Non-linear seismic dynamic response of curved steel bridges equipped with LRB supports

The susceptibility of horizontally curved steel highway bridges to seismic damage increases substantially when subjected to Level II Earthquake Ground Motions. The growing need for safer bridges has stimulated the replacement of vulnerable steel bearing supports with seismic isolation devices. The purpose of the present study is to analyse the overall performance of highway bridges, with an emphasis on the effectiveness of seismic isolation based on Lead Rubber Bearings (LRB). The analysis of the bridges was performed on three-dimensional models using a numerical method based on the dynamic response analysis, considering both geometric and material non-linearities. The non-linear bridge models were subjected to strong ground motion records from the 1995 Kobe earthquake. The efficiency of using LRB supports on curved highway viaducts is demonstrated in this study. The results show that seismic isolation improves the seismic response of curved bridges and reduces excessive seismic damage.