锚固参数对地震作用下岩质边坡锚固界面剪切作用影响的数值分析

发布时间：2018-02-02 22:58

本文关键词： 锚固岩质边坡锚固参数锚杆-砂浆界面砂浆-岩体界面界面剪应力永久位移　出处：《煤炭学报》2017年10期 　论文类型：期刊论文

【摘要】：基于FLAC~(3D)建立锚固岩质边坡数值分析模型,并用优化的cable单元建模分别模拟分析锚杆-砂浆界面上和砂浆-岩体界面上的剪切作用,通过改变全长黏结锚杆的锚固参数(锚固角、锚固段长度、锚杆竖向间距、锚杆直径、锚孔直径),对地震作用下锚固岩质边坡锚固界面上的剪应力及动力响应规律进行研究。研究发现:在地震作用下,随着锚固角的增大,锚固界面上的峰值剪应力减小,边坡永久位移增大;当锚杆在结构面两侧的长度相等时锚杆界面的锚固作用最大化;当锚杆竖向间距减小,峰值剪应力和边坡永久位移均减小;随锚杆和锚孔直径的增大,峰值剪应力和边坡永久位移总体呈减小的趋势。在考虑安全性、经济性的前提下,建议适当减小锚固角和锚杆竖向间距,保持锚杆拉拔段与锚固段长度相等,锚杆和锚孔直径保持合理的比值。该研究可为相关理论、试验研究和锚固边坡抗震设计提供参考。
[Abstract]:The numerical analysis model of Anchorage rock slope is established based on FLACX / 3D), and the shear action on the interface between bolt and mortar and on the interface of mortar and rock is simulated and analyzed by the optimized cable element model, respectively. The anchoring parameters (Anchorage angle, length of anchoring section, vertical spacing of anchor rod, diameter of anchor rod, diameter of anchor hole) were changed. The shear stress and dynamic response at the Anchorage interface of Anchorage rock slope under earthquake are studied. It is found that the peak shear stress at the Anchorage interface decreases with the increase of Anchorage angle. The permanent displacement of slope increases; When the length of the bolt on both sides of the structure plane is equal, the Anchorage effect of the bolt interface is maximized. The peak shear stress and the permanent displacement of the slope decrease when the vertical spacing of the bolt decreases. With the increase of the diameter of anchors and anchors, the peak shear stress and the permanent displacement of the slope decrease generally. Considering the safety and economy, it is suggested that the anchoring angle and the vertical spacing of the anchors should be reduced appropriately. The length of the bolt drawing section is equal to that of the anchor section, and the diameter of the anchor rod and the anchor hole keeps a reasonable ratio. This study can be used as a reference for the relevant theory, experimental study and seismic design of the anchoring slope.
【作者单位】：兰州大学土木工程与力学学院;河南城建学院土木与交通工程学院;
【基金】：国家自然科学基金面上资助项目(41372307,51478065) 甘肃省建设科技攻关资助项目(kjxm2014-42)
【分类号】：TU457;TU476
【正文快照】： 锚固是边坡治理的常用方法,其结构巧、施工易、造价低、效果好。通过调研汶川地震边坡的破坏现象,还发现锚杆锚固边坡也具有较好的抗震性能,而目前锚固边坡动力稳定性研究远落后于工程实践,因此急需针对锚杆锚固的核心问题——锚固界面剪切作用进行研究。前人对静力荷载下的锚

【相似文献】