Fault Rupture Propagation in Alluvium and Its Interaction with Foundation: New Insights from 1g Modelling via High Resolution Optical Image Processing Techniques

Earthquake fault ruptures may emerge at the ground surface causing large differential movements. Fault ruptures can cause significant damage when they emerge at or adjacent to the position of existing foundation. However, the study of recent faulting events revealed that, in some circumstances, the fault-rupture emergence is affected by the presence of buildings. A 1g modelling study, as well as validated numerical modelling was conducted to investigate how reverse faults interact with strip foundations which run parallel to the fault strike. To better understand this process, we monitor displacement field in scaled model experiments using high-resolution optical image correlation techniques. High-resolution optical strain monitoring quantifies the spatial pattern of strain accumulation in our model experiments. In this paper, following the explanation of 1g model test apparatus, the steps leading to development of an image processing program are described. Afterwards, by using this tool, we investigate the interaction between fault rupture and foundation. This study confirms that fault rupture may be deviated by the foundation so that the foundation is protected from serious rotations and detachment.