Advanced Materials Research Vols. 671-674

Abstract: 4 steel bar reinforced high-strength concrete column specimens were tested under axial compression in order to study how different height width ratios, different stirrup ratios and different steel bar reinforcement ratios influence the failure mode of the members and the bearing capacity. Results show that the steel bar reinforced high-strength concrete columns are applicable to practical engineering.

Abstract: This paper presents an experimental investigation and a numerical analysis on the bending strength and behavior of cold-formed steel C-section and ∑-section beams with complex edge stiffeners and web holes. Local buckling, distortional buckling and interaction between local and distortional buckling were observed in the tests. The experimental results show that the stiffened web has great influence on member's bending strength. Compared with C-section specimens, the stiffness of the web stiffeners of ∑-section specimens reduced the influence of the holes. The finite element analysis results show good agreement with the experimental results in terms of bending strength and buckling mode.

Abstract: As a new material type, elastic concrete has been used in pavement and bridge deck paving due to its superior properties to ordinary concrete. Nowadays, fatigue behavior of steel-concrete composite beams has become the focus in engineering design. This paper summarized the research status, methods, influence factors on fatigue behavior of elastic concrete and steel-concrete composite beams and compared various fatigue specifications among different countries. The result shows that elastic concrete has longer fatigue life than ordinary concrete, so we can solve fatigue problems by using elastic concrete instead of ordinary concrete in composite beams. Finally the author puts forward suggestions for further advanced study in this area.

Abstract: Shear strength and stiffness of fire-damaged reinforced concrete (RC) beams were researched. The nonlinear finite element method (FEM) was developed to simulate shear strength of fire-damaged RC beams. Considering mechanical properties deterioration of concrete and steel reinforcing bar, the parameters of fire-damaged RC beams, including fire exposure time, shear span to depth ratios, concrete strength, diameters of stirrups and spacing of stirrups, were analyzed. Based on numerical analysis, the change of shear strength and stiffness of fire-damaged RC beams were identified. The results showed that shear strength and stiffness of fire-damaged RC beams changed under different parameters. With increase of fire exposure time or increase of shear span to depth ratio or decrease of concrete strength, shear strength and stiffness of fire-damaged RC beams descended obviously. With decrease of diameters of stirrups or increase of spacing of stirrups, shear strength of fire-damaged RC beams descended gradually, but stiffness of fire-damaged RC beams had little change.

Abstract: The fire protection method of steel space truss structures was researched. Fire protection methods of steel structures were listed. For steel space truss structures, the advantages and disadvantages of fire protection methods were introduced. The screen method was suitable for fire protection of steel space truss structures. One project of fire protection of steel space truss structure was shown as an example. The process of screen method was provided for fire protection of steel space truss structures. According to this project, the technology of fire protection of steel space truss structures was enriched. The research results could help to deal with fire protection of steel space truss structures.

Abstract: This paper presents experimental research on axial structural behaviour of 14 short wood columns externally strengthened with CFRP, BFRP and AFRP fibers. All columns for tests were subjected to axial compressive load. The work carried out has indicated how different types of fiber cloth, strengthened arrangements and fiber layers affect behaviour of the short reinforced wooden columns. Research output shows that carrying capacity, stiffness and ductility of FRP reinforced wood columns is improved, and the increasing relationship between the reinforcement layers and bearing capacity is not linear. The all-bonded reinforcement scheme is better than semi-bonded one, and the semi-bonded one is better than the interval-bonded one. The performance of CFRP and BFRP reinforced columns is applied fully. This study confirms that the FRP reinforcing technique significantly enhances the carrying capacity of short wood columns.

Abstract: In the modern construction process, the wall cracks in residential buildings in the more general question, which the concrete cracks. Concrete cracks caused by a variety of reasons, such as temperature changes, uneven ground subsidence, wall expansion and contraction, there are some cracks by external effects or conservation measures is wrong or some chemical reaction causing the problem. In this paper, architectural design, building materials, construction and other aspects to analyze and propose some solutions approach.

Abstract: The numerical analysis method is applied to simulate the whole process of bending. Keeping the section dimensions and the types of loads constant in prestressed concrete hollow slab with mid-strength spiral-rib steel wire, strength of concrete, strength of steel bar, reinforcement ratio, span-depth ratio and stretching control stress are analyzed and compared. The influence of span-depth ratio to the ductile property in prestressed concrete hollow slab is discussed by numerical simulation.

Abstract: China is a developing country, and also a quake-prone country. On the one hand is the Special national conditions that per capita energy shortage and frequent earthquakes, on the other hand is the social economy development and people's living environment requirements continue to increase, both of them raised new requirement of China’s residence system development. Light steel structure residence is energy conservation , environmental protection, safety and seismic, these unique advantages just to meet the current development of residential industry in China, so it has a good development prospect. This article start from the realistic background, around the application and development of our country’s light steel structure residence presently, mainly introduced the characteristics of light steel structure residence, the impact of construction industry, and the social benefits, environmental benefits, housing industrialization effective and comprehensive benefits it can produce.

Abstract: The supporting conditions have important effects on deformation of grid structure. This paper takes a long-span space truss structure as the research object, and a modal analysis of the grid structure under different supporting conditions is carried out by the finite element software. It is found that the grid structure of trilateral supporting and both sides supporting has big deformation due to the existence of free edges, which is adverse to the deflection of grid structure. Therefore, free edges should be treated properly in practical engineering, in order to improve the stress states of grid structure. With the increase of order, the natural frequencies of grid structure under different supporting conditions grow incrementally through modal analysis. In the same order, the natural frequency of two sides supporting is minimum, while the peripheral supporting is maximum.