*Article* **Seismic Response of Resilient Bridges with SMA-Based Rocking ECC-Reinforced Piers**

**Xiaogang Li <sup>1</sup> , Ke Chen 2,\*, Ji Chen <sup>1</sup> , Yi Li <sup>1</sup> and Dong Yang <sup>1</sup>**


**\*** Correspondence: k.chen@rioh.cn; Tel.: +86-138-1099-7548

**Abstract:** Post-earthquake investigation shows that numerous reinforced concrete (RC) bridges were demolished because of large residual displacements. Improving the self-centering capability and hence resilience of these bridges located in earthquake-prone regions is essential. In this regard, a resilient bridge system incorporating engineered cementitious composites (ECC) reinforced piers and shape memory alloy (SMA) energy dissipation components, i.e., SMA washers, is proposed to enhance its resilience when subjected to strong earthquakes. This study commences with a detailed introduction of the resilient SMA-washer-based rocking bridge system with ECC-reinforced piers. Subsequently, a constitutive model of the ECC material is implemented into OpenSees and the constitutive model is validated by test data. The working principle and constitutive model of the SMA washers are also introduced. A series of dynamic analysis on the conventional and resilient rocking bridge systems with ECC-reinforced piers under a suite of ground motions at E1 and E2 earthquake levels are conducted. The analysis results indicate that the resilient rocking bridge system with ECC-reinforced piers has superior resilience and damage control capacities over the conventional one.

**Keywords:** seismic analysis; rocking pier; shape memory alloy; ECC material; bridge engineering
