大型多功能高压岩石结构面剪切伺服试验系统及功能测试分析

High pressure shearing servo testing system for rock joint with multi modes and corresponding function test analysis

高法向应力和常法向刚度边界是深部岩体结构面基本边界约束特征,开发具有高法向荷载、大剪切面积、多剪切模式、长剪切距离的岩石结构面剪切伺服试验系统是认识深部岩体结构面剪切变形与破坏的前提。为此,阐述了新开发的大型多功能高压岩石结构面剪切伺服试验系统的特征参数和功能特性。该系统由法向与剪切加卸载子系统、伺服控制子系统、数据采集与交互软件子系统、液压油源辅助子系统等组成,其最大法向荷载为1500 kN、最大剪切荷载为2000 kN,可适用尺寸为20 cm×10 cm×20 cm、30 cm×20 cm×30 cm和50 cm×30 cm×30 cm(长×宽×高)的结构面剪切/试块剪断试验。试验过程可采用复杂的法向加卸载(NLU)、常法向荷载(CNL)、常法向刚度(CNS)、快/慢剪(FLS)、往返剪(GBS)等试验模式,辅助有剪切观测视窗和声发射定位监测。基于水泥材质结构面和岩石试样开展本系统的功能测试试验结果表明,由于采用了先进的硬件结构设计和高效的伺服软件控制,该高压伺服试验系统可以实现高频伺服反馈控制和数据自动采集,从而可获得稳定和可靠的结构面试样剪切测试结果,支撑深部含结构面岩体稳定性理论研究和工程应用分析。

The high normal stress and constant normal stiffness are the general boundary constraint features of deep rock joints.Advanced rock joint shear servo test system with high normal load,large shear area,multi-shear mode and long shear distance is the premise for understanding the shearing deformation and failure of rock joints in deep stress condition.Thus,a new shear servo testing system,with large-scale,multi-functional and high-pressure,is invented.The system consists of normal and shear loading and unloading subsystems,servo control subsystems,data acquisition and software subsystems,and hydraulic oil source auxiliary subsystems.The functional parameters of the testing system include the maximum normal load of 1500 kN,the maximum shear load of 2000 kN.This testing system is available for the rock joint shearing test on the sample with standard sizes of 20 cm×10 cm×20 cm,30 cm×20 cm×30 cm and 50 cm×30 cm×30 cm(length×width×height).The testing system can finish complex loading and unloading,constant normal loading(CNL),constant normal stiffness(CNS),fast/slow shearing,reciprocating shearing and other loading modes,assisting with shear observation window and acoustic emission positioning monitoring.Based on the test specimens of cement material and rock specimens,the experimental results show that this servo testing system can achieve high-frequency feedback control and data acquisition due to the excellent hardware structure and efficient software control,which can give out stable and reliable experimental data,support the stability study and engineering application analysis for deep rock engineering.