Seismic Failure of Typical Curved RC Bridges in Wenchuan Earthquake

Reinforced concrete (RC) curved bridges suffered severe damage, or even collapsed, in the 2008 Wenchuan Earthquake. A field survey of the seismic performance of RC curved bridges was examined. Probable causes of the damage patterns to RC curved bridges - including Baihua Bridge and the ramp bridge of the Huilan interchange - are presented and analyzed in this paper. The main failure was pure shear failure or shear-flexural failure of the pier columns. Damage to bearings and expansion joints was another common failure pattern. Lessons learned from the damage to RC curved bridges in this earthquake and the recommendations on the seismic design of RC curved bridges are presented involving: ductility of bridge columns; design of curved bridges; and, design of bearings and devices preventing girders from falling down. Suggestions for the future seismic design and retrofitting of RC curved bridges in moderate-to-severe earthquake areas are also presented.