全长锚固锚杆支护破断行为数值计算  

Numerical Study on the Rupture Behaviour of Fully Grouted Rock Bolts

作　　者：陈见行 代鑫 CHEN Jianhang;DAI Xin(State Key Laboratory of Intelligent Coal Mining and Strata Control,Beijing 100013,China;School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]煤炭智能开采与岩层控制全国重点实验室,北京100013 [2]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《湖南科技大学学报(自然科学版)》2025年第1期8-14,共7页Journal of Hunan University of Science And Technology:Natural Science Edition

基　　金：煤炭智能开采与岩层控制全国重点实验室开放基金资助项目(SKLIS202422);国家自然科学基金资助项目(52034009,52174093)。

摘　　要：数值计算广泛应用于锚杆支护力学性能研究中,其中三维有限差分软件FLAC^(3D)含有能够模拟支护的结构单元,常用于巷道支护的模拟研究中.但该软件中锚结构单元没有考虑杆体破断行为,模拟效果与实际情况有较大出入.因此本文采用桩结构单元模拟锚杆,首先对比锚结构单元和桩结构单元力学特点,发现桩结构单元能够模拟杆体破断行为,且模拟结果与物理试验结果一致:随后研究拉伸破断应变对锚杆支护性能的影响,发现无围压和有围压条件下拉伸破断应变增加,导致锚杆破断时对应拉拔位移增加,并通过线性拟合得到两者间关系式.此外,杆体破断前锚杆轴力从拉拔端向自由端逐渐递减,杆体破断后锚杆轴力迅速下降至零附近.Numerical calculation is widely used in studying the mechanical performance of rock bolting.Among them,the three-dimensional finite dfference software FLAc^(3D) has the structure elements that can simulate the rock reinforcement.Therefore,it is widely used in numerical investigation of the roadway support.However,in this program,the cable element neglects the rupture behaviour of bolts.This leads to the significant difference between simulation and physical test results.Therefore,this paper uses the pile elements to simulate rock bolts.First,the mechanical performance between cable and pile elements is compared.It is found that the pile elements can simulate the bolt rupture behaviour.Moreover,there is a close match between simulation and physical test results.Then,the influence of the tensile failure strain on the bolting performance is studied.It shows that no matter whether the confinement is applied or not,the pullout displacement where rupture occurrs,increases with the tensile failure strain.Linear regression is conducted to acquire the relationship between them.Additionally,before rupture,the axial load in the bolt decreases gradually from the loaded end to free end.However,after rupture,the axial load in the bolt decreases rapidly to around zero.

关 键 词：锚杆支护 拉拔模拟 破断行为 拉伸破断应变 

分 类 号：TD353[矿业工程—矿井建设]