Aa

Elevation of built-up column Fig. E8.8.4.

1. Material and nail properties

Table 1.3, strength class C16 (BS EN 338:2003(E), Table 1)

Characteristic compression strength /c.0.k = 17N/mm2 parallel to the grain, /c 0.k

Mean modulus of elasticity parallel to the grain, £o.mean

Fifth-percentile modulus of elasticity parallel to the grain, E005

Stiffness of each nail fastener at the SLS, Kser

Spacing of each fastener, sp

Eo.mean = 8.0kN/mm2 E0,05 = 5.4kN/mm2 Kser = 928 N/mm sp = 75 mm

2. 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

Combination factor for the quasi-permanent value of a variable action, f2

Table 2.6 (UKNA to EC5, Table NA.3) Material factor for solid timber, yM Material factor for connection,

KM.connection

3. Actions

Characteristic permanent action, Gk

Characteristic variable (imposed) action, Qk

Design compressive action for the permanent action, G d

Design compressive action for the variable (imposed) action, Qd

Design compressive action for the critical load combination, Nd (Table 2.8, equation (c) using the unfavourable condition)

4. Modification factors

Factor for permanent duration loading and service class 2, kmod.med (Table 2.4 (EC5, Table 3.1))

Factor for medium-duration loading and service class 2, kmod.med (Table 2.4 (EC5, Table 3.1))

System strength factor, ksys - not relevant

Deformation factor for timber and service class 2, kdef

5. Column geometric properties

Column length, L

Effective length about the y-y axis, Le.y Effective length about the z-z axis, Le.z Adopting the symbols used for profile (f) Width of solid section member 1, b1

L — 4.5 m Le.y — 1.0 ■ L Le.z — 1.0 ■ L in Figure 8.2 b1 — 200 mm

Gd — 5.4 x 104N Qd — 1.2 x 105N Nd — 1.74 x 105N

Thickness of solid section member 1, h1 Width of solid section member 2, h2 Combined thickness of members 2, b2 Cross-sectional area of section, Atot

Second moment of area about z-z axes, Iz (Table 8.2)

0 0

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