Applied Mechanics and Materials Vols. 256-259

Abstract: In this paper, the elasto-plastic dynamic analysis on dynamic failure behaviors of steel double-layer latticed cylindrical shells with three circle centers used in a gymnasium is carried out under EL-centro wave with SAP2000, and the appraisal results on their anti-failure performances are presented under strong earthquake action based on the plastic-hinge theory. In the analyses, the geometric and material nonlinear effects are considered simultaneously based on the plastic-hinge theory. The plastic development level of the rod, the deformed shape and the failure type and the ductility are estimated by plastic hinge principle. The results show that the failure model of the structure under the earthquake wave action is complicated. Firstly the middle of the lower chord destroyed due to lack of tensile strength, then the stiffness of the integral structure degenerated, and ultimately lost its bearing capacity. Therefore, this structure has a high bearing capacity and good ductility.

Abstract: As an important carrier of electricity power, ACSR is a principal part of power system and is directly related to the transmission line reliability and safety. ACSR strands stress analysis is the foundation of studying ACSR mechanical properties. In this paper, finite element method is used to analysis the Acsr strands stress. The structural characteristics of Acsr is considered and the complete Acsr model is created by ansys to simulate the distribution of stress and strain under appropriate boundary conditions. The Conclusions are drawn that both the state of strands stress and the stress concentration level are related with its structural properties. The strands of out layers bears more stress and firstly comes into plastic strain. The results of the research is helpful to the further study of ACSR strength and conductor fatigue life.

Abstract: To study the temperature field changing regulation of hydration heat and control concrete cracks caused by great temperature difference in the construction of hollow-thin pier, testing the temperature field of the high and hollow-thin pier of Cha Jiugou Bridge and it got changing regulation of the temperature. The finite element analysis on the pier was also carried out and the temperature stress contours and curves of the hydration heat of the concrete are obtained. It can be seen that the outer surface and the center of the pier are compressive within 10 hours in the pouring early. With the temperature difference, the center generates the compressive stress, the surface generates tensile stress.

Abstract: According to tests of 8 T concrete beams with HRB500 steel bars as stirrup, the shear behavior of beams was researched under uniform load, and the influencing factors of diagonal crack width were analyzed, such as the different concrete strength, stirrup spacing and the welded wire fabric. Experimental results show that concrete beams with HRB500 steel bars as stirrup show similar behavior to the beams with conventional stirrup, and the stirrups yield can be achieved which meets the requirement of shear behavior in structure. In addition, the welded wire fabric can be used as one of the new kinds of reinforcement to control diagonal crack width.

Abstract: This paper brings forward a new kind of specially-shaped column and its end-plate connection joint with H-section beam. The static loading and cyclic loading simulation tests of the joint are carried out using the finite element software. Under static load, the moment-rotation curves with different parameters are obtained, and then the effects of those parameters on the initial stiffness and the ultimate moment and the stress distribution of key positions of the joint are discussed; under cyclic load, the moment-rotation hysteretic curves are obtained and mechanical behaviors of the basic test specimen are comprehensively analyzed. The results indicate that the joint possesses not only reasonably high initial stiffness and ultimate capacity, but also excellent ductility and energy-dissipation capacity.

Abstract: The tensile and compression performance and shear performance should not be changed when using variation principle to analyze shear lag of box beams. So based on transformed-section method, the section composed with steel and concrete can be transformed to one section made of supposing material. The shear lag of supposing section is analyzed to calculate the distribution of normal stress, then according to the constitutive relation of steel and concrete, the stress of actual section can be obtained. At last, the formula of normal stress in flange slab for reinforced concrete box girder is given.

Abstract: Based on the state-of-the-art of the research on connection of steel coupling beam to shear wall, The steel coupling beam has satisfactory seismic performance which is better than reinforced concrete coupling beams and composite coupling beams. In this paper, the existing research results were summarized and some views were put forward. It was useful to develop a seismic design method for hybrid coupled walls in China.

Abstract: In order to research the calculation method of shear capacity for fire-damaged reinforced concrete (RC) beams, the reason of drop of shear capacity was analyzed from material properties and transfer mechanisms of RC beams after fire. Formulas of shear capacity were suggested for fire-damaged RC beams. Based on test analysis, the values of reduction factors of shear capacity were proposed under concentrated load. The results show that suggested calculation method is capable of predicting shear capacity of fire-damaged RC beams exactly. The values of reduction factors of shear capacity need further experiments research.

Abstract: The paper presents numerical analysis on steel-encased concrete filled prefabricated FRP (fiber reinforced polymer) tubes short column through the finite element analysis software ABAQUS and verifies simulation results compared with experimental results in order to investigate the mechanical behavior of the composite column under axial compression. Based on the correct simulation results, the full-range study combined with the concrete, steel and FRP tubes of stress distribution, the mechanical performance of the column are studied in this paper. The research shows that the stress-displacement of composite column calculated in the paper can be divided into three stages, namely, elastic stage, elastic-plastic stage and failure stage.

Abstract: In order to study the impact of the measured defects on the structure and properties of steel tubular scaffold, the stochastic finite element theory is used to study the different effects of different defect structure.To accord to the random sampling method, Nine five projects under construction fasteners scaffolding works pipe is measured.In the the live 6m and 3m φ48 × 3.5 specifications 748 pipe wall thickness, diameter, initial bending raw data is random sampling tests. Article establish a structure commonly used rod defects random distribution of pipe wall thickness, diameter and initial bending deviation and the parametric statistical information,through the use of the probability statistical theory and methods,excluding abnormal data. The article explores and studies fasteners scaffolding structure in different fastener tightening torque (30N • m, 40N • m, 50N • m), ideal initial geometric imperfections 3L/1000, and the measured rod defects and defectof the structure carrying capacity and impact analysis, by means of analysis software, the use of the consistent defects modal method and random defects modal method. The results of the analysis show that the pole bending defects affect the carrying capacity of steel scaffolding structure defects . Measured defects affect the steel scaffolding structure, leading to serious security risks. It is necessary to strengthen the control rod defects. The results provide reliable information for the design and construction units.