Experimental studies on dynamic soil structure interaction of mass irregular building supported on pile foundation in soft clay

During a strong earthquake, the structural configuration of a multi-storey building plays a crucial role in determining its behavior. Irregular configurations, whether in plan or elevation, can be a significant cause of failure during seismic events, particularly for buildings located in high seismic zones. Seismic analysis of structures traditionally assumes a fixed base ignoring the effect of soil-foundation-structure interaction. The objective of this investigation was to evaluate the seismic response of a 10-storey scaled model considering dynamic Soil-Pile-Structure Interaction (SPSI). Seismic response of scaled model of a regular and mass irregular building prototype was investigated using laboratory experiments conducted on a Shake table facility. The results showed that the SPSI system increases the lateral deflections and storey drift of the building, particularly for an irregular structure. This amplification effect is more significant under dynamic SPSI conditions than under fixed base conditions. Furthermore, the mass irregular structure displayed an increased response compared to the regular model in both base conditions. Additionally, the irregular structure exhibited an increase in the amplification of response under SSI conditions, which could potentially alter the performance level of the structure.