Seismic fragility analysis of steel reinforced concrete transfer frame with energy dissipation haunch brace

By utilizing a steel-concrete composite structure and energy dissipation technology, a kind of new transfer structure-a steel reinforced concrete (SRC) transfer structure with energy dissipation haunch brace (EDHB) was proposed to improve the seismic performances of transfer structures. The incremental dynamic analysis of SRC transfer frame without and with EDHBs was carried out and the seismic fragility curve equations of the new transfer structure were established. The influences of buckling-restrained EDHBs on failure mechanism of the SRC transfer frame were studied. The results show that the probability of exceedance of the SRC transfer frame in moderate, severe damage and collapse states can be significantly decreased by adding buckling-restrained EDHBs, and the EDHBs can become a reliable seismic fortification line. The lateral drift mechanism in the transfer story and neighboring stories of the SRC transfer frame can be avoided bybuckling-restrained EDHBs and the plastic deformation of transfer components can be alleviated. The global and local collapse of the SRC transfer frame can be prevented effectively by EDHBs.