Effect study of initial stress on bearing capacity of dumbbell-shaped CFST bridge

Steel tube may produce initial stress under the process of the steel tube concrete arch bridge construction, how old effect does it to ultimate load of stability of arch rib, so far there is nobody bringing forward the data studying concretely. According to construction steel tube concrete arch bridge, The calculation method of spatial solid-beam element which contains the initial stress was introduced to analyze the effect of initial stress on the bearing capacity of dumbbell-shaped CSFT arch bridge. According to this method, a computing program was introduced and influence of initial stress ratio, sectional steel ratio and spans were studied based on these. And result indicates that initial stress existence makes the limit bearing the weight of arch rib force lessening , maximal reach to approach 18%, In addition, a formula for the bearing capacity of dumbbell-shaped CFST arch bridge which considered the effect of initial stress was proposed.