The Research On The Behaviors Of Concrete-Filled Steel Tube With Gaps Under Load

Because of their advantages such as longer span, higher capacity, less weight and being convenient for construction etc , concrete-filled steel tube (CFST) arch bridges develop rapidly in china in the recent years. Along with the increasing of the span, people are more concerned about the gaps in the interface between the core concrete and steel tube.A experimental study was carried out to analyze the influence of the gaps on the behaviors of the specimens.(1) 3 specimens were axially loaded. Through the results of the experiments, the yield strength , the ultimate strength, the behavior of the core concrete were studied. Besides, the rigidities of the specimens were also reseached.(2) 3 specimens were curved. The relationships of the load-strain, Moment curvature, load-deformation and the behavior of the core concrete were also studied.(3) 9 specimens were eccentrically loaded. The influence of gaps on the yield strength, ultimate strength, the deformation and the load-strain relationships were studied. Then, the core concrete's behavior was also analyzed.(4) the ultimate strength of all the eccentrically loaded columns was calculated and the divergent values between the theoretical results and the experimental results were less than 10%.(5) At last,the stability of WuXia Bridge was analyzed by employing ANSYS. Two finite element modal were refered and the results were compared.