Effect Of Interface Condition On The Mechanical Behavior Of CFST Arch Bridge

Truss concrete filled steel tubular arch bridge main arch rib is mainly composed ofbottom chord, bracing, CHS, with strong integrity, bending rigidity, good ductility, itsmechanical characteristics are similar to single pipe concrete filled steel tubular arch bridge.truss arch bridge mainly upper and lower two round steel tube concrete stress, and the bar isinfluenced by the axial force is given priority to, can give full play to the characteristics of thematerial, the soil actual is being increasingly widely used, Yet for this kind of structure designtheory and experimental study is less, has yet to be further research.In order to study different interface conditions on the mechanical performance of trussconcrete filled steel tube arch bridge, this article first to the limb lattice type circular crosssection concrete filled steel tubular truss structures is researched, from two aspects discussesthe interfacial bonding properties of concrete filled steel tube truss structure on its bearingcapacity. Basic parameters on the one hand, based on the initial debonding of limb lattice typeconcrete filled steel tubular truss structures with circular cross section is researched, on theother hand to separation gap as the basic parameters for the two of the truss componentloading test. On this basis, using ABAQUS finite element analysis software, to verify thecorrectness and feasibility of the numerical simulation, finally established the model ofconcrete filled steel tube arch bridge, the parameters are analyzed.This paper made the following several aspects:(1)In order to discuss the concrete filled steel tubular truss structure interface debonding effect on the mechanical properties of steel tube concrete bonding interface, design andproduction of concrete filled steel tubular truss beam specimens, then the bonding interfaceof the concrete filled steel tubular truss beam specimens have been dealt with varyingdegrees of interface, respectively for the steel tube wall wipe grease and shaving processingcontrast experiment, study its effect on the properties of steel tube concrete interfacebonding.(2)To investigate different separating gap ratio on concrete filled steel tube trussstructure, the influence of the bonding interface, this paper carried out considering fullybonded and the separation gap at a rate of20%of comparative test, makes a research onseparation gap ratio concrete filled steel tubular truss structural ultimate bearing capacity, theinfluence of structure stiffness.(3)On the basis of test research, this paper discusses the load-deformation of circularconcrete filled steel tubular truss relationships were studied, the whole process to establishthe nonlinear finite element calculation model of concrete filled steel tubular truss, throughtypical test and the results of comparison and analysis, validate the rationality of the model.On this basis, the author of girder specimens in the bending process of load-deformationrelations under the state has carried on the analysis, further study of the composition of eachbar truss beam on the stress and strain distribution and the change rule in the process ofstress.(4) After a series of reliable data and general laws, single pipe arch rib is established andthe finite element calculation model of dumbbell arch rib, using ABAQUS software tosimulate the effects of parameters on its mechanical performance calculation results showthat the basis of single circular tube arch rib of bearing the effect is not obvious, but theimpact on the dumbbell arch rib is bigger.