Applied Mechanics and Materials Vols. 405-408

Abstract: Top-and-seat angle connection is a type of semi-rigid connection, usually used in steel frame. The initial stiffness of top-and-seat angle connection is an important index for steel frame design. The article studied the initial stiffness of the connection considering the influence of column flange. The deformation and mechanical characteristics of top-and-seat angle connection were analyzed using ANSYS. According to the results of FEM analysis, theoretical models of the connection and the initial stiffness formula of connection were proposed. For verifying the correction of the formula, 8 FEM models were built and initial stiffnesses were calculated correspondingly. The formula proposed by the article agreed well with the results of the FEM analysis. And it proves that, the initial stiffness formula of top-and-seat angle connection proposed herein can be used in the design.

Abstract: This paper investigated the strength, peak-to-peak stiffness and energy dissipated capacity of coupling beam with diagonal headed-bars. Test variable included the replacement ratios of diagonal headed-bars. The results show that specimens HB 30, and HB 50 using headed bars for concrete confinement sustained corresponding peak-to-peak stiffness and cumulative dissipated energy in comparison to specimen CON.

Abstract: Based on the cost of concrete and longitudinal reinforcement of reinforced concrete rectangular section single-reinforced Beam, the authors take as the variable the reinforcement ratio and the valid height of the rectangular section, and then derive the economical reinforcement ratio and planned height for the reinforced concrete rectangular section single-reinforced Beam. The research result has important practical meanings for reinforced concrete rectangular section single-reinforced beam.

Abstract: Tensioned membrane structures are pre-stressed membrane structures that are appropriate to be used for long span application. Tensioned membrane structures must depend on their shape and internal pre-stress alone to achieve stability and to carry the loads. Some of the largest stadiums, airports, convention halls and commercial places are tensioned membrane structures. It is essential to perform shape-finding analysis while dealing with tensioned membrane structures. In this study, shape-finding analysis is carried out using computer program for stress analysis which is based on theory of nonlinear displacement method. Shape-finding of membrane surface bordered by Egg has been investigated. In this study, the possibility of adopting the form of Egg as surface shape for tensioned membrane structure has been studied.

Abstract: This paper introduces the characteristics and practicability of the honeycomb beam and analyses the mechanical behavior. Based on the vierendeel truss theory, the normal stress calculation method of the rectangular hole honeycomb beam is discussed, and the calculation formula is deduced. Finally using the derived formula, the paper calculates the normal stress of the rectangular hole honeycomb beams with different parameters, and analyses the influence of the opening rate and the hole spacing on the strength of honeycomb beam by comparing the same section of solid web beam, thus, provides reference for design of steel honeycomb beam.

Abstract: In order to provide evidence for optimization design of directly buried heating pipeline tees, finite element models of tees with different ratios of branch-main pipe diameters had been established and simulated by structure analysis soft ANSYS. The change law of maximum equivalent stress values in pipe-nozzle intersection area had been obtained at same temperature, pressure loads and displacement constraints. The results show that maximum equivalent stress values of stamped tees are less than welded tees with same specifications. And stamped tees with lager fillet radius and local wall thickness can effectively decrease maximum equivalent stress values of pipe-nozzle intersection area.

Abstract: Through the finite element simulation to study the local stability of the circle-castellated beams, reasonable finite element model was established using finite element software and in-depth analysis of the local stability of the circle-castellated beams on the basis of the castellated beams shear performance test. The same span of the circle-castellated beams, deformation stability performance under two point loads simulation, got deformation form of castellated beams under different pitch of holes, opening ratio, stiffener thickness, depth-thickness ratio. The local stability properties of the same span of the circle-castellated beams are directly related to opening ratio and web depth-thickness ratio changes, which has little effect with the change of hole spacing, stiffener thickness. Using the appropriate opening ratio, web depth-thickness ratio plays an important role on improving the local stability of web under the shear force and the bending moment.

Abstract: Form-finding of fabric surface bordered by Oval has been investigated. In this study, the possibility of adopting the form of Oval as surface shape for tensioned fabric structure has been studied. The combination of shape and internal forces for the purpose of stiffness and strength is an important feature of fabric surface. For this purpose, form-finding needs to be carried out. Nonlinear analysis method has been used for form-finding analysis of the fabric in the form of Oval.

Abstract: Basic principles of the modal analysis are introduced. Model analysis of an oxytropis tower which is in an actual transmission tower system is carried out. Rationality of the modal is checked by results of the vibration periods. Meanwhile, analysis of vibration types of transformation and rotation under seismic action is also carried out, in order to provide reference data for further elastic-plastic analysis.

Abstract: The concrete simple supported beams were strengthened by an innovative device mainly includes oblique screws and linear CFRP tendons. A static experimental study and finite element analysis were conducted to research the flexural capacity and stress changes of CFRP tendons of strengthened beams, and the contrastive analysis was explored between finite element calculation results and test results. The results indicate that the strengthen system can significantly improve the flexural capacity of concrete beams, there is basically a linear relationship between the stress increment of CFRP tendon and the deflection of midspan section, and the finite element calculation value is in agreement with the test results. Based on this, the stress of concrete near holes was analysed using finite element method (FEM), which can provide a reference for practical engineering application.