Research On Hysteretic Behavior And Design Methods Of Steel Frame With Opening On Beam Web

Steel frame structures are applied more and more widely in civil engineering because of its significant advantages. After the Northridge earthquake in the United States and Kobe earthquake in Japan, a large number nodes of steel structures did not failure in ductility, but a lot of brittle failure instead and the connection form of beam and column and its influence on seismic performance of steel frame became hot spots of research after the earthquake. The nodes with reduced beam are a new type of nodes which many people have been studying after the earthquake. The two common kinds of nodes include RBS nodes and nodes with web opening. The aim is to make the plastic hinge move outwardly through reasonable weaken of beams without significant reduction of the carrying capacity of the nodes, thereby protecting the relatively fragile node area and achieving the purpose of ductility design.Reduced beam nodes with web opening not only can make the plastic hinge move outwardly and cross the pipelines conveniently, but also can meet the functional requirements. Therefore, this paper focus on the simulation analysis of reduced beam nodes with web opening and frames, the main contents include the following four points:(1)Mechanical performance for T type rigid nodes with opening on beam web will be analyzed by using the finite element software ABAQUS. Based on the existing test data, constitutive model of the material can be selected and three-dimensional finite element model of T type rigid nodes can be built. Then the correctness of the finite element model will be verified through the comparison with the experimental data.(2)Mechanical performance for T type rigid nodes will be analyzed based on the parameters of weaken radius, the distance from weaken center to column end and the type of weaken. The damage form of specimens can be grasped, and then the change regularity of plastic hinges and nodes performance can be mainly studied according to the type of weaken beam end, the location and the shape.(3)Three-dimensional finite element model of double steel frame with reduced beam nodes with web opening can be built based on the parameters of axial compression ratio, weaken radius, the distance from opening center to column end. Static simulation analysis is conducted and monotonic loading- displacement curve, deformation and stress distribution are achieved, then the regularity and position of plastic hinges appeared are inspected.(4)The hysteretic performance analysis of double steel frame with opening on beam web will be carried out. The hysteretic, energy dissipation capacity, skeleton curves and other seismic performance indicators of steel frame can be obtained. The stress nephogram of steel frame can be viewed and the distribution of plastic hinges and collapse mechanism can be analyzed.Based on the above analysis, seismic measures and design suggestions can be put forward for the steel frame with opening on beam web end, which can provide a reference for actual engineering design.