Simplified theoretical approaches to earthquake fault rupture – shallow foundation interaction

Construction of buildings in the proximity to seismically active faults is restricted by clause 4.1.2 of Eurocode 8 Part 5. However, there is no clear definition of the safe distance to fault, and the uncertainty related to the location of main and secondary traces of rupture for a future event can prevent the reduction of fault-breakage related risks to acceptable levels. The diversion of the surface trace of rupture by massive structures seated on thick soil deposits can be beneficial for the risk reduction. The scope of this study is first to revise previous theoretical approaches for providing simple engineering criteria for the diversion of the surface breakage of fault rupture for shallow foundations and, secondly, to extend them to treat the case of drained soils subjected to normal or reverse fault. The applicability of these criteria, which essentially provide minimum values for the weight of structure depending on the thickness of the surface soil deposit, is discussed through comparisons with the experimental results.