Use of V-shaped concrete element to mitigate foundation rotation for uncertain reverse faulting dip angle and discontinuity location

Abstract

This research presents the pros and cons of two previous mitigation methods to protect a building foundation from reverse fault rupture and then, for the first time, proposes a novel mitigation method, including a V-shaped concrete element under a shallow foundation, to reduce the foundation rotation caused by a fault rupture. The results of this study indicate that previously suggested methods, such as the presence of a weak wall next to the foundation or a strong inclined wall beside a weak vertical wall, are not suitable for unknown fault conditions, and the foundation rotation may be the same or worse than an unprotected foundation when the worst-case scenario of the discontinuity location and dip angle of the fault exists. The new effective approach diverts the rupture path and reduces the foundation rotation for the worst discontinuity location and fault dip angle by approximately 3.5° compared to the previous methods. In other words, where the discontinuity location and dip angle of the fault are unknown, using a V-shaped concrete element under the foundation is a more appropriate and effective mitigation method for structures. The results also show that the inclination angle of the V-shaped element is an important parameter compared to other parameters.