Abstract:
In order to study the interfacial bonding performance of self-stressing concrete filled steel tube, the relationship between temperature change of core concrete and radial self-stress of core concrete and circumferential self-stress of steel tube was deduced according to the balance of force. The finite element analysis model considering the interfacial bonding performance of concrete filled steel tube was established by taking the content of expansive agent as a variable on the basis of existing test data in literature, and the interfacial bonding performance of concrete filled steel tube was simulated by heating up the core concrete, the comparison of the simulative. The experimental results indicate that the method of heating up the core concrete can simulate the interface bonding performance of self-stressing concrete filled steel tube effectively and truly, on this basis, numerical analysis of factors affecting interface bonding performance was carried out by changing the self-stress level by heating and adjusting the diameter-thickness ratio. The results show that the interfacial bonding performance of concrete filled steel tube can be effectively improved by increasing the self-stress and reducing the diameter-thickness ratio. The comparison between the simulative and theoretical values shows good agreement.