Papers by Keyword: Biaxial Load

Abstract: The paper focuses on the research of mechanical behavior of the CFRP steel reinforced concrete filled with steel tube column under biaxial load. The authors make a simulated analysis mode with the general finite element analyze software, ABAQUS. By the way of unit selecting, meshing, contact setting, the mode is calculated by the ABAQUS/Standard which is used to analyze the mechanical behavior of the specimens. Based on comparing the load-displacement curves under different axial compression ratios, it can conclude that with the increasing of compression, the ultimate load reduces obviously. At the same time, the ductility coefficient also descended slowly. All the ductility coefficients of different specimens are all larger than 2, which meet the code very well. So the mechanical behavior of the column is very well.

Abstract: In this study, elastic-plastic stress and strain fields were analyzed on hole-edge cracks in an aluminum alloy plate under the biaxial load. And the effects of the load parallel to the crack face on failure parameters were discussed. By quantifying the effects of the crack size and the loading mode on the crack propagation driving force, J integral, and the plastic limit load, the corresponding failure assessment curves of the hole-edge cracked plate were established with the new R6 failure assessment diagram (FAD) method. The result shows that the transverse load has a larger effect on the failure assessment curve than crack length does, the safety zone of the failure assessment diagram gradually becomes smaller while transverse loading stress changes from tensile condition to compressed. Especially, when the transverse load acts as pressure, the Option 3 failure assessment diagram results to a smaller safety zone than the Option 1 failure assessment diagram does.

Abstract: Based on the J-A₂ two-parameter elastic-plastic fracture theory and finite element numerical method, the elastic-plastic stress field ahead of the crack tip in a single edge cracked eccentric tensile specimen (the load-line is at a finite distance from the crack tip) was analyzed and compared with that of a center cracked large plate under biaxial loading. By using the Ritchie-Knott-Rice fracture criterion, a transformational relation between the two loading modes was obtained based on the J-A₂ equivalent principle. As a result, the fracture parameter determined from a single edge cracked eccentric tensile specimen can be applied to the fracture analysis of a center cracked plate under biaxial stress.

Abstract: Ductile honeycombs under in-plane biaxial loads fail by elastic buckling, plastic yielding and fast fracture of solid cell edges, while brittle honeycombs fail by elastic buckling, brittle rupturing and fast fracture of solid cell edges. In the paper, we aim at summarizing the modeling and theoretical expressions for describing the failure surfaces of honeycombs with non-uniform thickness cell edges under in-plane biaxial loads. Hence, the failure surfaces of ductile honeycombs with plateau borders are generated and found to be dependent on the solid distribution in cell edges and the yielding strengths of solid cell edges. Also, the failure surfaces of brittle honeycombs with plateau borders are significantly affected by the cell-edge modulus of rupture and the solid distribution in cell edges.

Abstract: Based on detailed two-dimensional (2-D) and three-dimensional (3-D) finite element (FE)analyses, this paper attempts to quantify in-plane and out-of-plane constraint effects on elastic-plastic J and cracked tip stresses for biaxially loaded plate with a through-thickness crack and semi-elliptical surface crack. It is found that the reference stress based approach for uniaxial loading can be applied to estimate J under biaxial loading, provided that the limit load specific to biaxial loading is used, implying that quantification of the biaxiality effect on the limit load is important. Investigation on the effect of biaxiality on the limit load suggests that for relatively thin plates with small cracks, in particular with semi-elliptical surface cracks, the effect of biaxiality on the limit load can be neglected, and thus elastic-plastic J for a biaxially loaded plate could be estimated, assuming that such plate is subject to uniaxial load. Regarding the effect of biaxiality on crack tip stress triaxiality, it is found that such effect is more pronounced for a thicker plate. For plates with semi-elliptical surface cracks, the crack aspect ratio is found to be more important than the relative crack depth, and the effect of biaxiality on crack tip stress triaxiality is found to be more pronounced near the surface points along the crack front.