砂浆锚杆加固效果的等效数值模拟方法研究  

An equivalent numerical method for evaluating the reinforcing effectiveness of grouted bolts

作　　者：陈东方[1] 冯夏庭[2] 徐鼎平[2] 江权[2] 刘国锋[2] 简崇林[3] 

机构地区：[1]东北大学深部金属矿山安全开采教育部重点实验室,辽宁沈阳110819 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [3]中国长江三峡集团公司,北京100038

出　　处：《岩土力学》2015年第4期1195-1204,共10页Rock and Soil Mechanics

基　　金：国家自然科学基金重点项目资助(No.11232024);国家自然科学基金国际合作重大项目资助(No.41320104005);国家自然科学基金(No.51309219)

摘　　要：针对常规数值模拟计算无法有效地反映锚杆对围岩的加固效果的缺陷,结合岩体变形在锚杆中产生的支护压力计算公式,提出了一种简单、有效的砂浆锚杆加固等效数值模拟方法。该方法首先在有锚杆支护隧道开挖的计算结果中提取每根锚杆的最大轴力;然后根据该轴力值按锚杆支护压力公式计算其所产生的等效均布力;最后将该均布力施加到相同计算工况下无锚杆支护的围岩表面进行模拟计算。将该方法应用于锦屏二级水电站地下厂房枢纽洞室及乌东德水电站4#导流洞0+550 m断面的开挖与支护计算,通过与现场实测数据对比,结果表明,该方法能较好地模拟锚杆支护对围岩的加固效果,其模拟结果可为隧洞的施工与支护设计提供可靠的参考依据。Because conventional numerical methods fail to evaluate the effectiveness of grouted bolts in reinforcing the surrounding rockmass, a simple and effective equivalent numerical method, with combination of a formulation for the bolt supporting pressure induced by rockmass deformation, is proposed for this purpose. In this method, the maximum axial force of each bolt is first determined by numerically simulating the bolt-supporting tunnel excavation. The obtained maximum axial force is then used to calculate the equivalent force distributing along the rock bolt by using the formulation of the bolt supporting pressure. Finally, the excavation process without bolt supporting is simulated by applying the equivalent distributing force to the surrounding rockmass surface. This method is applied to calculate the excavation and support of the underground powerhouse at Jinping Ⅱ hydropower station and the diversion tunnel #4（section 0＋550 m） at Wudongde hydropower station. By comparing the calculation results with the field measured data, it is found that the proposed method can well address the effectiveness of grouted bolts in reinforcing the surrounding rock, and the simulation results can provide reference for tunnel construction and support design.

关 键 词：砂浆锚杆 加固效果 数值模拟 支护设计 

分 类 号：TU443[建筑科学—岩土工程]