基于加卸载速度影响下的含瓦斯煤力学及渗透特性实验研究  

Experimental study of mechanical and permeability characteristics of coal with methane containing due to different loading-unloading speeds

作　　者：蒋长宝[1] 俞欢[1] 段敏克 李广治[1] 

机构地区：[1]重庆大学煤矿灾害动力学与控制国家重点实验室资源及环境科学学院,重庆400030

出　　处：《采矿与安全工程学报》2017年第6期1216-1222,共7页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(51674048;51204217);重庆市科技计划项目(cstc2015jcyjA90009)

摘　　要：利用自行研制的含瓦斯煤热流固耦合三轴伺服渗流实验装置,以四川白皎煤矿原煤为研究对象,进行了基于加卸载速度影响下的含瓦斯煤力学及渗透特性实验研究。研究结果表明:不同加卸载速度影响下煤样的强度随初始静水压力的升高而呈对数关系升高,随加卸载速度的加快而呈幂函数关系降低;加卸载煤样破坏形式以剪切破坏为主,部分煤样表现出张剪复合破坏形式;加卸载煤样渗透率并不全部表现为先减少后增加的"V"型变化规律,在煤样呈张剪复合破坏形式的情况下渗透率表现为先减少后增加且在峰值点附近(93.65%~96.65%)有一个下降阶段直至破坏后迅速上升的"W"型变化规律;与无瓦斯加卸载煤样相比,有瓦斯加卸载煤样强度更低、破坏轴向应变更小、破坏瞬间变形模量变化率更大、扩容现象更明显。Using the self-made triaxial servo-controlled seepage experimental equipment for ther-mo-hydro-mechanical coupling of coal with methane containing, the experimental studies of mechanical and permeability characteristics of such coal samples taken from Baijiao mine are performed under dif-ferent loading-unloading speeds. The results show that： the strength of coal under different load-ing-unloading speeds increases logarithmically with increasing initial hydrostatic stress and decreases with increasing loading-unloading speeds presenting the power function relationship; The major failure form of loading-unloading coal is the shear failure. Some coal samplers show the tenso-shear failure mode. Not all of loading-unloading coal samples show decreasing firstly and then increasing later as＂V＂ shape of the permeability change rule. Under the tenso-shear composite failure, there is a change rule of the permeability that increases after decreasing followed by a declined stage around the peak point and shows as a ＂W＂ shape. Compared with coal samples without methane containing, the strength is lower. The axial strain is smaller when it fails. The rate of deformation modulus is bigger at the moment of failure and the phenomenon of dilatancy is more obvious.

关 键 词：含瓦斯煤 加卸载 强度 渗透率 破坏形式 

分 类 号：TD712[矿业工程—矿井通风与安全]