Application on bearing performance of concrete filled steel tube arch with slip ends

Through the monitoring of the displacement of the middle across section and the different slip amount in the concrete filled steel tube (CFST) arch and arch foot,which 6 points fixed at both ends under the condition of uniform loading,as well as the strain and the ultimate bearing capacity of outer steel pipe and inner core of concrete which combined with ABAQUS for simulation analysis of bending process with cohesive elements as the main research meth- od in the constitutive model of concrete. This finite analysismethod uses the three-dimensional numerical simulation which displayed accurately in the whole progress of uniaxial compression experiment in the micro aspects. The actual morniting and experiment results shows that compared with the two fixed ends of the CFST arch which damaged by the triple action of pulling、pressing and bending,some cracks appeared on the process of arch slip. When the loading in- creasingly,the presence of cracks leads to concrete volume expansion,and then make the steel tube drum package. In the range of a certain amount of arch foot slippage,the middle section of core concrete occurred bottom tension and top compression,the bending increased with sharp of the test block span and arch foot,the bearing capacity of steel tube reinforced concrete circular arch is decreased with the increase of the amount of slip of arch foot. Through theoretical deduction,numerical simulation and indoor test,the results of field monitoring can be seen which means the displace- ment of the middle section of the CFST arch was two times of the amount of slip on both arch ends. After reaching the ultimate load the yield of concrete filled steel tube (CFST) circular arch is one of the hoop action failure of the con- crete.