3. Partial safety factors

Table 2.8 (UKNA to BS EN 1990:2002, Table NA.A1.2(B))) for the ULS

Permanent actions, yG yG = 1.35

Variable actions, yq yq = 1.5

Table 2.2 (UKNA to BS EN 1990:2002, Table NA.A1.1)

Factor for quasi-permanent value f2 = 0.0 of variable action, f2

Material factor for glulam at ULS, ym = 1-25

4. Actions

Self-weight of the beam, Gk.selfwt - as a safe approximation assume that it is based on its greatest depth and is uniform along the beam length

Design action from the self-weight of the beam, Fueifwt

Characteristic permanent action on the beam, Gk.p

Characteristic variable (imposed) short-term action on the beam, Qk.p

Design action from permanent action, short-term action and self-weight for the critical load case at the ULS, Fd.p (Table 2.8, equation (c) using the unfavourable condition variable action)

5. Modification factors

Factor for short-duration loading and service class 1, kmod.short (Table 2.4 (EC5, Table 3.1))

Adopt size factor based on maximum depth = 750 mm, kh (Table 2.11 (EC5, 3.3))

Bearing factor, kc.90 (equation (4.22) (EC5, 6.1.5,(1))

Deformation factor for service class 1, kdef

6. Bending strength

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

Position of the maximum bending stress from the 320 mm deep end under the design loading, x (Table 6.5)

Section modulus about the y-y axis at position x, Wy (Table 6.5)

Design bending stress, am y d (Table 6.5)

Design bending strength, /m,g,d (equation (6.2))

Design compression strength,

The strength reduction factor for a tapered beam with compressive stresses parallel to the tapered edge, km,a

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