Applied Mechanics and Materials Vols. 256-259

Abstract: The aim of this article is in description of behavior and bearing capacity of one-shear nail joints in joints of cement-splinter boards with middle solid wood element on the base of destructive laboratory testing according to valid European standards [1]. The second part of this paper describes typical damage of these joints and comparison of these results with bearing capacity of the same way arranged and loaded joints, where however instead of cement-splinter board solid wood boards were used.

Abstract: In order to improve the capacity of resistance to progressive collapse for steel frame structures, a new measure, which uses bracing systems to help damaged frame to bridge across the local damage caused by abnormal loads, is presented in this study. The dynamic progressive collapse analysis is carried out to investigate the effect of resistance to progressive collapse in two different cases of column removal. Analytical results show that bracing systems on the top of steel frame structure have obvious effects on collapse prevention. Comparison with the unbraced steel frame structure, fixing bracing system could decrease the vertical displacement of the node corresponding to the top of the removed columns, and reduce the moment peak value at the end section of beams. And after column removal, plastic hinges come into being in the unbraced steel frame, on the other hand, there are no plastic hinges formed in the steel frame with bracing system.

Abstract: The pre-stressed stainless steel wire mesh (SSWM) –mortar (M) is a pre-stressed laminate structure for structural strengthening and rehabilitation. Pre-stressing the stainless steel wire mesh is the key technology for engineering practice. A jogged anchor is proposed for anchoring large diameter SSWM conveniently. The flexural performances of 5 damaged RC beams strengthened by pre-stressed SSWM-M and one referential RC beam were tested. The experimental results indicates that the large diameter pre-stressed SSWM-M has a better performance in controlling the crack growth, restoring the flexural capacity and stiffness than the small diameter pre-stressed SSWM-M.

Abstract: The dynamics of elastic support beam are studied and the latent equation of the freely vibration modes of elastic bearing beam is deduced. The equation of the forced vibration of an elastically supported beam is obtained by the Lagrange equations and the influence of spring stiffness and moving load speed are analyzed. Calculation results show: the elastic supports have great effects on responses of beams, the dynamic amplification of deflections and stresses increases with the spring stiffness; the dynamic response of beam also increase with the increase of the speed of moving loads.

Abstract: The shape of heterotypic spatial plate and shell structure is irregular, the performance of force is complex, so it is necessary to analyze the stress performance for this heterotypic spatial plate and shell structure, and understand the stress characteristics. By using the finite element program MIDAS to analyze its mechanical properties in elastic stage, and put forward the deformation coefficient of K to embody the deformation performance of spatial plate and shell structure. Through analyzing the influence factors, such as inclination of shell, concrete strength and thickness of shell, to effect mechanical properties of the heterotypic spatial plate and shell structure.

Abstract: In order to study the shear capacity enhancement effect of prestressed technology to steel fiber reinforced concrete, the practical formulas were proposed for evaluating the shear-strength of unbonded prestressed steel-fiber reinforced concrete beams (UPSFRCB) through the test and study of shear capacity of UPSFRCB with simply supported ends. Various factors affecting the shear strength of UPSFRCB, such as steel fiber, prestress and shear-span to depth ratio were analyzed. The result is of importance to the popularization and application of prestressed steel-fiber reinforced concrete.

Abstract: The paper introduces the importance of stability and current reseach status on prestressed concrete cable-beam structure system.It demonstrates the basic relative theory on stability in concretely research and applies this theory into the prestressed concrete cable-beam structure system,the formula of stability on this system is come true to make the analyze prestressed concrete cable-beam structure system precisely.

Abstract: With the rapid development of building process of industrialization in China, obtained the rapid development of precast concrete frame structures. This article is reading about precast concrete frame structure system at home and abroad on the basis of article. For describes precast concrete frame structure project background and the testing of components, to research the behaviors of precast concrete frame structure system.

Abstract: In this paper, an attempt to overcome the problem of brittleness of concrete, by adding polypropylene fibers to the concrete is made. The performance of the polypropylene fiber reinforced concrete will be investigated experimentall under two point middle third of monotonic load for various types of polypropylene fibers and FRP Wrapping.

Abstract: A comparative study is conducted on the seismic behaviors of five 1/2 scale recycled concrete short columns with 1.75 shear span ratios. The stirrup ratio in the specimens was changed from 0.4%, 0.9%, to 1.29% while the ratio of their longitudinal reinforcement was the same. Crossed reinforcing bars were set in two of the specimens. Cyclic loading test was carried out for the specimens under axial compression ratio 0.4. The stiffness and its degradation, load-carrying capacity, ductility, hysteretic behavior, energy dissipation and failure phenomena of each short column were analyzed. Results show that, with the increase of the stirrup ratio in the specimens, the shear failure of the specimens is getting lighter and lighter. And the load-carrying capacity, ductility, energy dissipation capacity are improved greatly, but the rate of the increase is tending to slow. Moreover, crossed reinforcing bars in the short columns are able to improve the seismic behavior. Recycled concrete can be used for structural columns with low axial compression ratio in earthquake area.