Services provided

• Vibration analysis, cause determination
• Retrofit recommendations

Identified the cause of vibration and developed strengthening and retrofit alternatives. Based on our recommended alternative, the bridge was added two strong longitudinal tie beams and the bridge vibration issue has been resolved. Its span length, rise, and rise-to-span ration are 446.2 ft, 88.6 ft, and 1/5 respectively. The roadway width is 30 ft. The shape of the arch rib is a second-order parabola. The bridge consists of two ribs which are hinged at both ends. The bridge deck is supported by thirteen stringers of reinforced concrete T-beams which are simply supported on seventeen reinforced concrete floor beams. The entire bridge deck system is supported from the arch ribs by hangers. The bridge vibrated significantly after it opened to traffic. Part of the retrofit method was presented in 2011 IABSE Symposium and in TRB 2015 Annual Meeting.