Influence of Foundations Type on Traffic-induced Vibration Assessment Using an Experimental/Numerical Hybrid Methodology

Prediction of vibrations in buildings due to railway traffic is challenging due to several aspects, namely the huge dimensions of the domain, the interaction between different systems, and the uncertainties inherent to the complexity of the system. Therefore, experimental/numerical hybrid prediction techniques are of great interest since they take advantage of the combination between experimental data and numerical resources. In this context, the type of foundations of a building are preponderant in the dynamic soil-structure interaction effect and may have an influence on the accuracy of the hybrid prediction. The presence of the building foundations could significantly modify the response of the local sub-soil of the building. This fact makes that the prediction of vibrations in buildings becomes a complex wave propagation problem. As different types of foundations behave differently, they lead to different dynamic responses in the structure for a prescribed incident wave field. Therefore, dynamic soil-structure interaction coupling is also affected by the building’s foundation type. In order to investigate this phenomenon, this paper studies the influence that the consideration of three different foundation typologies, shallow, slab and deep foundations, have on the prediction of railway-induced vibrations on a building using an experimental/numerical hybrid methodology. A comparison is made between the results obtained through the hybrid method and the numerical results obtained through a numerical model based on the full system.