【作者】 王猛；

【导师】 李义；

【作者基本信息】 太原理工大学 ， 安全技术及工程， 2012， 硕士

【摘要】 目前岩土工程中常用的锚杆锚固质量检测方法大多是破坏性的,会破坏锚固体系的内部结构,所以,寻求一种可靠、快速、经济、无损的检测方法的需求也日益迫切。本文对应力波在弹性杆中的传播规律以及不同约束条件下的传播规律进行了理论研究。通过实验室模拟实验对应力波的传播理论进行了验证；通过对煤矿井下现场锚杆的测试与实验室模拟实验进行对比,验证了应力波法锚杆锚固质量无损检测技术的可行性。本文所做的主要研究工作如下：①首先介绍了锚杆支护理论,研究了应力波在锚杆体系中的传播规律以及应力波在锚固体系中的能量的衰减和分配规律,为应力波法锚杆锚固质量无损检测技术提供了理论依据。②锚杆锚固质量的优劣可以用有效锚固长度、衰减系数、幅值比、频率比、动刚度和基频这几个指标进行评价。实验结果表明固结波速的大小反映了锚杆与锚固介质的粘结强度,固结波速可以从另外的方面反映锚杆的锚固质量。③通过实验室模拟实验对应力波在锚杆自由段和锚固段的波速进行了研究,对实测信号进行时域分析发现锚杆自由段的波速不随锚杆所承受荷载的变化而变化；通过对实测信号进行频域分析,找出不同荷载作用下的测试信号的基频,利用ORIGIN软件拟合出测试信号的荷载—基频函数,发现两者的确呈三次幂函数关系。④利用应力波锚杆锚固质量无损检测法,对国阳二矿71312回风配巷中的锚杆进行了检测,并对锚固质量进行了评价,验证了应力波法锚杆锚固质量无损检测技术的可行性。更多还原

【Abstract】 At present, the methods of testing technology for bolt anchoring quality commonly used in geotechnical engineering field are mostly destructive, which can destroy the internal structure of rock bolts system, thus, the demand for seeking a reliable, rapid, economic and nondestructive testing method for bolt anchoring quality is becoming increasingly urgent.This paper conducts a theoretical study on the propagation law of stress waves in elastic rods and the propagation law of elastic rods under different constraints. Through laboratory simulation experiments, this author verifies the propagation theory of the stress wave; Through contrasting spot tests for rock bolts in coal mine with the laboratory simulation experiments, so as to verify the feasibility of the stress wave nondestructive testing technology for bolt anchoring quality. The research works this author carries out are as follows:1. Firstly, the author introduces the bolt support theory, studies the propagation law of stress waves in the anchor system, the energy attenuation and distribution of the stress wave in rock bolts system, thereby providing theoretical basis for the stress wave nondestructive testing technology for bolt anchoring quality.2. These indexes (including effective development length, attenuation coefficient, amplitude ratio, frequency ratio, dynamic stiffness and fundamental frequency) can evaluate the fulu of bolt anchoring quality. Experimental results show that the concretion wave speed size reflects the cohesive strength of rock bolt and anchoring medium, the concretion wave speed can reflect the anchoring quality of rock bolt from the other aspects.3. By simulation experiment in laboratory, the author studies the wave velocity of stress wave in the free segment of rock bolt and in the anchoring segment. The author conducts time-domain analysis on test signal, so as to show that the wave velocity in the free segment of rock bolt doesn’t vary with the change of the load on the rock bolt. The concretion wave speed tends to increase with the increase of the load on the rock bolt. Through conducting frequency-domain analysis on test signal, so as to find out the fundamental frequency of the test signal under different loads, using ORIGIN software to fit the load-fundamental frequency function, the author finds that it really presents three times a power function relation.4. Using the stress wave nondestructive testing method for bolt anchoring quality, the author detects the rock bolt in71312roadway in GuoYang2# Mine and evaluates the quality of bolt anchoring, verifing the feasibility of the stress wave nondestructive testing technology for bolt anchoring quality.更多还原