Tian Hua Zhou

Study on Restoring Force Models of Steel High Performance Concrete Composite Structural Wall

Steel high performance concrete (SHPC) structural wall was a combination of steel and high performance concrete. They can give full play to the advantages of steel and high performance concrete and have better dynamic behavior. Several specimens of SHPC structural walls with different parameters were tested under constant axial loading and horizontal cyclic loading. The testing phenomena and failure mechanics of those walls were compared and analyzed. On the basis of theoretic formulas and testing data, the main characteristic points and the law of stiffness degradation were presented, then, the tri-linear and four linear restoring models were built and provided. At last, the calculation formulas of stiffness parameter in restoring force model at different stages of deformation were presented. The results show that the declined strength stage of skeleton curve of specimens is related to the yielding strain of boundary steel, axial load ratio and stirrup content. The restoring force model of SHPC structural wall is thus formed for the application of nonlinear dynamics analysis as well as static structural calculations.

Research on Cooperative Working Performance of Cold-Formed Steel Stud Wall - Steel Frame Structure

Research on cooperative working performance of cold-formed steel stud wall(CFSW) and steel frame(SF) was carried out by analytical method and finite element method. The practical calculation methods of shear force and horizontal displacement for CFSW - SF structure under horizontal load were presented. The superposition principle between CFSW and SF in elastic stage was verified in terms of strength and stiffness. The investigation by FEM indicates that the shear force distribution in elastic stage is in accord with lateral stiffness of CFSW and SF, the shear force distribution rate of CFSW declines along with the increasing of horizontal displacement while thar of SF increases because lateral stiffness of SF degenerates more slowly than that of CFSW.

The Study of Post-Fire Load Bearing Capacity of Steel Column under Axial Compression Exposure to one-Side Fire

The section of steel column under axial compression presents heterogeneous material and its load condition changes after experiencing fire damage of one side. Taking H-section steel column under axial compression commonly used in engineering for study object in this thesis in order to study post-fire residual load bearing capacity, the post-fire eccentric effect of steel column under axial compression exposure to one-side fire is analyzed using the method of equivalent section which considering the change of the material strength after high temperature, the influence of non-uniform temperature field on material properties and the stiffness degradation of member section. Calculation methods of the eccentricity and additional moment are proposed and further given a formula of residual load bearing capacity.

Research on Seismic Behavior of Concrete Filled Square Tubular Joints with Reduced Beam Section under Cyclic Loading

The 3D nonlinear FEM models of concrete-filled square tubular column with internal diaphragms and steel beams with reduced beam section bolt-weld joints, involving geometric, materials and contact nonlinear were founded. The results of FEM are agreed to that of tests, so we can conclude that FEM in this paper is correct. Then the bearing capacity behavior of joints under cyclic loading are analyzed, including P-Δskeleton curves, P-Δ hysteretic curves, the dissipating energy ability and destruction form. The analysis results show that the plastic hinge in the joint with reduced beam section is removed to the reduced beam region. The joints that studied in this paper present excellent ductility and dissipating energy ability, therefore, all of them have a good seismic behavior.

Decision Making on Glass Selection in Building Facade

Glass is widely used for its properties of transparency. It has been favoured by architects for the last two decades and used to deliver a distinct style of architecture. However, the conflicting performance requirements make the decision making on glass selection in building envelopes a complex process. This paper investigates the factors affecting the selection of glass used in building facade, and proposes a hierarchy of decision making to facilitate the information flow. This may provide an integrated and robust approach to reach an informed decision.

Study on Mechanical Behavior of Concrete-Filled Square Tubular Column and Bolt-Weld Steel Beam Joints with Reduced Beam Section

The nonlinear FEM models of concrete-filled square tubular column with internal diaphragms and steel beams with reduced beam section bolt-weld joints, involving geometric, materials and contact nonlinear, were established. The 3D models of beam-to-column joints with internal diaphragms by 3D solid elements are founded. The bearing capacity behavior of joints under the monotonic loading are analyzed, including P-Δ curves, the stresses distribution of beam, the dissipating energy ability and destruction form. The analysis results show that the initial stiffness of joint with reduced beam section is close to that of non-reduced beam section joint. The bearing capacities of joints with reduced beam section are lower a little than that of non-reduced beam section joint. The plastic hinge in the joint with reduced beam section is removed to the reduced beam region.

Research on Deformation Capacity Design Method of Steel High Performance Concrete Structural Walls

The cyclic loading test of three steel high performance concrete(SHPC) structural walls was conducted and the failure pattern of the structural walls under the combined effect of axial force, bending moment, and shear force was researched. Based on the experimental results, the displacement-based deformation capacity design method was proposed for SHPC structural walls. It is obtained for the interrelated relationships among the ultimate drift ratio, the axial load ratio, the characteristic value of stirrup content and the aspect ratio. It is concluded that the increasing the characteristic value of stirrup content and limiting the axial load ratio were effective means to improve ductility. The characteristic value of stirrup content of SHPC structural walls with different ultimate drift ratio and axial load ratio were proposed and the conclusion can be referred by the design of SHPC structural walls.

Experimental Study on Mechanical Behavior of Cold-Formed Steel Three Limbs Built-up Section Members

18 specimens of cold-formed steel three limbs built-up section members are tested under axial compression load in this paper. The section forms are divided into two categories: A and B. Load-displacement (P-Δ) curves and failure characteristics of specimens are obtained. The results show that: As to section A members, the failure characteristics of LC, MC and SC series of specimens are flexural-torsional buckling, torsional buckling and distortional buckling, local buckling and distortional buckling. As to section B members, the failure characteristics of LC, MC series of specimens are flexural buckling, while local buckling and distortional buckling for members of SC series.