This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the di...This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the disturbance range induced by tunneling and the minimum safe distance between the tunnel vault and the sliding belt are obtained in consideration of the mechanical analyses of relaxed rocks over the tunnel opening. The influence factors for the minimum safe crossing distance are conducted,including the tunnel radius, the friction angle of surrounding rocks, the inclination angle of sliding belt,and the friction coefficient of surrounding rocks. Secondly, taking account of the compressive zone and relaxed rocks caused by tunneling, the Sarma method is employed to calculate the safety factor of landslide. Finally, the analytical solutions for interaction between the tunnel and the landslide are compared with a series of numerical simulations, considering the cases for different perpendicular distances between the tunnel vault and the sliding belt. Resultsshow that the distance between the tunnel vault and the slip zone has significant influence on the rock stress and strain. For the case of the minimum crossing distance, a plastic zone in the landslide traversed by tunneling would be formed with rather large range, which seriously threatens the stability of landslide. This work demonstrates that the minimum safe crossing distance obtained from numerical simulation is in a good agreement with that calculated by the proposed analytical solutions.展开更多
To improve the convergence and distributivity of multi-objective particle swarm optimization,we propose a method for multi-objective particle swarm optimization by fusing multiple strategies(MOPSO-MS),which includes t...To improve the convergence and distributivity of multi-objective particle swarm optimization,we propose a method for multi-objective particle swarm optimization by fusing multiple strategies(MOPSO-MS),which includes three strategies.Firstly,the average crowding distance method is proposed,which takes into account the influence of individuals on the crowding distance and reduces the algorithm’s time complexity and computational cost,ensuring efficient external archive maintenance and improving the algorithm’s distribution.Secondly,the algorithm utilizes particle difference to guide adaptive inertia weights.In this way,the degree of disparity between a particle’s historical optimum and the population’s global optimum is used to determine the value of w.With different degrees of disparity,the size of w is adjusted nonlinearly,improving the algorithm’s convergence.Finally,the algorithm is designed to control the search direction by hierarchically selecting the globally optimal policy,which can avoid a single search direction and eliminate the lack of a random search direction,making the selection of the global optimal position more objective and comprehensive,and further improving the convergence of the algorithm.The MOPSO-MS is tested against seven other algorithms on the ZDT and DTLZ test functions,and the results show that the MOPSO-MS has significant advantages in terms of convergence and distributivity.展开更多
Hausdorff distance between two compact sets, defined as the maximum distance from a point of one set to another set, has many application in computer science. It is a good measure for the similarity of two sets. This ...Hausdorff distance between two compact sets, defined as the maximum distance from a point of one set to another set, has many application in computer science. It is a good measure for the similarity of two sets. This paper proves that the shape distance between two compact sets in R^n defined by nfinimum Hausdorff distance under rigid motions is a distance. The authors introduce similarity comparison problems in protein science, and propose that this measure may have good application to comparison of protein structure as well. For calculation of this distance, the authors give one dimensional formulas for problems （2, n）, （3, 3）, and （3, 4）. These formulas can reduce time needed for solving these problems. The authors did some data, this formula can reduce time needed to one As n increases, it would save more time. numerical experiments for （2, n）. On these sets of fifteenth of the best algorithms known on average.展开更多
基金financial support provided by Natural Science Foundation of China (Grant No. 51008188)by Shanghai Natural Science Foundation (Grant No. 15ZR1429400)+2 种基金by Open Project Program of State Key Laboratory Breeding Base of Mountain Bridge and Tunnel Engineering (Grant No. CQSLBF-Y15-1)by Open Project Program of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Grant No. SKLGP2015K015)by the Open Project Program of Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Land and Resources (Grant No. 2015k005)
文摘This paper focuses on the analytical derivation and the numerical simulation analyses to predict the interaction influences between a landslide and a new tunnel in mountain areas. Based on the slip-line theory, the disturbance range induced by tunneling and the minimum safe distance between the tunnel vault and the sliding belt are obtained in consideration of the mechanical analyses of relaxed rocks over the tunnel opening. The influence factors for the minimum safe crossing distance are conducted,including the tunnel radius, the friction angle of surrounding rocks, the inclination angle of sliding belt,and the friction coefficient of surrounding rocks. Secondly, taking account of the compressive zone and relaxed rocks caused by tunneling, the Sarma method is employed to calculate the safety factor of landslide. Finally, the analytical solutions for interaction between the tunnel and the landslide are compared with a series of numerical simulations, considering the cases for different perpendicular distances between the tunnel vault and the sliding belt. Resultsshow that the distance between the tunnel vault and the slip zone has significant influence on the rock stress and strain. For the case of the minimum crossing distance, a plastic zone in the landslide traversed by tunneling would be formed with rather large range, which seriously threatens the stability of landslide. This work demonstrates that the minimum safe crossing distance obtained from numerical simulation is in a good agreement with that calculated by the proposed analytical solutions.
基金National Natural Science Foundation of China(No.61702006)Open Fund of Key laboratory of Anhui Higher Education Institutes(No.CS2021-ZD01)。
文摘To improve the convergence and distributivity of multi-objective particle swarm optimization,we propose a method for multi-objective particle swarm optimization by fusing multiple strategies(MOPSO-MS),which includes three strategies.Firstly,the average crowding distance method is proposed,which takes into account the influence of individuals on the crowding distance and reduces the algorithm’s time complexity and computational cost,ensuring efficient external archive maintenance and improving the algorithm’s distribution.Secondly,the algorithm utilizes particle difference to guide adaptive inertia weights.In this way,the degree of disparity between a particle’s historical optimum and the population’s global optimum is used to determine the value of w.With different degrees of disparity,the size of w is adjusted nonlinearly,improving the algorithm’s convergence.Finally,the algorithm is designed to control the search direction by hierarchically selecting the globally optimal policy,which can avoid a single search direction and eliminate the lack of a random search direction,making the selection of the global optimal position more objective and comprehensive,and further improving the convergence of the algorithm.The MOPSO-MS is tested against seven other algorithms on the ZDT and DTLZ test functions,and the results show that the MOPSO-MS has significant advantages in terms of convergence and distributivity.
基金supported by the National Natural Science Foundation of China under Grant No. 10771206973 Project (2004CB318000) of China
文摘Hausdorff distance between two compact sets, defined as the maximum distance from a point of one set to another set, has many application in computer science. It is a good measure for the similarity of two sets. This paper proves that the shape distance between two compact sets in R^n defined by nfinimum Hausdorff distance under rigid motions is a distance. The authors introduce similarity comparison problems in protein science, and propose that this measure may have good application to comparison of protein structure as well. For calculation of this distance, the authors give one dimensional formulas for problems （2, n）, （3, 3）, and （3, 4）. These formulas can reduce time needed for solving these problems. The authors did some data, this formula can reduce time needed to one As n increases, it would save more time. numerical experiments for （2, n）. On these sets of fifteenth of the best algorithms known on average.
