Bridge Progressive Collapse Vulnerability

For important structures, it is increasingly required that catastrophic failure of the entire structure be prevented. Failure of an element due to an accidental event must not result in progressive collapse of other elements or of the whole structure. Studies to comply with this requirement for a bridge of numerous spans are presented. Dynamic analyses with experimental verification show that inappropriate choice of the statical system can produce a structure vulnerable to progressive collapse. The study indicates, for the considered bridge, a load case that must be considered in the design of sections to prevent progressive collapse.