FAILURE ANALYSIS AND RETROFIT STRATEGY OF THE CARDINAL RAÚL SILVA HENŔÍQUEZ BRIDGE DURING THE 2010 CHILE EARTHQUAKE

摘要

This paper presents a case study of the Cardinal Raúl Silva Henŕiquez Bridge that experiencedsignificant damage during the February 27, 2010, Chile Earthquake. Supported by reinforcedconcrete and steel columns with varying heights, the superstructure of the bridge consisted of22 steel girder spans with one intermediate expansion joint located at the middle of the bridge.At each end of the bridge, the bottom flanges of the girders were welded onto their bearingsteel plates that were embedded and anchored into the bridge abutment. Twothree-dimensional finite element models (global versus local) with beam and solid elements,respectively, were established for bridge response and damage process simulations. Fieldobservations indicated and finite element simulations verified that the damage was mainlycaused by the excessive seismic load of 11 continuous steel-girder spans under longitudinalearthquake loading and its eccentricity from the girder-to-abutment connection, resulting in asignificant bending effect. Parametric studies demonstrated that an effective retrofit strategycan be developed by reducing the number of continuous spans, modifying thegirder-to-abutment connection detail, and increasing the capacity of girders with enlargedbearing seats, additional stiffeners for girders, and thicker flanges and webs.