Deflection of cross-laminated timber shear walls for platform-type construction

Cross-laminated timber (CLT) is becoming popular in the North American construction market as a feasible option for mid- to high-rise timber buildings. CLT shear walls are effective in resisting lateral forces resulting from wind and seismic loads and design standards allow to estimate their capacity. These standards however do no not include provisions to estimate the deflection of CLT shear walls. In this paper, formulas are proposed to estimate the in-plane deflection for single and coupled walls in platform-type buildings under lateral loading based on the assumed kinematic behaviour (rocking or combined rocking and sliding). It is postulated that the perpendicular walls and the floors above the shear walls also influence the in-plane deflection. Therefore, in addition to the CLT panel (bending and shear) and the connection contributions (sliding and rocking), also the contributions of perpendicular walls and floors above are accounted for. A parameter study evaluates the influence of connection, including those to perpendicular wall and walls above on the total deflection of single and coupled CLT shear walls. The proposed equations to estimate the deflection of CLT shear walls under lateral loads are compared against full-scale tests and the good agreement suggest that the formulae can be applied in the design of CLT platform-type buildings.