Predicting the non-linear behaviour of cross laminated timber shearwalls with cut-out openings

The behaviour and failure mode expected in Cross Laminated Timber (CLT) shearwalls when either window or door openings are incorporated into the shearwalls may be considerably different than that of shearwalls without openings. Despite clear theoretical and experimental evidence of the possible occurrence of significant increase in the deformation contribution of the CLT panels and induce high stress concentrations around openings, limited studies have been conducted on the effect of crack propagation in CLT shearwalls with cut openings. The current study presents two modelling techniques to account for the crack propagation around openings, through concentrated plastic hinge (PHM) and continuous post-elastic (CPEM) models. The proposed models are validated using available experimental results obtained from six full-scale shearwalls in the literature while input parameters, such as the mechanical properties of the CLT panels, are obtained, in part, from component-level experimental investigation on CLT beams conducted by the authors as part of the current study. The impact and advantages of accurately predicting the non-linear behaviour of the CLT panels are investigated through a numerical analysis on a case-study representing a multi-storey shearwall with multiple openings. The results showed the inability of elastic models to predict the inelastic behaviour in the CLT shearwall after the crack opening, and this the study recommends the inclusion of stress redistribution near crack openings and subsequent inelastic behaviour in the analysis.