不同煤体结构煤岩抗拉强度测试

Tensile strength test of coal and rock with different coal structure

  • 摘要: 煤岩作为一种特殊的沉积岩,在形成后大多会经历多期构造运动,造成煤体结构的多样性,很难直接采用某一种方法进行不同煤体结构煤岩抗拉强度测试。为获得不同煤体结构煤岩抗拉强度,以淮北矿业(集团)有限责任公司孙疃煤矿10煤为研究对象,分别采用巴西劈裂试验和点荷载试验对不同煤体结构煤岩进行了测试。结果表明:① 通过巴西劈裂试验测得原生结构煤、碎裂煤平均抗拉强度分别为1.174,0.710 MPa;通过点荷载试验测得原生结构煤、碎裂煤、碎粒煤、糜棱煤平均点荷载强度分别为0.368,0.248,0.112,0.041 MPa。② 煤的点荷载强度与抗拉强度具有较好的线性相关性,对点荷载强度与抗拉强度测试结果进行线性拟合,获得点荷载强度与抗拉强度的转换关系式,进而根据关系式计算得到碎粒煤、糜棱煤平均抗拉强度分别为0.345,0.126 MPa。③ 从原生结构煤到碎裂煤、碎粒煤再到糜棱煤,即随着煤体结构破坏程度增加,煤岩抗拉强度显著降低,且下降幅度呈逐渐增大趋势。

     

    Abstract: Coal and rock, as a special sedimentary rock, mostly undergoes multiple phases of tectonic movements after its formation, resulting in the diversity of coal structures. Therefore, it is difficult to directly use a certain method to test the tensile strength of coal and rock with different coal structures. In order to obtain the tensile strength of coal and rock with different coal structures, taking No.10 of Suntuan Coal Mine of Huaibei Mining (Group) Co., Ltd. as an example, the Brazilian splitting test and the point load test are conducted on coal and rock with different coal structures. The results show the following three points. ① The average tensile strengths of primary structure coal and fractured coal measured by Brazilian splitting test are 1.174 and 0.710 MPa respectively. The average point load strengths of primary structure coal, fractured coal, crushed coal and mylonite coal measured by point load test are 0.368, 0.248, 0.112 and 0.041 MPa respectively. ② The point load strength and tensile strength of coal have a good linear correlation. The point load strength and tensile strength test results are linearly fitted to obtain the conversion equation between the point load strength and the tensile strength. According to the equation, the calculated average tensile strengths of crushed coal and mylonite coal are 0.345 and 0.126 MPa respectively. ③ From primary structure coal to fractured coal, crushed coal and cinder coal, the tensile strength of coal rock decreases significantly with the increase of the damage degree of coal structure, and the decline tends to increase gradually.

     

/

返回文章
返回