砂浆与岩石黏结性能的试验研究

砂浆与岩石的黏结性能,对岩土工程中的山体支护效果、结构工程中抗浮锚杆的极限抗拔力及混凝土材料基本力学性能起着至关重要的作用。通过灌注于岩石块体内的砂浆圆柱体压出试验得到了砂浆与岩石界面的黏结滑移本构关系,进而研究了砂浆等级、砂浆柱体直径及黏结长度对界面的黏结强度和残余摩擦应力的影响。结果表明:砂浆与岩石界面的黏结滑移曲线由弹性上升段、软化下降段和水平摩擦段3部分组成。而且界面的黏结强度与残余摩擦应力随砂浆等级的提高而增大。但对相同等级的砂浆而言,界面黏结强度与残余摩擦应力随砂浆柱体直径的增大而减小。此外,界面的平均黏结应力随黏结长度的增加而减小。

Experimental study on the bond performance between mortar and rock

The bond performance between mortar and rock has much influence on the efficiency of hill slope support in geotechnical engineering,the pull-out capacity of anti-floating anchor in civil engineering and the mechanical properties of concrete.A push-out test of mortar cylinder from rock block is performed and the constitutive relationship between the bond stress and slip at the mortar-rock interface is obtained.Moreover,the effects of the mortar strength,the diameter of mortar cylinder and the bond length on the bond strength and the residual frictional stress are analyzed.Results show that the bond stress-slip curve includes an elastic ascending part,a softening descending part and a residual frictional portion,and both the bond strength and the residual frictional stress increase with the mortar strength.However,the two interfacial parameters decrease with the increasing of the mortar diameter.Besides,the average bond stress decreases with the increasing of the bond length.