In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method（BEM）. The existing fullplane elastos...In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method（BEM）. The existing fullplane elastostatic fundamental solutions to displacement and stress fields were used and implemented in a developed algorithm. The cross-section of the tunnel was considered in circular, square, and horseshoe shapes and the lateral coefficient of the domain was assumed as unit quantity. Double-node procedure of the BEM was applied at the corners to improve the model including sudden traction changes. The results showed that the method used was a powerful tool for modeling underground openings under various external as well as internal loads. Eccentric loads significantly influenced the stress pattern of the surrounding tunnel. The achievements can be practically used in completing and modifying regulations for stability investigation of shallow tunnels.展开更多
Although several studies have examined the economic consequences of large shareholders＇ tunneling behavior, little attention has been paid to the negative effects of tunneling on firms＇ extreme events. In this artic...Although several studies have examined the economic consequences of large shareholders＇ tunneling behavior, little attention has been paid to the negative effects of tunneling on firms＇ extreme events. In this article, we investigate how tunneling behavior affects firm-level stock price crashes. The findings indicate that the probability of stock price crashes is positively associated with the extent of tunneling behavior by large shareholders. The positive relationship is more pronounced after the split of share structure reform and is moderated by the firm＇s financial conditions. This study contributes to the emerging body of literature focusing on the economic consequences of tunneling and stock price crashes. The conclusions drawn from the study also provide a frame of reference for investor protection and investment portfolios based on large shareholders＇ tunneling behavior in China.展开更多
文摘In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method（BEM）. The existing fullplane elastostatic fundamental solutions to displacement and stress fields were used and implemented in a developed algorithm. The cross-section of the tunnel was considered in circular, square, and horseshoe shapes and the lateral coefficient of the domain was assumed as unit quantity. Double-node procedure of the BEM was applied at the corners to improve the model including sudden traction changes. The results showed that the method used was a powerful tool for modeling underground openings under various external as well as internal loads. Eccentric loads significantly influenced the stress pattern of the surrounding tunnel. The achievements can be practically used in completing and modifying regulations for stability investigation of shallow tunnels.
基金We thank two anonymous referees and the editor who greatly improved the paper. Helpful comments were obtained from Xiangqin Qi, Fu Xin, Wei Xu, and Zhenye Yao from the seminars at Nanjing University. We acknowledge financial support from National Natural Science Foundation of China （Grant No. 71372032, 71302036 and 71272238） and the National Social Science Foundation （Grant No. 11AJL003）. Errors remain our own.
文摘Although several studies have examined the economic consequences of large shareholders＇ tunneling behavior, little attention has been paid to the negative effects of tunneling on firms＇ extreme events. In this article, we investigate how tunneling behavior affects firm-level stock price crashes. The findings indicate that the probability of stock price crashes is positively associated with the extent of tunneling behavior by large shareholders. The positive relationship is more pronounced after the split of share structure reform and is moderated by the firm＇s financial conditions. This study contributes to the emerging body of literature focusing on the economic consequences of tunneling and stock price crashes. The conclusions drawn from the study also provide a frame of reference for investor protection and investment portfolios based on large shareholders＇ tunneling behavior in China.
