Isolated soil mass at foundation for mitigating seismic risk

The installation of passive structural systems to protect existing buildings from seismic risk is very common, yet it can be expensive and is not always feasible in the case of valuable buildings. It may affect the integrity of structures of artistic or historical relevance in a way that cannot be accepted in the light of the most recent rules of conservation and retrofitting. As an alternative, ground improvement techniques can be used to modify ground properties, in order to mitigate the intensity of shaking at ground level. This paper focuses on the case of a V-shaped barrier that may be formed by assembling inclined and partially overlapped columns of artificially softened soil to isolate a mass in the ground. The response of a single degree of freedom founded within the isolated ground mass is then studied by way of finite-element analyses and the results are commented on