L

Slenderness ratio of a stud about the y-y axis, Xy = -ey-

Section modulus of a stud about the y-y axes, Wy =

Wy y

2 Iy

Second moment of area of a stud about the z-z axis, Iz

Radius of gyration of a stud about the z-z axis, iz

Slenderness ratio of a stud about the z—z axis, Xz Xz — —~

2. Timber strength properties

Table 1.3, strength class C18 (BS EN 338:2003(E), Table 1)

Characteristic compression strength parallel to /c 0.k = 18 N/mm2 the grain, /c.o.k

Characteristic bending strength, /m.y k /m.y.k = 18 N/mm2

Characteristic compressive strength /c.90 k = 2.2 N/mm2 perpendicular to the grain, /c 90 k

Fifth-percentile modulus of elasticity parallel to E0.o5 = 6.0 kN/mm2 the grain, E0.05

3. Partial safety factors

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

Permanent actions, yg YG = 1.35

Variable actions, yq Yq = 1.5

Table 2.2 (UKNA to EN 1990:2002(E), TableNA.AI.I) Combination factor for a variable action, fo = 0.7

Combination factor for a wind action, f 0.w f 0.w = 0.5

Material factor for solid timber, kM

4. Actions

Characteristic permanent compressive action, Gk

Characteristic medium-term compressive variable action, Qk

Characteristic variable lateral (wind) action, Wk

Combined load cases to obtain the design condition for the stud design

(i) Vertical loading - associated with critical design load cases

Design axial loading with permanent action only on the wall, N1d

Design axial loading with permanent action; unfavourable medium-term variable and wind (dominant) actions, N2d

(ii) Associated design lateral loading

Design lateral loading W1d = 0 kN/m2 with permanent action only on the wall, W1d

Design lateral loading with permanent action; unfavourable medium-term variable and wind (dominant) actions, W2d

L2 3

Design moment per stud M2y.d = W2d ■ sstud ■ — M2y.d = 1.19 x 103 N m

0 0

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