节理岩体内砂浆锚杆锚固力演化特征试验研究

发布时间：2019-03-04 09:23

【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。
[Abstract]:In order to study the evolution characteristics of anchoring force of mortar bolt in jointed rock mass, the joints of different sizes and positions were prefabricated in the Anchorage body. The effects of joint opening and joint-surface distance on anchoring force of Anchorage system were investigated by pull-out test in laboratory. The results show that the joint-surface distance has no effect on the failure form of the Anchorage system, but with the increase of the joint opening, the failure form of the Anchorage system gradually evolves from the yield tensile failure of the bolt to the anchor rod. The shear failure of mortar and anchor solid interface is 66.67%, only 33.33% is mortar-anchor solid interface failure. With the increase of joint opening, the bearing capacity of the anchoring system decreases gradually, and the greater the joint-surface distance, the stronger the bearing capacity of the anchoring system. The axial stress of anchoring section of intact anchor decreases with the increase of depth. Near the joint, the axial stress of anchor rod with jointed solid remains basically unchanged, and when the depth is greater than the distance between joint and surface, the axial stress of anchor bar with joint is almost unchanged, when the depth is greater than the distance between joint and surface. The axial stress of anchor rod is greater than the axial stress of solid anchor rod in the same position.
【作者单位】：中国矿业大学深部岩土力学与地下工程国家重点实验室;
【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)
【分类号】：TD353.6

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