The mechanism of stress generation and propagation by detonation loading in five separate independent advance of ore breaking patterns is discussed in the paper. An elastic numerical model was developed using AN- SYS/...The mechanism of stress generation and propagation by detonation loading in five separate independent advance of ore breaking patterns is discussed in the paper. An elastic numerical model was developed using AN- SYS/LS-DYNA 3D Nonlinear Dynamic Finite Element Software. In this package ANSYS is the preprocessor and LS-DYNA is the postprocessor. Numerical models in the paper to actual were l:10 and the element mesh was dissected in scanning mode utilizing the symmetry characteristics of the numerical model. Five different advance rates were studied. Parameters, such as the time required to maximum stress, the action time of the available stress, the maximum velocity of the nodes, the stress penetration time, the magnitude of the stress peak and the time duration for high stress were numerically simulated. The 2.2 m advance appeared optimum from an analysis of the simulation results. The results from numerical simulation have been validated by tests with physical models.展开更多
The head-on collision process between ship and concrete pile supported protective system is simulated by software LS-DYNA. The influences of pile non-linearity and soil non-linearity on impact force, ship crush depth ...The head-on collision process between ship and concrete pile supported protective system is simulated by software LS-DYNA. The influences of pile non-linearity and soil non-linearity on impact force, ship crush depth and the cap displacement of pile supported protective system are discussed. It's shown that for both severe impact case and non-severe impact case, the non-linearity of pile material influence the impact force history, ship crush depth. The non-linearity of pile material and soil has remarkable influence on the cap displacement especially for severe impact case. These issues should not be ignored in the analysis of pile supported protective system subjected to ship impact.展开更多
According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-tru...According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-truss and bolting supporting. By the way of element simulation. The paper shows that single truss supporting have better effect to bolting supporting to improving the stress condition of surrounding rocks, controlling the surrounding rocks plastic failure development zone and deformation effect of surrounding rocks, which provided the elementary theory basis to the research, experiment and expanding the single-truss bolting technology in colliery.展开更多
The influence of cable sliding on the deployment of foldable cable-strut structures was studied in this paper. In order to develop an effective program for the cable sliding program, two-node cable element based on th...The influence of cable sliding on the deployment of foldable cable-strut structures was studied in this paper. In order to develop an effective program for the cable sliding program, two-node cable element based on the analytical solution of elastic cate- nary was studied. Then the cable sliding stiffness was defined as the ratio of the variation of the cable force to the variation of the cable length. To validate the proposed numerical method, analyses of two examples given in references were carried out. The results show that the method given in this paper is accurate and effective, which can be used to model the cable sliding in cable structures. Finally, the deployment process of a foldable cable-strut structure, which is composed of four-bar linkages and cables, was discussed. It can be found that the effect of cable sliding on the behavior of cable-strut structures is significant. The length changes of active cables are smaller when the cable sliding is considered. Moreover, the nodal coordinate changes also become faster when the numerical model is with cable sliding.展开更多
文摘The mechanism of stress generation and propagation by detonation loading in five separate independent advance of ore breaking patterns is discussed in the paper. An elastic numerical model was developed using AN- SYS/LS-DYNA 3D Nonlinear Dynamic Finite Element Software. In this package ANSYS is the preprocessor and LS-DYNA is the postprocessor. Numerical models in the paper to actual were l:10 and the element mesh was dissected in scanning mode utilizing the symmetry characteristics of the numerical model. Five different advance rates were studied. Parameters, such as the time required to maximum stress, the action time of the available stress, the maximum velocity of the nodes, the stress penetration time, the magnitude of the stress peak and the time duration for high stress were numerically simulated. The 2.2 m advance appeared optimum from an analysis of the simulation results. The results from numerical simulation have been validated by tests with physical models.
文摘The head-on collision process between ship and concrete pile supported protective system is simulated by software LS-DYNA. The influences of pile non-linearity and soil non-linearity on impact force, ship crush depth and the cap displacement of pile supported protective system are discussed. It's shown that for both severe impact case and non-severe impact case, the non-linearity of pile material influence the impact force history, ship crush depth. The non-linearity of pile material and soil has remarkable influence on the cap displacement especially for severe impact case. These issues should not be ignored in the analysis of pile supported protective system subjected to ship impact.
文摘According to the research results in world, the paper comprehensively analyzed and gave a demonstration of mechanism of single-truss and its stressing advantage. Comparison and analysis effect were given to single-truss and bolting supporting. By the way of element simulation. The paper shows that single truss supporting have better effect to bolting supporting to improving the stress condition of surrounding rocks, controlling the surrounding rocks plastic failure development zone and deformation effect of surrounding rocks, which provided the elementary theory basis to the research, experiment and expanding the single-truss bolting technology in colliery.
基金supported by the National Natural Science Foundation of China (Grant Nos. 50908044, 51278116)Jiangsu "Six Top Talents" Program (Grant No. 07-F-008)+1 种基金Scientific Research Foundation of Graduate School of Southeast University (Grant No. YBJJ0817)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The influence of cable sliding on the deployment of foldable cable-strut structures was studied in this paper. In order to develop an effective program for the cable sliding program, two-node cable element based on the analytical solution of elastic cate- nary was studied. Then the cable sliding stiffness was defined as the ratio of the variation of the cable force to the variation of the cable length. To validate the proposed numerical method, analyses of two examples given in references were carried out. The results show that the method given in this paper is accurate and effective, which can be used to model the cable sliding in cable structures. Finally, the deployment process of a foldable cable-strut structure, which is composed of four-bar linkages and cables, was discussed. It can be found that the effect of cable sliding on the behavior of cable-strut structures is significant. The length changes of active cables are smaller when the cable sliding is considered. Moreover, the nodal coordinate changes also become faster when the numerical model is with cable sliding.