Research On Design Principle And Method Of Acoustic Excitation Of Rock Bolt Axial Force Monitoring Device

This paper aims to study a kind of rock bolt axial force monitoring device.As rock soil anchoring technology is an important way of bolting support, due to the strengthening of the roadway surrounding rock, significantly improve the stability of surrounding rock, and it has a low support cost, low labor intensity,improve the working environment and conditions for safe production etc, has become the world of mine roadway supporting form of support, but also widely used in slope stability, deep foundation pit, maintenance, tunnel and hole branch support, dam abutment anchoring engineering. With the passage of time, due to the continuous exploitation of the mineral and geological condition changes and other factors, the stability of surrounding rock will change, resulting in the failure of anchor, roadway caused by the collapse, which requires timely adjust the support design, in order to adapt to the change of surrounding rock conditions, so the bolt supporting quality monitoring has become a key, which is very important for the axial force of the anchor.After analyzing the present situation of the bolt axial force monitoring device at home and abroad, this paper according to the shortcomings of thecurrent monitoring device, proposed a using acoustic excitation for nondestructive monitoring apparatus and method of axial force of rock bolt,namely the use of acoustic structure coupling and the sound spectrum analysis,through the ear to listen to the size and frequency of sound, to judge the bolt under the magnitude of the axial force. Firstly, theoretical analysis, in order to realize the monitoring of the axial force of bolt, according to contain prestressed bolt by stress state and analyzed from the relation theory of thin plate vibration theory and prestressed and modal, supplemented by acoustics theory, for realizing the monitoring principle, laid the theoretical basis. And put forward a proposal, in order to realize the monitoring of the axial force of bolt, according to the application characteristics and application of anchor design, three schemes for model, respectively of the three schemes in mechanics, modal and acoustic field were calculation and analysis, draw the square bolt axial force monitoring device is the best scheme. In the final analysis, components, is the impact on performance parameters of monitoring devices of various components and parts,of the supporting column for the pressure calculation of the stability of the rod,of plate thickness variation, bearing body size changes, resonance board thickness, size and material of different, respectively, were calculated and analyzed in detail in the paper.This paper presents a using acoustic excitation device and a method for rock bolt axial force monitoring, first of all in theory are analyzed, the monitoring principle in theory of the feasibility study; then use ANSYS andvirtual. Lab acoustics software simulation calculation, carries on the analysis from the aspects of simulation, the simulation results meet the design requirements. Therefore, the study of shows that the method is feasible and effective.