Performance Analysis of Complex Cast Steel Joint in the Steel Roof of Hangzhou West Railway Station

The steel roof of Hangzhou West Railway Station is a complex spatial structure system which is the combination of grid and truss. Thus, there are many multi-pole intersection connection problems in this structure, which could be solved by the cast steel joints. Due to the large number of intersecting members and complex forces of the such joint, the analysis is difficult. In this paper, the complex cast steel joint in the steel roof of Hangzhou West Railway Station was analyzed by finite element and tested to determine the safety and reliability of the design of the cast steel joint.When the finite element analysis method was adopted, the joint was discussed under the design load and the limit load respectively, and the design load was taken as the most unfavorable load case of the joint, and the limit load was 3 times the design load. The finite element analysis results indicated that under the design load, the stress level of the joint was lower than the yield strength of the material. The maximum stress was 179.088 MPa, and the equivalent plastic strain was 0. Under the limit load, the stress in some parts of the joint exceeded the yield strength of the material, but the overall load-displacement curves were still linear. Since then, experimental studies had been carried out on the cast steel joint. A full-scale test study was carried out on this joint, and the maximum test load is 1.3 times the design load. When loading, the load force was divided into 26 levels from 0 to maximum. From the beginning to the end of the test, no obvious deformation of the cast steel joint was observed. Moreover, the data collected by each strain gauge showed that the maximum strain of the cast steel joint was 1 036×10^-6. This paper compared the test results with the finite element calculation results, and the degree of agreement was good, which showed the accuracy of the finite element calculation results. And the joint was in a fully elastic state under the design load, and the partial plasticity did not affect the overall mechanical performance of the joint. Therefore, it could be judged that the joint is safe and reliable, which could provide a reference for the design of cast steel joint in related projects in the future.