水岩作用下露天坑边坡岩石蠕变试验分析

发布时间：2018-02-06 05:19

本文关键词： 水岩作用露天矿坑岩石力学蠕变试验蠕变规律　出处：《长江科学院院报》2017年03期 　论文类型：期刊论文

【摘要】：为了探究水位升降对边坡长期稳定的影响,选取莱州仓上露天坑边坡岩石,对经历不同饱水-失水循环次数的岩样进行了三轴蠕变试验。通过分析SγJH蠕变应变-时间曲线及蠕变速率曲线,探究边坡岩石经历饱水-失水循环作用后的蠕变性质变化。进一步利用电镜对经历不同循环次数的SγJH岩样进行扫描,从细微观角度分析了水岩作用对矿坑边坡岩石损伤机理。结果表明:随饱水-失水循环次数增加,相邻循环次数下的SγJH轴向蠕变应变最多提高31%,侧向提高33%;SγJH-15后瞬时弹性应变较SγJH-0提高了54.3%,相邻荷载等级下蠕变应变提高24.3%,蠕变总应变可达到三轴压缩极限应变的80%以上。经历饱水-失水循环后,SγJH稳态蠕变速率不再为0,而是随饱水-失水循环次数增加不断提高,SγJH-15第5级荷载作用下稳态流变速率达到29.2×10~(-6)/h;在施加各级轴向荷载的瞬时,初期蠕变速率加速度亦有所提升。水岩作用下岩石力学性质变化机理研究方面,由于SγJH内部结构的非均质性,在饱水-失水循环作用下岩样发生微观弱化和破裂,使得原有的应力平衡被打破,从而造成岩石变形曲线产生了不规则波动和突变。
[Abstract]:In order to explore the impact of water level rise and fall on the long-term stability of the slope, Laizhou Cangshang open-pit slope rock. Triaxial creep tests were carried out on rock samples with different cycles of saturated water and water loss. The creep strain-time curves and creep rate curves of S 纬 -JH were analyzed. The creep properties of slope rock were investigated after the saturated water loss cycle. The S 纬 JH samples with different cycles were scanned by electron microscope. The mechanism of rock damage caused by water-rock action on pit slope is analyzed from the microscopic point of view. The results show that the axial creep strain of S 纬 -JH increases by up to 31% with the increase of water-saturated cycle times. Lateral increase of 33%; The instantaneous elastic strain after S 纬 JH-15 is 54.3 higher than that of S 纬 JH-0, and the creep strain increases by 24.3% under adjacent loads. The total creep strain can reach more than 80% of the ultimate strain of triaxial compression. The steady creep rate of S 纬 JH is no longer 0, but increases with the increase of the cycle times of saturated water and water loss. The steady state rheological rate of S 纬 JH-15 under the fifth order load is 29.2 脳 10 ~ (-1) ~ (-6) / h; The acceleration of initial creep rate is also increased with the application of various axial loads. The mechanism of rock mechanical properties under the action of water rock is studied because of the heterogeneity of the internal structure of S 纬 JH. The microcosmic weakening and rupture of rock samples under the action of saturated water-loss cycle make the original stress balance to be broken resulting in irregular fluctuation and abrupt change of rock deformation curve.
【作者单位】：山东科技大学矿山灾害预防控制重点实验室-省部共建国家重点实验室培育基地;山东科技大学矿业与安全工程学院;临沂大学建筑学院;
【基金】：国家自然科学基金煤炭联合基金重点项目(U1261205);国家自然科学基金面上项目(51574158)
【分类号】：TU45

【相似文献】