煤层顶底板岩石点荷载强度与拉压强度对比试验研究

 利用自主研制的点荷载仪，通过室内对煤矿顶底板常见岩性岩石进行点荷载试验、单轴抗压试验、抗拉试验对比分析，研究由点荷载强度快速准确确定单轴抗压强度及抗拉强度的方法。试验结果表明：点载荷强度较低的粗砂岩极易受到加载速率和加载方向影响，其预测值与实际值的误差相对较大；而对于点荷载强度较大的岩石，3种强度的线性相关性较高。点荷载试验的应用，为煤矿顶底板岩石强度确定及岩体分类提供了重要依据。

COMPARATIVE EXPERIMENTAL RESEARCH ON POINT LOAD STRENGTH,UNIAXIAL COMPRESSIVE STRENGTH AND TENSILE STRENGTH FOR ROCKS IN ROOF AND FLOOR OF COAL SEAM

The comparative experimental research on point load strength，uniaxial compressive strength and tensile strength of rocks in the roof and floor of coal seam was carried out by the self-made point load tester to obtain a quick and accurate method to predict uniaxial compressive strength and tensile strength through point load strength. The results show that the samples of coarse stone with lower point load strength are greatly influenced by loading rate and loading direction；so the errors of the predictive values and actual values are quite large. For the rock samples with larger point load strength，their linear correlations are higher among strengths of three types. It provides an important basis for the determination of rock strength and rock mass classification in the roof-floor of coal seam.