Influence of Openings on Shear Capacity of Wooden Walls

The new generations of massive cross-laminated wooden structures are recently becoming more popular in the European market. The new trends are bringing also multi-storey structures. Special attention is paid to buildings located in earthquake prone areas of middle and south Europe. Therefore, the appropriate guidelines for designing have to be set for existing and new timber structural systems to assure their seismic resistance. In design of wood structures, the contribution of fenestrated wall segments (wall segments with openings) is usually not taken into account when calculating the wall shear capacity. Some experimental and analytical studies have shown that fenestrated wall segments may contribute to the earthquake resistance of the wood-frame plywood sheathed walls. The load-bearing capacity and stiffness of fenestrated wood walls are influenced mostly by the size and layout of the openings. To evaluate the shear strength and stiffness reduction for different size and placement of openings in the wall, development of a mathematical model verified against experimental tests, is of paramount importance.The main goals of the experimental research and parametric study presented in this paper are to provide information on how to estimate the racking strength and stiffness of cross-laminated solid wood walls with openings, and to recognize how the shape and the area of the openings influence the shear capacity and stiffness of cross-laminated wood walls. Results from the parametric study were summarised in diagrams that could serve as an excellent tool for estimating the influence of fenestration on the stiffness and load-bearing capacity of cross-laminated solid wood walls. The study has concluded that openings with a total area of up to 30 % of the entire wall surface do not significantly influence the load-bearing capacity of the wall. The stiffness in such cases is reduced about 50 %.