<th id="5nh9l"></th><strike id="5nh9l"></strike><th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th><strike id="5nh9l"></strike>
<progress id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"><noframes id="5nh9l">
<th id="5nh9l"></th> <strike id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span>
<progress id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span><strike id="5nh9l"><noframes id="5nh9l"><strike id="5nh9l"></strike>
<span id="5nh9l"><noframes id="5nh9l">
<span id="5nh9l"><noframes id="5nh9l">
<span id="5nh9l"></span><span id="5nh9l"><video id="5nh9l"></video></span>
<th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th>
<progress id="5nh9l"><noframes id="5nh9l">

巖爆結構面強度的弱化特征

Strength weakening characteristic of rock burst structural planes

  • 摘要: 巖爆破壞以其突發性與瞬間破壞性等特點,在工程中很難予以預防.本研究基于動力學與能量作用原理,通過固有振動頻率等振動特征指標實現對邊界剪切彈性系數的計算.在物理模型試驗中,應用多普勒激光測振儀對巖爆體破壞全過程進行遠程振動特征監測.試驗得出,結構面強度的非協調弱化效應是巖爆發生的必要條件,結構面弱化的時空差異是發生瞬時性巖爆還是遲滯型巖爆的主要因素.當結構面弱化較慢時,則為遲滯型巖爆,反之,則為瞬時性巖爆.基于固有振動頻率可識別巖體結構面的弱化速率,巖爆發生全過程中,結構面的總耗散能僅為賦存彈性能的0.06%,使得幾乎所有的彈性動能都將轉化為沖擊動能,表現為巖爆體以高速的形式彈射出來.基于頻率下降速率等監測數據分析,可識別巖爆結構面強度的非協調弱化特征.因此,增加固有振動頻率等動力特征監測指標,無疑會進一步提高對巖爆孕育演化特征規律的認識,并在地下空間工程巖爆預警監測方面發揮重大作用.

     

    Abstract: Prediction and prevention of rock burst in project is difficult because of its paroxysm and sudden destructiveness. Determining how to predict the time, place, and intensity of rock burst is one of the main engineering problems that must be solved via geotechnical engineering. Increasing number of experts from the field of underground mining and construction are applying new monitoring techniques and methods to study rock burst for its effective prediction. In the model experiment, the entire process of structuretype rock burst was remotely monitored via the laser Doppler vibrometer. Based on the dynamic theory and energy conservation law; the natural vibration frequency was used to analyze the elastic coefficient of the shear plane. The experimental results show that the incompatible weakness of structural plane is a necessary condition for the occurrence of rock burst, and the spatiotemporal difference of the structural plane strength is the main factor that determines the immediate or the time-delayed rock burst. Slow weakening of the structure causes time-delayed rock burst, whereas rapid weakening causes immediate rock burst. During the whole process of rock burst, the weakening rate of rock mass structure is determined using the natural vibration frequency, and the dissipated energy of the structure occupies merely 0.06% of the rock elastic energy. Thus, most of the elastic energy is released in the form of kinetic energy, and the rock is ejected with high velocity. Furthermore, the incompatible weakening characteristics of rock burst structural planes can be analyzed using the analysis of the frequency decline rate. Therefore, the new monitoring index of dynamic characteristics such as natural vibration frequency improves the understanding of evolution characteristics of rock burst and plays a significant role in the early warning of rock burst in underground engineering.

     

/

返回文章
返回
<th id="5nh9l"></th><strike id="5nh9l"></strike><th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th><strike id="5nh9l"></strike>
<progress id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"><noframes id="5nh9l">
<th id="5nh9l"></th> <strike id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span>
<progress id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span><strike id="5nh9l"><noframes id="5nh9l"><strike id="5nh9l"></strike>
<span id="5nh9l"><noframes id="5nh9l">
<span id="5nh9l"><noframes id="5nh9l">
<span id="5nh9l"></span><span id="5nh9l"><video id="5nh9l"></video></span>
<th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th>
<progress id="5nh9l"><noframes id="5nh9l">
259luxu-164