Many buildings have been built over active faults. Surface faulting as a main effect of earthquakes can cause damage such buildings. Properties of material over bedrock affect the pattern of rupture propagation through deposits and the width of the rupture zone on ground surface. Several researchers have primarily studied fault rupture propagation patterns on single-layered granular soil; however, natural geologic deposits are rarely homogeneous and uniform, but mostly consist of different layers. In this study, centrifuge model tests were conducted to investigate the patterns of reverse fault rupture propagation through single and double-layered soil stratum. It was observed that the soil type and sequence of layers affected the fault rupture propagation pattern as well as the surface rupture zone. The results show that the width of deformation zone tends to decrease in stiffer soil in compare to softer soil. These findings may help to produce a framework for predicting the occurrence and geometry of surface fault rupture zone that, can help us to define a setback zone, which is a major concern in building codes.

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