean value of stiffness will be used to derive the instantaneous and the creep deflection of the beam. The greatest value of instantaneous deflection at the SLS will be associated with the largest value of bending moment and will be due to the characteristic combination of the self-weight of the beam plus the permanent and variable loading.

Deflection due to bending and shear effects

Instantaneous deflection due to loading on the beam Uinst:

(a) Deflection due to bending under permanent loading uinst,b,di: Factor a hi a = —

Function k2Sb (Table A6.1)

Bending moment at mid-span, Md>SLS Md.SLS =

Deflection, Minstjbjdl (Table A6.1)

(b) Deflection due to shear under the permanent loading Uinst,sjdl:

Function k2Ss (Table A6.1)

Deflection, Uinst,sjdl (Table A6.1)

(c) Deflection due to bending under the variable loading Uinst,b,e:

0 0

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