Structural robustness of an RC pier under repeated earthquakes

The seismic resilience of structures and infrastructures is affected by damage accumulation phenomena, mainly related to the type of hysteresis. Specifically, pinching drives the cyclic response of several building materials, such as reinforced concrete and masonry. Structural systems affected by pinching phenomena are prone to exhibit a dramatic increment of their displacement response after multiple cycles (e.g. repeated earthquakes). The authors estimate a reinforced concrete pier's response using truncated incremental dynamic analysis by concatenating three earthquake scenarios. The authors adopted a Bouc–Wen class hysteresis model to simulate the reinforced concrete pier's cyclic response, matching its experimental cyclic response. The current analysis proved that ductility and resistance primarily drive the seismic response after a single earthquake. However, the performance after multiple earthquakes strongly depends on the pinching, degradation and drift accumulation, which are generally neglected in standard design practices.