锁固型滑坡孕育过程低频声震效应及临滑前兆信息研究

The rock mass of locking segment in rockslides play a critical role in the overall stability of slope, so the study on low frequency seismoacoustic signal generated by the rock mass in locking section during evolution process of landslide is significantly important for precisely monitoring and early warning on rockslides. This project applies multi-methods including high-precision observation techniques, lab experiment and site monitoring to analyze the characteristics and dynamic evolution law of low frequency seismoacoustic emission during the break process of rock mass in locking section. Firstly, the high performance multi-channel seismoacoustic synchronous recording system, as well as the precise observational technique to capture extremely weak low frequency seismoacoustic signal will be developed. Secondly, through the methodology of lab experiment, site monitoring and unsteady-state signal analysis, the seismoacoustic emission and the dynamic revolution law of rock mass in locking section in the process of rock cracking, propagation, coalescence and failure are figured out, and further lead to the establishment of seismoacoustic recognition theory and model. On this basis, the research concentrates on the seismoacoustic effect at the moment of coalescence of rock cracks in locking section from steady-state to unsteady-state. Moreover, the precursor information recognition method of rockslide with locked section is proposed. This applied research associated with actual project cases is carried out for further a novel the monitoring and early warning method and stability analysis of rockslide.

岩质滑坡中的锁固段岩体对整个滑坡的整体稳定性起关键控制作用，研究锁固段岩体损伤破坏过程产生的低频声震信号对岩质滑坡成功监测预警至关重要。本项目拟采用微弱信号高精度探测技术和非稳态信号分析方法、室内试验和现场观测相结合的研究手段，对锁固型滑坡孕育过程低频声震效应及临滑前兆信息开展系统深入地研究。首先，研发高性能多通道声震同步探测试验与监测系统，重点研究锁固段滑坡孕育过程极微弱低频声震信号的探测技术与识别方法；其次，结合室内试验和现场监测，通过信号分析查明锁固段裂纹起裂、扩展、贯通到破坏全过程的声震发射现象、信号特征及演化规律；在此基础之上，研究锁固段岩体裂纹稳态到非稳态扩展瞬间的声震效应及强相关特征参数突变规律，探讨临滑声震异常和前兆信息；开展研究成果的工程应用研究，凝练锁固型滑坡孕育过程低频声震效应科学规律，提出此类滑坡监测预警新技术、新方法。

针对突发性强、监测难度大、预警方法缺乏的锁固段型岩质滑坡（或崩塌）灾害，本项目开展了锁固型岩质崩滑灾害灾变过程的低频声波、震动信号特征及演变规律研究，突破了传统变形监测预警技术方法，通过室内模型试验、现场监测试验以及数值模拟相结合的方法，重点研究了其关键控制岩块体在受力损伤破裂过程中的低频声波和震动信号辐射现象、频谱特征、变化规律及临界突变现象等。首先，研发和建立了锁固型滑坡孕育过程微弱低频声震信号的高精度探测与特征分析技术方法体系；其次，揭示了锁固段裂纹起裂、扩展、贯通到失稳破坏全过程的低频声震现象、机制特征及演化规律；最后，查明了锁固段微破裂到非稳定扩展瞬间的低频声震现象及强相关特征参数突变规律，探索了基于临界慢化理论的锁固型滑坡临滑前兆信息及预警方法，为突发性强的锁固型岩质滑坡灾害监测预警提供一种新技术方法路径。