Advanced Materials Research Vols. 594-597

Abstract: Through the uniaxial compression test, the mechanical properties of different placements of iron wire cement mortar, e.g. compressive strength and elastic modulus, were studied, and the mass ratios of cement, sands and water influencing the mechanical properties were put forward, which provided the experimental results for reference for the wide use of the iron wire cement mortar material. From the study it is gained that: (1) The best placement of the iron wires in cement mortar is horizontal. (2) The best mass ratio of the cement, sands and water is 1:4.70:0.81.

Abstract: Abstract. In this paper three-way double-layer space grids structure is assumed as equivalent sandwich plate, and has been analyzed by the non-traditional theory of plate with three generalized displacements, in which shearing deformation is considered. Based upon the split rigidity method, static analysis and natural vibration analysis of three-way double-layer space grids structure has been studied. The formulas for calculating internal forces, displacement as well as natural vibration frequency are given out. The comparison with finite element method and equivalent sandwich plate method shows that the formulas in this paper are not only simpler than other simplified methods but also of high accuracy.

Abstract: A calculation model about failure mode and ultimate bearing capacity of steel truss coupling beam is proposed based on compatible distortion and balance conditions, second-order effect, elastic-perfectly plasticity and strain state about eight specimens when these specimens fail under low cyclic reversed loading. And then this model is applied to analyzing influences of height, span and chord stiffness on bearing capacity of truss. Some valuable results are obtained such as advantageous range of span-to-height ratio and influence laws of chord stiffness on ultimate capacity.

Abstract: Ductility of six L-shaped concrete-filled steel columns with binding bars and one without binding bars were discussed based on the experimental study. A new method based on material properties instead of experimental data was proposed to estimate the ductility of six L-shaped concrete-filled steel columns with binding bars and one without binding bars. Comparison between ductility coefficients based on experimental data and the calculated values by the proposed method shows good agreement.

Abstract: The relevant specifications in China make the relevant regulations to guarantee the stability of the shear wall and provide the check formula. This paper discusses the rationality of the calculations on the shear wall stability from the perspective of the reliability index, and calculates the reliability index in the state of the shear wall’s instability limit by means of JC method, the result shows: the current regulations can not guarantee the requirement that the reliability index of the shear wall is not less than the target reliability index. Based on the target reliability index, load partial coefficient and load, geometric dimension probability statistical parameter, this paper uses JC method to make inverse operation, calculates the shear wall stable resistance force partial coefficient under four types of load effect combinations, and analyzes the influence of load effect ratio, thus getting the shear wall stable utmost limit load best resistance partial coefficient.

Abstract: The mechanical properties, such as yield strength, modulus of elasticity of steel cable and its mechanics model were obtained based on the mechanical properties of steel cable under the high temperature test results. Nonlinear finite element numerical analysis method was established based on the time integral effect considering. The characteristics of temperature field distribution, displacement and stress are discussed. The reuslts show that: BSS has better spatial work performance, the weak area of the structure is near the far side, the main reason of large deformation is the reduce of stiffness and strength.

Abstract: Based on the triple shear unified yield criterion and the ultimate equilibrium principle, the ultimate pullout force of prestressed cable is studied. The ultimate pullout force of prestressed cable is related to the rock type, the shapes of rapture surface, grouting pressures and compressive strength of rock, etc. The results show that the intermediate principal stress effect parameter b have influences on the ultimate pullout force of prestressed cable. With the increase of the intermediate principal stress effect parameter b, the ultimate pullout force of prestressed cable increases too. When the grouting pressure increases, the ultimate pullout force of prestressed cable increases also.

Abstract: This paper treats the impact force and the displacement of the lamella single-layer reticulated dome and the suspendome under axial impact loading using non-linear finite element techniques. The influence of loading parameters and the cable force of the suspendome on the impact response is investigated using validated numerical models. Results are quantified in terms of important impact response parameters and indicate that the peak displacement of the lamella single-layer reticulated dome and the suspendome can be clearly divided into four stages with time , and time history curve of the impact force can be divided into three stages.

Abstract: As the result of great changes occurring to mechanical properties under high temperature (fire) conditions, steel structures will soon lose the strength and stiffness and lead to structural damage. Through analysis of the steel structure fire resistance design methods under the conditions of high temperature (fire), this article explores the most used fire protection methods in steel structures—brushing or painting fire-resistant coatings, studies the fire-resistance theory of steel structure under fire conditions; in addition, the author proposes the reasonable thickness of the steel structure fire retardant coating of fire-resistant design through design examples.

Abstract: The most common analysis methods of complex high-rise buildings are the response spectrum analysis, elastic time history analysis, pushover analysis and etc. Meanwhile, for the analysis of those high-rises whose height is higher than 200 meters, period is longer than 4 seconds, the dynamic nonlinear analysis would be more accurate. In this paper, the dynamic nonlinear analysis was executed in use of the Perform-3D program. The results show that the maximum top displacement can meet the national codes; most tie beams and the frame beams of the upper structure yielded in the IO~IS stage and parts reached the CP stage; both the laminated columns and the frame columns had a good performance on the shear behavior; and it is also proposed to strengthen the reinforcement at the reducted storeys. By all these above, it can be judged that the structure reached the codes’ seismic performance objectives.