3 Vd

Bending strength is satisfactory

kv • /v.d = 1.05 N/mm2 Shear strength is satisfactory

With reference to Note 1 above, the design bearing force will equal the design shear force in the beam, Vd:

Design bearing stress, ac 90.d (equation (4.22))

Design bearing strength, /c 0.d (equations (4.22), (4.23) (EC5, equation (6.3)))

/c.90.d = 1.54 N/mm2 Bearing strength is marginally too low - need to use a higher value for kc.90

Adopting value for k 1c.90 = 2.46

(The required increase in value of kc.90 to achieve an acceptable bearing stress) 9. Beam deflection

As the bearing stress factor, kc 90, has exceeded unity by a small % the deflection due to bearing effects can be ignored.

The greatest value of design effect at the SLS will be associated with the largest value of bending moment and shear force obtained from the combinations of load cases that can exist, i.e. for this example: (i) load case (1)+(2)+(3); (ii) load case (1)+(2)+(3)+(4) but with the partial factors set equal to 1. The critical combination will be load case (ii), and it is used to determine the deflection. The effect of the notch at the ends of the beam on deflection is negligible and has been ignored in the calculation.

Deflection due to bending and shear effects:

At the SLS the partial safety factor is 1.

As the member is made from one material, the mean value of stiffness will be used to derive the instantaneous and the creep deflection of the beam. Instantaneous deflection under permanent actions, unto (Table 4.7)

0 0

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