Based on the plastic deformation theory and energy method, the critical blank-holder forces (BHF) of wrinkling and fracture in the cylindrical cup deep-drawing are analyzed. The verify experiments were performed and c...Based on the plastic deformation theory and energy method, the critical blank-holder forces (BHF) of wrinkling and fracture in the cylindrical cup deep-drawing are analyzed. The verify experiments were performed and compared with the theory analysis results. The predictions agree well with the experiment results. Thus, the validated presenttheoretical analysis model may be applied to determinate the suitable BHF.展开更多
In this paper, the effect of variable Blank-holder forces (VBHF) on the strain path during sheet metal forming has been investigated by numerical simulation and experiments. The formability of select aluminum alloy sh...In this paper, the effect of variable Blank-holder forces (VBHF) on the strain path during sheet metal forming has been investigated by numerical simulation and experiments. The formability of select aluminum alloy sheet was evaluated by theory prediction of forming limit curve based on the M-K method. The effect of different VBHF on the formability was presented. In order to verify the predictions of strain path, experiments are being carried out using a recently-built multi-points variable blank-holder forces hydraulic press. The results show that large side BHF with small comer BHF during rectangular box deep drawing can improve the formability of the selected aluminum alloy展开更多
In order to establish a restoring-force model for modified concrete columns with recycled aggregates concrete(RAC), cyclic loading tests were carried out on five concretes with RAC columns and ordinary concrete frame ...In order to establish a restoring-force model for modified concrete columns with recycled aggregates concrete(RAC), cyclic loading tests were carried out on five concretes with RAC columns and ordinary concrete frame columns under the combined influence with different admixtures and admixtures ratios(silica fume and hybrid fiber). The expressions for characteristic nodes of the skeleton curve were given by the analysis and numerical regression of the test results. In addition, the hysteretic rules of the restoring-force model and the expression for unloading stiffness were presented. Finally, we summed up the complete calculation method of the hysteretic restoring force, whose results were in good agreement with experiment. The results demonstrated that the proposed model could simulate and reflect the corresponding hysteretic behaviors, and the calculation method can provide the theoretical basis for the engineering application.展开更多
基金This research was supported by the National Natural Science Foundation of China
文摘Based on the plastic deformation theory and energy method, the critical blank-holder forces (BHF) of wrinkling and fracture in the cylindrical cup deep-drawing are analyzed. The verify experiments were performed and compared with the theory analysis results. The predictions agree well with the experiment results. Thus, the validated presenttheoretical analysis model may be applied to determinate the suitable BHF.
基金This research was supported by the National Natural Science Foundation of China
文摘In this paper, the effect of variable Blank-holder forces (VBHF) on the strain path during sheet metal forming has been investigated by numerical simulation and experiments. The formability of select aluminum alloy sheet was evaluated by theory prediction of forming limit curve based on the M-K method. The effect of different VBHF on the formability was presented. In order to verify the predictions of strain path, experiments are being carried out using a recently-built multi-points variable blank-holder forces hydraulic press. The results show that large side BHF with small comer BHF during rectangular box deep drawing can improve the formability of the selected aluminum alloy
基金Project(51178388)supported by the National Natural Science Foundation of ChinaProject(2013SZS01-Z02)supported by Key Laboratory Fund of Shaanxi Province,China
文摘In order to establish a restoring-force model for modified concrete columns with recycled aggregates concrete(RAC), cyclic loading tests were carried out on five concretes with RAC columns and ordinary concrete frame columns under the combined influence with different admixtures and admixtures ratios(silica fume and hybrid fiber). The expressions for characteristic nodes of the skeleton curve were given by the analysis and numerical regression of the test results. In addition, the hysteretic rules of the restoring-force model and the expression for unloading stiffness were presented. Finally, we summed up the complete calculation method of the hysteretic restoring force, whose results were in good agreement with experiment. The results demonstrated that the proposed model could simulate and reflect the corresponding hysteretic behaviors, and the calculation method can provide the theoretical basis for the engineering application.
