Study On Influence Of Concrete Strength,grade Of Steel And Steel Ratio For Mechanical Property Of Scfst

The concrete-filled steel tubular structure gives full play to the role of steel pipe and concrete,so it has superior mechanical properties. According to the survey, most of the ordinary concrete-filled steel tubular arch bridges have different degrees of void phenomenon in china, that lower the capacity of concrete-filled steel tubular structure. Because of core concrete's expansion of self-stressing concrete filled steel tube, interior of concrete-filled steel tubular structure produce self-stressing, make the core concrete in three state of compression, and improve mechanical behavior of concrete, so, largely raise the structure's capacity. This paper mainly research on influence of ultimate bearing capacity by three factor of different steel grade, the core concrete strength and steel ratio. The following aspects are the main content:â‘ Analysis the concrete-filled steel tube working principle and failure mechanism of core concrete under three state of compression, research on the whole process of force of self-stressing concrete filled steel tube, and divide it to four stages for analysis;â‘¡By study on Simulation of ANSYS of concrete-filled steel columns under compression, we can research on the influence of ultimate bearing capacity of concrete-filled steel tubular structure by different steel. The results show that self-stressing concrete filled steel tube structures have large capacity with the large of steel type. The ultimate bearing capacity of self-stressing concrete filled steel tube would raise from 6.38% to 10.56% under the condition of the same concrete Strength but different steel type;â‘¢Combined with some experiment in certain literature and ANSYS, calculate and analyze the influence of ultimate bearing capacity of concrete-filled steel tubular structure by different strength of core concrete, and contrast self-stressing concrete-filled steel columns with that of ordinary concrete on the premise of the same steel type and different core concrete strength. Our results indicate that self-stressing concrete filled steel tube structures have large capacity with the high core concrete strength, compared with ordinary concrete, the ultimate bearing capacity of self-stressing concrete filled steel tube increase 18% on the same condition;â‘£Use ANSYS to Simulate pressure of five self-stressing concrete-filled steel columns in different steel ratio, get a conclution of relation between steel ratio and Concrete confining force. The results show that the confinement factor is in proportion to steel ratio in the same steel and concrete; with the increase of steel ratio, the ultimate bearing capacity of self-stressing concrete filled steel tube also increase, in accordance with test data; from load - strain curve, we can conclude that the higher steel ratio, the greater slope of elastic stage's curve, that means range of elastic stage increase.