Optimal Target Reliability of Bridge Considering Life Cycle Cost

摘要

This study accounts for presenting a methodology to determine the optimal target reliability of bridge, using a concept of Life-cycle cost (LCC). Relationship between the reliability index and the estimated LCC is analyzed to find the optimal target reliability. The analysis reveals that the LCC of bridge has great influence on target reliability especially when the bridge has greater number of lanes with longer span. It is also ascertained that higher target reliability is required for minimizing LCC, when the number of lanes or ADT increases. When the optimal target reliability is determined, target reliability adjustment has been performed by using governing limit state equation. The analysis result showed that target reliability index can be adjusted consistently within the appropriate ranges by modifying resistance factor in limit state equation.