Advanced Materials Research Vols. 368-373

Abstract: The influence on columns behaviors of slenderness ratio are analyzed, and the influence on columns’ anti-seismic behavior of axial compression ratio, stirrup ratio and steel form are analyzed through the test on bearing capacity and level load of low cycle reverse of steel reinforced high-strength concrete columns. The bearing capacity of the long columns reduces along with the slenderness ratio increasing and augments along with concrete strength increasing. Probability of suddenly destruct increases along with the column slenderness ratio augmenting through the test. In addition, anti-seismic behavior of columns are effected not only axial compression ratio, but also steel form. Axial compression coefficien of the steel reinforced high-strength concrete columns with different steel form may be adjusted, however, the influence of stirrup ratio is very little on anti-seismic behavior of columns.

Abstract: For the aluminum alloy pipe stable form and buckling capacity, axis compressing test for 4 sections which each specification in three members, total 36 members, thus, we work out the ultimate bearing capacity for a little slenderness ratio alloy round pipe and relation between slenderness ratio and coefficient of stability, to provide test data for drawing pillars curve of the same type member. Through observed aluminum alloy compressing member changing with test process, record test phenomenon, and combined with instruments of test data record, providing the basis for further theoretical analysis.

Abstract: This study, in order to identify the effects that the mixed-use of long and short fiber has on the mechanical characteristics of UHPC, we used a steel fiber of 65, 82 and 98 in a shape ratio (l/d) alternating from the length of 13, 16,3 and 19.5 mm respectively in the short fiber with a diameter of 0.2 mm and used the hooked-type high-elasticity steel fiber with a diameter of 0.375 and the length of 30 mm of the long fiber. As a result, it was found that, in constructability and compressive behavior in the same fiber mixing ratio, the more the mixed amount of short fiber, the higher the compressive strength, but it was analyzed that the increase of width was very narrow. According to the results from the review on the flexural tensile behavior of UHPC to make a hybrid from the straight-short and hooked-long fiber, it was analyzed that the use of hybrid fiber does not significantly contribute to the enhancement of the flexural strength of UHPC, however, it greatly contributes to the enhancement of the flexural toughness. In the case of using the fiber in this method, it was analyzed that it would be possible to manufacture UHPC which is superior in workability and mechanical characteristics and economically feasible.

Abstract: Steel reinforced concrete (SRC) cross beam has high stiffness and seismic resistance capability, but it is difficult to determine a reasonable beam span-height ratio in engineering applications because there is no general theory in this area. In this paper, we developed a numerical model for SRC cross beam deflection simulation, in which the effect of cast-in-situ concrete floor on the beam has been taken into consideration as an effective flange of the beam. We also investigated the effect of the beam cambering limits in construction on beam deflection under different span-height ratios. The numerical results shows that seismic action and wind load have little effect on the span-height ratio, while beam cambering in construction is very favorable to decrease beam deflection. In addition, steel stiffness has great influence on the deflection of cross beam, and elastic deflection is only one fourth of the actual deflection. Therefore, the reasonable span-height ratio of SRC cross beam should be 20 to 30.

Abstract: In the process of prefabricating some genenal box girder,T girder,I girder,cored slab,a tension of prestress will give rise to the camber which is the important evaluation criterion of bridge engineering quality[1].This paper take XiHuXiuZi bridge and FuXingPao bridge as background to research elastic camber of prefabricated PC girder.Then the model of prefabricated PC girder is established through finite element analysis software Ansys.The model data is compared with the collected data after finishing the model.The factor which can impact elastic camber is researched deeply.Lastly,the relations between the elastic camber of prefabricated PC girder and each influential factors is determined through changing model parameters.

Abstract: The stability of reticulated shell is a key issue for single-layer reticulated shell. In the paper, a single-layer arch-supported shell structure was analyzed by finite element software MIDAS. The eigenvalue buckling analysis and the geometric nonlinear overall stability analysis with initial imperfection of the model which carried two different load combinations were studied too. At the same time, the influences on the stability of the shell structure were researched. The results showed that the shell structure was sensitive to the initial imperfection. Under different load combinations, the instability of modes and limited capacity of stability are different in the shell structure.

Abstract: In this article, graft copolymerization of styrene (St) onto cassava starch via potassium diperiodatonickelate (IV)–starch redox system as an initiator was investigated in an alkaline medium. The effects of reaction variables were investigated, and the grafting conditions were optimized. The equation of the polymerization rate were obtained, Rp= k•C^1.02 (St)•C^0.53 (Ni（IV）). The graft copolymer was characterized with Fourier-transform infrared spectra analysis (FTIR) and scanning electron microscopy (SEM). FTIR spectra indicated the presence of PSt-g-starch copolymer. SEM micrographs also showed PSt adhering on the starch.

Abstract: For seismic design of composite frame and reinforced concrete core hybrid structures in high-rise buildings, the response spectrum method is influenced to a large extent by mode combination rules and number of combined modes. The dynamic characteristics of composite frame and concrete core hybrid structures were studied through modal analysis, natural vibration periods and mode shape of hybrid structures had calculated and analyzed, the results show that the natural vibration frequencies are near, the complete quadratic combination of mode combination rule was recommended for avoiding higher order mode shape lose in the response spectrum method. The reasonable number of combined modes for response spectrum method were studied by truncation error analysis, it is proposed that more than 20 modes are combined. The results of the time history analysis und The three dimensional finite element er three earthquake waves were compared with results of response spectrum, indicating that the maximum response of hybrid structures can be obtained under reasonable mode number.

Abstract: This epoxy asphalt used by the U.S., Japan Epoxy Asphalt two steel bridge deck pavement materials at different thickness analysis of pavement deformation force. Pavement derived the maximum tensile stress, shear stress and elastic modulus, pavement thickness of mathematical models. The results showed that: Pavement maximum tensile stress, shear stress, pavement elastic modulus with available four times a polynomial equation fitted, pavement surface transverse maximum stress increases as the pavement thickness decreases, horizontal maximum shear stress between layers does not increase with the pavement thickness decreases, but the thickness of the pavement at 40-50mm have a peak, then gradually increases with the thickness decreases.

Abstract: The finite element formulation was used to analyze the influences of structural parameters such as the skewed angle and the stiffness ratio of flexure to torsion on the distributions of moment and torsion. The moment and torsion factors figure were presented according to the different structural parameters such as the skewed angle and the stiffness ratio of flexure to torsion. Some equivalent load vectors of non-nodal load acting on the skewed supported beam were derived.