Advanced Materials Research Vols. 594-597

Abstract: At present, there are much more researches on the ordinary concrete composite slab, and that on the lightweight aggregate concrete composite slab are relatively less. In this paper, the shear-bond behavior of lightweight aggregate concrete composite slab, with the profiled steel sheet YX-76-344-688, which is commonly used in China is studied. Base on experiments, the cracks developing process and its regularities of distribution, the bonding and slipping between profiled sheeting and concrete, the relationship of load and mid-span deflection, ultimate bearing capacity etc. are studied.

Abstract: In this paper, the analysis on dynamic failure behaviors of steel double-layer landing spherical latticed shell used in a gymnasium with the function of earthquake victim shelter 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. The plastic development level of the rod, the deformed shape and the failure type and the ductility are estimated. The results show that the failure model of the structure under the earthquake wave action is the complicated combination of strength failure and elasto-plastic dynamic local buckling in deferent areas of the structure; When the structure reached its failure critical limit, the development of the plastic hinges is sufficient and 38.4% of the rods enter into their plastic stage; The ratio of its maximal failure node vertical displacement and its plane diameter is 1/139; Its critical failure peak acceleration of EL earthquake wave when applied in the combination of three directions is 2090gal, which is 5 times more than the official seismic fortification level of 8 degree (major earthquake, 0.2g) and can be served as earthquake victims shelter in the area of 8 degree seismic fortification; Its displacement ductility coefficient is 8.64,which shows the structure owns good energy dissipation capacity.

Abstract: The tube and coupled scaffold is widely used in the construction of building, bridge, sports stadium etc, due to the advantage of easily assembling, high load capacity and good overall stiffness. However as a very important temporary structure in the construction, the semi-empirical method has been used for the calculation of ultimate load capacity (ULC), whether the calculation results are acceptable is not given too much attention. To ascertain the safety of using process, the FEM code-Midas is used to investigate and compare the stability and ultimate load analysis method of scaffold, and the impacting factors, such as the span, step distance, height, and width of scaffold, are discussed, the varying process and trend is described in this paper.

Abstract: The paper presented the application of Excel software in the constructing and plotting of the influence lines in the statically determinate plane trusses. Obtaining the influencing coefficient of the statically determinate plane trusses with Excel, the influence lines were constructed and plotted. The research results of this paper have important reference and actual using value to engineering practice, teaching and research work.

Abstract: Main factors of the temperature control and crack prevention in arch dams are summarized. The Space-time Dynamic Control method in pipe cooling process and the Temperature Real-time Control and Decision Database System are introduced to help for temperature real-time control and rapid analysis. Successful application of these new techniques in the construction of Dagangshan arch dam indicates that the proposed method are of significant effectiveness on the temperature control and crack prevention, and have good application prospect in practical project.

Abstract: With the continuous improvement of China’s construction technology, the application of mass concrete structures is increasingly popular in various structures in order to meet the requirements of structure and function, such as tall buildings, dams, railways and highways. There are all kinds of cracks in construction process because of the big cross section. There are many reasons to form cracks, but temperature is the most common cause. It is vital to the construction quality of mass concrete that the hydration heat, especially the peak value of temperature rise, is calculated in advance and precautions are implement in construction process accordingly. In this article, the calculation formula modified is derived through analyzing the common calculation formulas of mass concrete, the actual measurement results and the influencing factors of temperature rise.

Abstract: Cold-formed U-shaped steel and concrete composite beam is a kind of composite beam which the steel and the concrete are integrated by welding connections on the cold-formed U-shaped steel and then pouring concrete on the steel. Now, many experts and scholars have carried out many experimental research and theoretical analysis about it. But, prestressed Cold-formed U-shaped steel and concrete composite beams have not been studied. Based on the structure , the nonlinear analysis mode of prestressed cold-formed U-shaped steel and concrete composite beams is proposed, the calculating program is researched. The calculating results show that the bearing capacity of composite beam increases with the increments of thickness of steel plate and concrete strength, and the thickness of steel plate has a larger effect than the width of the flange plate of concrete, applying prestress can enhance the bearing capacity and flexural rigidity of the composite beam.

Abstract: According to the respective characteristics of the tensioning structure and flat grid, analyzed the static characteristics of new style cable-pole composite grid structure, put forward the basic assumption of the calculation and theoretical analysis method, comparative analysis of the positive four pyramid and obliquely placed four pyramid cable-pole deflection and internal force of composite grid structure changes, discussed the economy and feasibility of cable - pole composite grid structure. This article has a certain reference value to the cable- pole combined network engineering design.

Abstract: The glass fiber reinforced polymer (GFRP) I-beams were tested under the third-point static loading. The load, mid-span deflection and failure modes were recorded during the flexural test. The flexural property was analyzed. The test results indicate that local buckling result in failure of integral structure. The local stability of flange plate is one of the main factors that affect the overall bending capacity of GFRP I-beams. Local strengthening should be adopted in the flange-web joint.

Abstract: The reliability control of reinforced concrete structure during construction is important for ensuring the safety of the structure. The paper puts forth the main influence factors of construction quality and the control measures of these factors through the discussion of reliability control of construction quality, and given the processing method of quality defects of reinforced concrete structure during construction.