1.Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines,Hunan University of Science and Technology,Xiangta ,China；2. School of Resource & Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan ,China

为了研究薄煤层开采下松散煤岩体巷道不均匀破坏问题，以松散煤岩体回采巷道为工程背景，对松散煤岩体组合试件进行了一系列单轴试验研究。试验结果表明：松散煤岩组合体试件的平均单轴抗压强度介于全岩试件与全煤试件强度之间（2.19~3.37 MPa）。不同加载速率试验条件下，松散煤岩组合体与全煤试件的试验结果与一般完整硬岩有较大区别，试样平均单轴抗压强度和平均残余强度没有增加，反而随加载速率增加而减小（1 MPa左右）。松散煤岩组合体试件存在着一个加载速率的临界值效应，力学特性呈现出先减小后增加的规律。组合体试件松散煤体和岩体环向应变最大值发生在单轴应力加载至峰值强度附近。从煤、岩环向应变等值线分布云图来看，岩体在受载全过程环向应变较为平稳，而煤体应变波动敏感较大，煤体部位环向应变幅度范围明显大于岩体部位的环向应变值。可见，松散煤岩组合体试件整体变形呈非线性，二者不均匀破坏明显。

In order to study the problem of uneven failure of roadway in loose coal and rock mass under thin seam mining,a series of uniaxial tests of loose coal and rock composite specimens are carried out based on the engineering background of loose coal and rock mining roadway. The test results show that the mean uniaxial compressive strength (MUCS) of loose coal and rock composite specimens is between that of full rock specimens and full coal specimens (2.19 ～ 3.37 MPa). With the increase of constant loading rate,the test results of loose coal-rock composite specimens and full coal specimens are quite different from those of ordinary hard rock specimens:the MUCS and MRS (mean residual strength) of loose coal-rock composite specimens do not increase,but decrease with the loading rate (about 1 MPa). There exists a critical value effect of loading rate for loose coal-rock composite specimen,and the mechanical properties show a law of decreasing first and then increasing. From the contour map of the circumferential strain of the coal part and rock part,the circumferential strain of rock part is relatively stable during the whole loading process,while the strain of coal part fluctuates greatly. The maximum and minimum range of coal part circumferential strain is larger than that of rock part. It can be seen that the overall deformation of the loose coal and rock composite specimen is nonlinear,and the uneven failure between the two parts are obvious.