Modelling in-plane dynamic response of a fastening system for horizontal concrete facade panels in RC precast buildings

The paper presents experimental and analytical studies of the dynamic in-plane response of typical fastening systems for horizontal cladding panels in RC precast industrial buildings in Central Europe. The system consists of two main parts: a pair of top bolted connections, which provide the horizontal stability of the panel, and a pair of bottom cantilever connections, which support the weight of the panel. A typical response mechanism of the fastening system consists of three distinct stages: sliding with limited friction, contact with the panel causing an increase in the connection stiffness, and failure. It has been found that the capacity of the complete system is limited by the displacement capacity of the top connections, which are the most critical components. Therefore, it is better to express the capacity of the entire system in terms of displacements. Appropriate numerical models for the complete fastening system have been proposed and validated by the results of the presented experiments. The top and bottom connections were analysed separately and showed physically different response behaviours. The typical Coulomb friction model was used to describe the friction in the top connection, whereas the viscous friction model better simulated variable friction in the bottom connection. The contacts that occur when the gap for sliding of panels closes were simulated by an abrupt increase of the stiffness of the connection.