Simplified Strategies for the Numerical Modelling of CLT Buildings Subjected to Lateral Loads

Nowadays, cross-laminated timber buildings (CLT) are becoming very popular worldwide thanks to the possibility of having ecological and resistant structures. A strong point of CLT buildings is the ability to withstand the seismic actions but, on the other hand, in seismic design, it is not too easy to model a CLT structure due to the strong non-linear response. In common practice, the Force-Based design method is the most common type of analysis used by structural engineers which require a suitable numerical model in order to represent the correct structural behaviour against seismic loads, which for the case of CLT buildings is not a simple task as it may be for other more common structural materials. The present paper proposes a new way to model CLT structures for linear dynamic analysis, comparing the result of lateral load analysis and a modal analysis with the most popular numerical models present in literature. Based on analytical and validated models, two elastic modules are introduced to consider all types of deformation mechanisms based on orthotopic shell elements. It is shown how this model is able to capture the deformability of a CLT multi-storey structure accounting simultaneously for the sliding and the rocking deformations which are often neglected.