Applied Mechanics and Materials Vols. 94-96

Abstract: Direct pull-out tests were performed to evaluate the bond performance of glass fiber-reinforced polymer (GFRP) reinforcing bars in cement mortar. Specimens with different bar diameters and different grouted lengths (i.e., 5d, 10d and 15d, d is the diameter of bars) are prepared for the pull-out tests. For comparison, specimens with plain aluminium alloy bars (AAB) were tested as well. The result shows that the average bond stress between plain aluminium alloy bars and cement is much smaller than that between the deformed GFRP bars and cement; thin GFRP bars tended to have larger average bond stress; the shorter the grouted length, the smaller the maximum average bond stress. Only part of grouted length undertakes the bond stress and the length depends on the shear modulus of GFRP and the surrounding material.

Abstract: Through the detection and appraisal of two collapse accidents of steel structural buildings, the reasons of them are overall analyzed based on the design, construction and material of the steel structures. Combining the characteristics of light steel structure itself, some correlated suggestions are proposed including this kind of structure design and construction.

Abstract: Based on the low cyclic loading experiments on three interior joints with specially shaped columns, in which one of them was reinforced by polypropylene fiber in the core zone of joint, another steel fiber, the other was not reinforced, the authors compare the results in terms of damage characteristic, bearing capacity, displacement and ductility, hysteretic curve of the moment-rotation, rigidity degradation and energy dissipation. It is shown that seismic behavior of specially shaped column interior joints reinforced by fiber is improved significantly. The interior joint of specially shaped column reinforced by polypropylene fiber has a better damage characteristic and energy dissipation while that by steel fiber shows a higher yield load and bearing capacity.

Abstract: There is a serious problem of rural unsafe drinking water in china,but only it is essential for legislation to solve comprehensively.Through the analysis of the legislative background, legislative basis and legislative framework system of rural safe drinking water,the paper explores some legislative issues.Water source contaminated by industrial pollutants, agricultural pollutants, domestic pollutants, is the biggest obstacle to rural drinking water safety.Rural safe drinking water legislation have sufficiently the constitutional basis and the basic law basis. Legislative framework system is composed of drinking water source protection,rural water supply planning,project financing,operation and management mechanisms,emergency warning system, pricing system, supervision system etc. Rural safe drinking water legislation will play a significant role in solving fundamentally the problem of rural safe drinking water.

Abstract: Hero Bridge is an extraordinarily huge bride across northern branch Ganjiang River, in the city of Nanchang. Main tower adopted single column slanted pylon space twist face back cable structure. Its construction is based on double-wall cofferdam method. The paper discuss thecalculation of key step and key position for the key technology in terms of double-wall cofferdam and platform underwater construction, Which include the design of the base construction and double-wall cofferdam,steel cofferdam construction, the calculation and checking of the cofferdam and so on.

Abstract: Simplified calculation of initial stiffness of end-plate bolted connections is given in the paper. Considering the influence of the end-plate bolted connections to the internal force of the steel portal frames, the modified elastic calculation of internal force is suggestted. Comparing with the finite element calculation results of different span steel portal frames, the calculated value is agree with the finite element calculation results. End-plate bolted connections are semi-rigid connections, and the flexibility of the connections affects the behavior of the frames, the internal force of rigid frames should be modified when semi-rigid connections used. The modified elastic calculation of internal force of the steel portal frames with end-plate bolted connections is simple and has good agree with the finite element results, which can give reference to engineering design.

Abstract: This paper uses ANSYS finite element program to do the nonlinear finite element analysis on steel reinforced concrete L-shaped short-shear walls. Through applying the vertical and horizontal load on the model, three typical stages of the whole working period are studied. And the cracking load and deformation regularity in various stages are obtained. The development process of cracks until the specimen damaged is revealed. At last, the development process of crack distribution at different stages is studied.

Abstract: A finite element model simulating the experiment on multiplanar unstiffened CHS KT joints with K-plane overlapped and out-of-plane not (KT-IPOv joints), with the background of Suzhou International Convention & Exhibition Center, was advanced and validated by comparing failure mode and the ultimate capacity with experimental results, which is shown to be in good agreement with the test result. Using this model, the effect of non-dimensional parameters on ultimate capacity of KT-IPOv joints were studied, and resistance comparison between multiplanar KT-IPOv joints and uniplanar overlapped K-joints was carried out. The results of FE parametric Analysis conclude that multiplanar parameter ζ _t, τT and βT have not significant influence on the ultimate strength; the effect of non-dimensional parameter β_K, τK, γ, Ov on the resistance of multiplanar KT-IPOv joints has the same as that of uniplanar overlapped K-joints; the strength of multiplanar KT-IPOv joints have been not significantly influenced by the configuration with the brace inside T-plane which it is not subjected to force; it is suitable and feasiable that ultimate capacities of KT-IPOv joints predicted by formula of uniplanar K-joints.

Abstract: The mechanical behaviors of intersecting joints considering damage accumulation in steel tube structures is analyzed through the FE-program ABAQUS. The stress characteristic and failure modes of these joints are concluded. Especially, it has been analyzed influence of the change of geometric parameters to mechanical behavior of joints. Finally, the results indicate the joints have a good mechanical performance and good plastic deformation as to excessive local buckling of chord under the loads.

Abstract: Abstract.The fire smoke is one of the most important factors for the fire temperature field. Once the fire smoke has been exhausted effectively, the fire temperature will be reduced and the fire-resistance performance of steel structures may be improved as well. However, the research on the fire temperature in the space structures is almost bold, which could lead to the theoretical analysis result on fire temperature is quite different from the real condition. Accordingly, the air temperature condition on fire for large-space structures has been analyzed. Taken into account smoke ventilation, the empirical formula for air temperature in large space structure under fire has been modified.