抄録
Deteriorated truss bridges have caused catastrophic problems in the USA and Japan. Progressive collapse analysis is carried out for three continuous steel truss bridges using large deformation elastic plastic analysis. It is intended to clarify how the live load intensity and distribution affect structural safety and ductility for these two truss bridges. Although the collapse process is different depending on live load distribution and length of the spans, the truss bridge collapses due to plastic buckling or elastic buckling. The final load amplification coefficient k is over 5.4 in all cases. It is found that ductility of Model Bridge-B with span ratio of 1:1.3:1 is larger than that of Model Bridge-A with span ration of 1:2:1.
