双孔洞倾角对红砂岩抗拉强度及破坏特征影响的试验研究

Experimental study on the effect of dip-angle on tensile strength and failure characteristics of red sandstone

为了研究双孔洞倾角对红砂岩抗拉强度及破坏特征的影响,对含不同双孔洞倾角的红砂岩进行单轴抗拉试验,通过高速摄像机记录其破坏过程,并结合ANSYS数值模拟软件分析其破坏过程中应变场演化规律。进一步探究双孔洞倾角对红砂岩抗拉强度及破坏特征的影响。结果表明:随双孔洞倾角的增大,(1)红砂岩的抗拉强度呈现先降低后升高再降低的变化趋势;(2)试样破坏模式由裂纹贯穿单孔洞破坏向裂纹沿着单孔洞边缘贯穿破坏再向裂纹贯穿双孔洞破坏;(3)应变集中区逐渐将双孔洞与试样边缘连通,且最大应变表现出与抗拉强度相同的变化规律。

In order to study the effect of the dip-hole Angle on the tensile strength and failure characteristics of the red sandstone,uniaxial tensile test was carried out on the red sandstone with different dip-hole Angle,its failure process was recorded by high-speed camera,and the evolution law of the strain field during the failure process was analyzed by combining with ANSYS numerical simulation software.The effect of dip-hole Angle on the tensile strength and failure characteristics of red sandstone was further studied.The results show that the tensile strength of red sandstone decreases first,then increases and then decreases with the increase of the dip-hole Angle.(2)The sample failure mode is formed by the crack through the single hole and then the crack through the double hole along the edge of the single hole.(3)The concentration area of strain gradually connects the double-hole with the edge of the sample,and the maximum strain shows the same change law as the tensile strength.