岩土力学2017，Vol.38Issue(7)：2149-2156,8.DOI:10.16285/j.rsm.2017.07.039
基于固有振动频率的滑移式和坠落式危岩块体稳定性评价模型研究
A model for evaluation of stability of sliding-and falling-type dangerous rock blocks based on natural vibration frequency
摘要
Abstract
Since the instability of dangerous rock mass exhibits as the sudden collapse of destruction,no obvious displacement characteristics can be identified.Thus,the application of conventional displacement monitoring techniques is difficult to achieve the purpose of monitoring and early warning.In addition,the stability of dangerous rock mass is influenced by the bonded area between dangerous rock block and bedrock,which is considered as one of the critical parameters.However,this bonded area is hard to obtain,which makes it difficult to evaluate the stability of the dangerous rock block.In this study,we assume that the rock block is homogeneous and isotropic,the main control structural plane is a single plane,the damping ratio of the system is less than 1 and the deformation is linear elastic deformation within the amplitude range.As a result,the vibration model of the dangerous rock mass can be simplified as a spring oscillator model.Then,the relationships among the natural vibration frequency of dangerous rock mass,the bonding area,the elastic modulus and the quality of dangerous rock mass were established by the theoretical derivation.Considering the limit equilibrium model,a new model based on natural vibration frequency was derived to evaluate the stability of dangerous rock mass.A dangerous rock block on the right bank of Baihebao reservoir was selected as the case study.A wireless vibration sensor (micro core) was fixed on the dangerous rock block to acquire data,which was converted to natural vibration frequency by the Fourier transform and other mathematical methods.Furthermore,the bonded area was determined according to the relationship among natural vibration frequency,rock block bonding area and elastic modulus.Finally,the stability evaluation of dangerous rock mass was completed using the new model.This case study verifies the feasibility of the proposed procedure with a faster rate and more accuracy than traditional methods.关键词
危岩块体/固有振动频率/傅里叶变换/稳定性评价Key words
dangerous rock block/natural vibration frequency/Fourier transform/stability evaluation分类
数理科学引用本文复制引用
贾艳昌,谢谟文,昌圣翔,吕夫侠..基于固有振动频率的滑移式和坠落式危岩块体稳定性评价模型研究[J].岩土力学,2017,38(7):2149-2156,8.基金项目
国家自然科学基金资助项目:基于动力特征参数的边坡危岩块体稳定性监测评价模型研究(No.41572274).This work was supported by the National Natural Science Foundation of China:Study on Monitoring and Evaluation Model of Slope Dangerous Rock Mass Stability Based on Dynamic Characteristic Parameters (41572274). （No.41572274）
