Fig. 12.3. Vector sum of all forces on fastener A.

where n is the number of fasteners in the circle and r is the radius of the fastener group, and Fv,d and Fh d are as previously defined.

The force in the maximum loaded fastener per shear plane must now be shown to be no greater than the lateral design strength per shear plane of the fastener, obtained as described in Chapters 10 and 11 for metal dowel type fasteners and connectors, respectively.

12.5.3 Shear strength and force component checks on connections subjected to a moment and lateral forces Shear strength

In the typical connection discussed in 12.5.2 the vertical and horizontal components of the forces in the fasteners will generate shear forces in the connection members and where these act perpendicular to the grain in a member its shear strength must be checked. Where a rectangular rather than a circular grid of fasteners is to be used, because of the forces in the fasteners in the corner zones it is to be noted that there will be a greater risk of timber splitting. For the connection shown in Figure 12.5, there will be force components from the fastener loads perpendicular to the grain in member 1 and in member 2 and strength checks are required for both members.

When considering member 1, under the force configuration shown in Figure 12.5, for most practical joint configurations the maximum shear force perpendicular to the

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