Moraine-dammed lake outbursts usually threaten highways, railways, and key facilities in alpine regions. The varying amplitudes and distribution of hydrodynamic pressures significantly affect the stability of the dam....Moraine-dammed lake outbursts usually threaten highways, railways, and key facilities in alpine regions. The varying amplitudes and distribution of hydrodynamic pressures significantly affect the stability of the dam. We utilize a shaking table to investigate the development of hydrodynamic pressure caused by different sinusoidal waves and seismic Wolong wave. A series of shaking table tests indicate that the hydrodynamic pressure varia- tion significantly follows seismic acceleration wave motion. The maximum hydrodynamic pressures calculated by Westergaard＇s equation are compared with the experi- mental values under different waves. It is shown that the Westergaard＇s values are lower than the experimental ones under the sinusoidal waves. However, the Westergaard＇s method is able to predict the earthquake-induced hydro- dynamic pressure caused by Wolong wave in small lake with desirable accuracy.展开更多
The relatively high stress probably leads to generation of a fractured or even instable area around a working coalface. Also, the generated weak area often evolves into an easy-infiltrating field of water/gas to great...The relatively high stress probably leads to generation of a fractured or even instable area around a working coalface. Also, the generated weak area often evolves into an easy-infiltrating field of water/gas to greatly increase probability of accident occurrence. To reveal the distribution of high stress around working faces, we put forward the mode-I-crack compression model. In this model, the goaf following a working face is regarded as a mode-I crack in an infinite plate, and the self-gravity of overlaying strata is transformed into an uniform pressure applied normal to the upper edge of the model crack. Solving this problem is based on the Westergaard complex stress function. For comparison, the software RFPA-2D is also employed to simulate the same mining problem, and furthermore extendedly to calculate the stress interference induced by the simultaneous advances of two different working faces. The results show that, the area close to a working face or the goaf tail has the maximum stress, and the stress is distributed directly proportional to the square root of the advance and inversely proportional to the square root of the distance to the working face. The simultaneous advances of two neighboring working faces in different horizontals can lead to extremely high resultant stress in an interference area.展开更多
基金financially supported by the Natural Science Foundation of China under contract No.41571004National Key Research and Development Program(Grant No.2016YFC0802206)Research and Development Program of Science and Technology of China Railway Corporation(Grant No.2015G002-N)
文摘Moraine-dammed lake outbursts usually threaten highways, railways, and key facilities in alpine regions. The varying amplitudes and distribution of hydrodynamic pressures significantly affect the stability of the dam. We utilize a shaking table to investigate the development of hydrodynamic pressure caused by different sinusoidal waves and seismic Wolong wave. A series of shaking table tests indicate that the hydrodynamic pressure varia- tion significantly follows seismic acceleration wave motion. The maximum hydrodynamic pressures calculated by Westergaard＇s equation are compared with the experi- mental values under different waves. It is shown that the Westergaard＇s values are lower than the experimental ones under the sinusoidal waves. However, the Westergaard＇s method is able to predict the earthquake-induced hydro- dynamic pressure caused by Wolong wave in small lake with desirable accuracy.
基金Projects 50774083 and 40811120546 supported by the National Natural Science Foundation of ChinaNCET-07-0803 by the Program for New Century Ex-cellent Talents in University 2005CB221502 by the National Basic Research Program of China
文摘The relatively high stress probably leads to generation of a fractured or even instable area around a working coalface. Also, the generated weak area often evolves into an easy-infiltrating field of water/gas to greatly increase probability of accident occurrence. To reveal the distribution of high stress around working faces, we put forward the mode-I-crack compression model. In this model, the goaf following a working face is regarded as a mode-I crack in an infinite plate, and the self-gravity of overlaying strata is transformed into an uniform pressure applied normal to the upper edge of the model crack. Solving this problem is based on the Westergaard complex stress function. For comparison, the software RFPA-2D is also employed to simulate the same mining problem, and furthermore extendedly to calculate the stress interference induced by the simultaneous advances of two different working faces. The results show that, the area close to a working face or the goaf tail has the maximum stress, and the stress is distributed directly proportional to the square root of the advance and inversely proportional to the square root of the distance to the working face. The simultaneous advances of two neighboring working faces in different horizontals can lead to extremely high resultant stress in an interference area.
