Structural Limitations in the Use of Earthquake-Resistant Proprietary Connections in Multi-Storey Clt Buildings: A Multi-Parametric Numerical Study

Cross-Laminated timber (CLT) structures have gained popularity in the last two decades thanks to the evolution of timber and connection technologies that aims to reach ever taller buildings. Nowadays midrise and high-rise CLT construction, thanks their seismic performance, represent a sustainable alternative to buildings realized with traditional building materials (e.g., steel and concrete). Connections have a crucial role in seismic behaviour of CLT buildings by means a right assurance of ductility and dissipative capacity of the entire system which guarantee the application of the capacity design roles in design stage. This paper analyses the structural limitations of earthquake-resistant proprietary connections (e.g. hold-downs, angle brackets) used in multi-story CLT building. A multi-parametric analysis on selected CLT building was performed paying particular attention to the characterisation of the connections used in the numerical modelling. The influence of different parameters, such as: seismic intensity, number of floors and values of the total shear-walls length per floor unit area was assessed by means of a non-linear elastic analysis. Results of numerical simulations carried out on different configurations or archetype were compared in terms of shear forces affecting the CLT shear-walls in the ground floor. Results obtained in this works provide an important insight for both academics and practicing engineers, showing how the structural limitations of the proprietary earthquake-resistant connections systems affected the seismic behaviour of CLT buildings.