英文摘要 |
There are many reasons for the failure of a crossing bridge. Domestic and international studies have pointed out that one of the main reasons is scour events. In existing bridge design codes, the scouring effect is not considered as a load effect. When considering multiple-hazard reliability design, engineers face problems with load and resistance factor design(LRFD) that do not consider the scouring effect as a load. This study offers a novel approach of transferring the scouring effect into a load pattern and applying load combinations, yielding a more direct design method. This research continues on from previous results, starting with the concept of an equivalent scour load. We propose two applications of equivalent scour load: one is building a scour fragility curve, the other is calculating the load factors of multiple-hazard LRFD. The objective is to help engineers to evaluate and design a crossing bridge with scour events. We use a Monte Carlo method to simulate hazards and evaluate bridge failure probability with conditional probability. Finally, we obtain the scour fragility curve in order to calculate the load factors in multiple-hazard LRFD through reliability analysis. After developing a scour fragility curve, engineers can quickly obtain the failure probability versus scour depth. The load factor of the multiple-hazard LRFD can be used in the design of a crossing bridge, which will make the design procedure smoother. |