In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with t...In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with through hole and reinforced structure subjected to hydrostatic pressure were carried out by the designed experimental test system.The mechanical responses of the composite shells under hydrostatic pressure are obtained by the high-speed camera and strain measurement.The results show that the entire deformation process of the shell can be divided into three:uniform compression,"buckling mode formation"and buckling.The"buckling mode formation"process is captured and reported for the first time.For the composite shell with single hole,the proposed reinforcing structure has a significant reinforcement effect on the shell and the buckling capacity of the shell is not weaker than the complete composite shell.For the composite shell with through hole,sealing effect can be achieved by the proposed reinforcing structure,but the buckling capacity of the shell after reinforcement can only reach 77%of the original buckling capacity.展开更多
The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic pressure.In this study,ovality and thickness variations as two repres...The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic pressure.In this study,ovality and thickness variations as two representative types of the geometric imperfections are considered.After measuring the geometric imperfections,a typical carbon fiber reinforced polymers(CFRP)cylindrical shell is tested to obtain the buckling pressure.The buckling behaviors of the shell sample are analyzed in combination with the strain responses.By using the nonlinear numerical analysis,the buckling shapes of the CFRP cylinder shells with different combinations of ovality and thickness variation are firstly discussed.The rules of influence of such imperfections on the buckling pressure are then obtained by nonlinear regression method.Finally,an empirical formula is proposed to predict the buckling pressure of the composite cylinder shells,and the calculated results from the formula are in good agreement with the numerical results.展开更多
基金supported by the Ningbo Major Research and Development Plan Project(Grant No.2024Z135)the Natural Science Basic Research Program of Shaanxi Province(Grant No.2024JC-YBMS-322)+1 种基金China Postdoctoral Science Foundation(Grant No.2020M673492)National Natural Science Foundation of China(Grant No.51909219)。
文摘In this paper,a type of reinforcing structure for composite shell with single and through hole is presented.The experimental tests for the composite shells without hole,with single hole and reinforced structure,with through hole and reinforced structure subjected to hydrostatic pressure were carried out by the designed experimental test system.The mechanical responses of the composite shells under hydrostatic pressure are obtained by the high-speed camera and strain measurement.The results show that the entire deformation process of the shell can be divided into three:uniform compression,"buckling mode formation"and buckling.The"buckling mode formation"process is captured and reported for the first time.For the composite shell with single hole,the proposed reinforcing structure has a significant reinforcement effect on the shell and the buckling capacity of the shell is not weaker than the complete composite shell.For the composite shell with through hole,sealing effect can be achieved by the proposed reinforcing structure,but the buckling capacity of the shell after reinforcement can only reach 77%of the original buckling capacity.
基金supported by the National Natural Science Foundation of China(Grant No.51909219)the National Key Research and Development Program of China(Grant No.2016YFC0301300)+1 种基金Fundamental Research Funds for the Central Universities(Grant No.3102019JC006)China Postdoctoral Science Foundation(Grand No.2020M673492)。
文摘The initial geometric imperfection is one of the primary factors affecting the buckling behaviors of composite cylindrical shells under hydrostatic pressure.In this study,ovality and thickness variations as two representative types of the geometric imperfections are considered.After measuring the geometric imperfections,a typical carbon fiber reinforced polymers(CFRP)cylindrical shell is tested to obtain the buckling pressure.The buckling behaviors of the shell sample are analyzed in combination with the strain responses.By using the nonlinear numerical analysis,the buckling shapes of the CFRP cylinder shells with different combinations of ovality and thickness variation are firstly discussed.The rules of influence of such imperfections on the buckling pressure are then obtained by nonlinear regression method.Finally,an empirical formula is proposed to predict the buckling pressure of the composite cylinder shells,and the calculated results from the formula are in good agreement with the numerical results.
