Papers by Author: Yong Liu

Abstract: The force behavior of outer annular-stiffener type steel castellated beam (OATSCB) - concrete filled steel tube (CFST) is analyzed, and the feasibility of this kind of join is discussed. The loading process of the joint is simulated by using finite element software. By analyzing the hysteretic loops, skeleton curves, energy dissipation coefficient, equivalent viscous damping coefficient and ductility coefficient, the bearing capacity and seismic performance of this type of joint is studied. Before simulation, the validity of the simulation method is verified by using the previous experiment data of outer annular-stiffener type steel beam (OATSB) - CFST. It shows that the results from the finite element simulation method and the experiment are similar to each other, and the hysteretic loops is plump , the energy dissipation coefficient, equivalent viscous damping coefficient and ductility coefficient of this type of joint are high. It can be seen that this type of joint has good mechanical properties, and is easy to realize the yield mechanism of strong column weak beam.

Abstract: during the process of fitting or synthesizing near-fault ground motion，parameters of the equivalent velocity pulse need to be decided based on seismic records．Thus, it is a key problem that how to identify these parameters from the records．Pulse period and pulse peak velocity are important parameters in the equivalent velocity pulse models．In this study，various methods on identifying these parameters are reviewed．It is shown that all the existing methods have limitations，especially for the irregular seismic records．Finally，problems need to be further studied is pointed out.

Abstract: With the increasingly sophisticated theory of concrete filled steel tube (CFST) and its’ wide application, how to make the CFST steel beam-column joints (SBCJS) becomes one of the key problems in research. According to the relevant references in and abroad, types and research done on CFST SBCJ are introduced, including outer annular-stiffener type, Inner stiffening ring type connection with anchorages type, beam integral breakthrough type etc. Finally the key problems need to be further studied are promoted.