Static Performance Of High-Water Rapid-Setting Material-Filled CHS T-Joint Under Compression Loading

Along with the formulation of the 13 th Five-Year Plan, national policies support the development of steel structure industry and steel structure application obtained the unprecedented promotion.At the same time, The node stress of the whole structure are more demanding than ever before.In order to ensure the bearing capacity of tubular joints and avoiding excessive weight of the structure, this paper proposes a new form node that using High-Water Rapid-Setting Material to replace the traditional concrete filled in the chord.Through letting High-Water Rapid-Setting Material and chord to form a whole structure to improve the structural behavior of the node.Based on the related studying achievement,the compressed property of High-Water Rapid-Setting Material-Filled CHS T-Joint is researched by using model test method,finite element simulation method and theory analytic method.Firstly, by using model test method to contrast the differences in the performance of the three types of nodes.The test indicated that the failure mode of High-Water Rapid-Setting Material-Filled CHS T-Joint is similar to CHS T-Joint. The ductility of this node is very good and the bearing capacity of this node has a great improvement. However,comparing with concrete-filled CHS T-Joint, this form of node can reduce the weight of the structure. This paper using ABAQUS finite element to simulate the failure mode and ultimate bearing capacity, stress development of the node, and proving the validity of the finite element simulation.Then,the author modified the finite element model and studied the influence of various parameters on the node properties.The node parameters include: yf, β,τ,γ,cf.The analysis results show that each parameter have great influence on the compressive performance of the node.The node will achieve the optimal performance of the bearing performance and deformation performance as various parameters change in a reasonable scope.Additionally, This paper summarizes the failure modes of High-Water Rapid-Setting Material-Filled CHS T-Joint include: brace yield failue, brace buckling failue and high-water rapid-setting material crushing. Through the analysis of the transfer mechanism of node under pressure load,the author established the simplified mechanical model of the load,and then the author suggested the formulas to calculate the ultimate bearing capacity of High-Water Rapid-Setting Material-Filled CHS T-Joint under different failure modes.In addition,Several detailing requirements of the node also be proposed.Finally, the principal conclusions in this paper were summarized, and the topics that need to be further studied were discussed.