节理岩体内砂浆锚杆锚固力演化特征试验研究  

Experimental study on anchoring force evolution characteristics of mortar anchor in joint rock mass

作　　者：靖洪文[1] 朱谭谭 苏海健[1] 尹乾[1] 赵洪辉[1] 韩观胜 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116

出　　处：《煤炭科学技术》2017年第1期16-21,共6页Coal Science and Technology

基　　金：国家重点基础研究发展计划(973计划)资助项目(2013CB036003);国家自然科学基金资助项目(51374198);中国矿业大学大学生创新创业基金资助项目(201509)

摘　　要：为了研究节理岩体内砂浆锚杆锚固力的演化特征,在锚固体内预制了不同尺寸和位置的节理,通过室内拉拔试验,考察了节理开度和节理-表面距离对锚固系统锚固力的影响。研究结果表明:节理-表面距离对锚固系统破坏形态基本没有影响,而随着节理开度的增大,锚固系统破坏形式由锚杆屈服拉断破坏逐渐演化为锚杆、砂浆和锚固体接触面剪切破坏,其中有66.67%表现为锚杆-砂浆接触面破坏,仅有33.33%表现为砂浆-锚固体接触面破坏;节理开度对锚杆锚固段应力分布和系统承载能力影响显著,随节理开度的增大,锚固系统承载力逐渐减小,而节理-表面距离越大,锚固系统承载能力越强;完整锚固体锚杆锚固段轴向应力随深度的增大逐渐减小,在节理附近,含节理锚固体锚杆轴向应力基本保持不变,深度大于节理-表面距离时,锚杆轴向应力大于同位置完整锚固体锚杆轴向应力。In order to investigate the evolution of anchoring force of mortar anchor in joint rock mass,indoor pull-out test of anchorage vol- ume with pre-joints of different sizes and locations was conducted, and the influence of joint aperture and the joint-surface distance on the anchoring force of the whole system was also studied. The results show that the joint-surface distance has little effect on the uhimate fail- ure mode of the anchoring system, while with the increasing joint aperture, the ultimate failure mode of the anchoring system changes gradu- ally from the yield and tensile failure of the anchor to shear failure at the contact faces between the anchor, mortar and the anchorage vol- ume, and in which 66. 67% of the shear failure presents the interface failure between the anchor and the mortar, only 33.33% of the shear failure shows the interface failure between the mortar and the anchorage volume. Joint aperture has significant influence on the stress dis- tribution of the anchorage section and the bearing capacity of the whole system. The bearing capacity of the anchorage system decreases gradually with the increasing joint aperture, while increases gradually with the rise of the joint-surface distance. Axial stress of the anchor- age section in intact anchorage volume decreases gradually with the increasing depth, while the axial stress of the anchor near the joints in flawed anchorage volume maintains basically stable, and the axial stress of anchor is greater than that of the intact anchorage volume in the same position when the depth is greater than the joint-surface distance.

关 键 词：节理岩体 砂浆锚杆 锚固力 荷载传递 

分 类 号：TD353[矿业工程—矿井建设]