针对五阳矿76#-2厚煤层专用回风巷道底板经常发生大变形破坏,通过研究厚煤层巷道底鼓机制及控制原理,提出对厚煤层巷道底板进行中、深部加固的治理思想控制底鼓。采用FLAC3D模拟了不同支护方法对底板的作用,研究表明:底板无支护,底板变形量为1.3~1.6 m,在采动应力扰动下,底板破坏范围将逐渐增大;采用锚网浆支护,底板塑性破坏区相应减少,但受到应力扰动的影响,底鼓量为0.7~1.0 m,仍不能满足生产需要;采用高强度锚索束分区注浆及混凝土条块耦合支护(锚混凝土浆支护),底板围岩塑性区明显缩小,底鼓量仅为0.24~0.38 m,达到控制底板变形的要求。通过对锚混凝土浆支护方法进行工程试验,结果表明:巷道两帮收缩量226 mm,底鼓量283 mm,分别减少了56.5%,83.4%,有效控制了厚煤层巷道底板的较大变形。
In view of the frequent large deformation failures of the extraction roadway floor in thick seam 76#-2 in Wuyang mine,we proposed the prevention concept of medium and deep strengthening in thick seam roadway to control floor heave,through studying on the mechanism and control method of the floor heave in thick seam roadway.Additionally,the effects to the floor under different supporting ways were simulated by FLAC3D software.The results show that the floor deformation without supporting is 1.3~1.6 m,but the floor damage zone will be extended gradually under the mining stress disturbance.The floor plastic zone will be reduced correspondingly by the support of anchor coupled with the grouting,but the maximum value of floor deformation amount to 0.7~1.0 m when influenced by mining stress,and the roadway still can't meet the production needs.By using the combined support of a branch of high-strength anchors coupled with concrete block and grouting,the plastic zone in floor surrounding rock will be reduced significantly,and the floor heave is only 0.24~0.38 m,which has met the requirements to control the floor deformation.Through the engineering tests of the combined support technique,the result shows that the two sides'displacement and floor heave of the roadway are 226 mm and 283 mm,which are reduced by 56.5% and 83.4%,respectively.Thus,the large-scale deformation of roadway floor in thick seam has been controlled effectively.