Study On Dynamic Behavior Of CFDST Pier Under Lateral Impact

The new steel-concrete composite structure called CFDST (Concrete-Filled Double Skin Steel Tubes) is improved basing on the CFST. This structure carries out plenty of merit, such as cross-section and great bending stiffness, which helps it get more and more attention in engineering practices. CFDST is commonly used in piers, offshore platforms, columns and other high-rise buildings to withstand the pressure of structural as configurations members. This structure used in the process is inevitable to being hit by vehicles or shops, and the impact is such a serious threat to people’s lives and property.Currently, research on CFDST mainly focuses on static properties, such as axial compression, pure bending, bending and other properties; the research of pier’s crashworthiness focuses on the tests theoretical calculation and other means to forecast the impact force, or the devices to avoid collision damage caused by ships. This paper study on the pier of CFDST, analyze the carrying capacity of this structure, for further research of the dynamic behavior of CFDST Pier under lateral impact. In this paper, the work was commenced as follow:1) The lateral impact test carried out on the test machine named DHR9401in Taiyuan University of Technology. Global and local deformation of the specimens during the test was observed, the impact test piece (F), the strain (e), the deflection(Δ) time curve was recorded. 2) Apply ABAQUS to establish finite element model to simulate the test process. The simulation and experimental results were compared to verify the validity of the finite element model. On the basis of the validity, analyze the whole process of the impact and the relevant parameters, specially explain the empty heart (χ) impact on the dynamic response of CFDST.3) Considering the engineering applications of CFDST pier, using ABAQUS finite element to establish a vehicle collision model, analyze the dynamic behavior of CFDST Pier under lateral impact. In the model, the car was given different gravity and velocity. According the damage level and the performance level of the CFDST pier, explain the impact force (Demand) vehicles produced and piers own carrying capacity (Capability).The proposed method of determining the vehicle impact force (Demand) and piers own carrying capacity (Capability) provide more reference for the design piers and other vulnerable members.