岩石（体）变形破坏过程中的次声波特性研究

Currently, the research of rock failure text must be conducted by putting sensors on or near to the specimens,and the monitoring equipments of rock failur which rely on it can only realize fixed-point monitoring and it performs inability in distant area monitoring. Researchers of this project attempt to use the features of infrasonic waves such as longer propagation distance and slower energy declining to seek the relationship between rock failure and infrasonic,and to study the possibility of distance monitoring of rock failure.The mainly work of this project is as follows:(1)The infrasonic of rock failure is tested and analyzed by destruction experiments of different lighology and different saturation state under the conditon of different forced state;(2) The difference of infrasonic in fiel and indoor experiment by conducting field in-situ tests and comparing the results of field test and indoor experiment;(3) Comprehensive Analysis of all the results and try to epurate the infrasonic characteristics during the course of rock body failure and find the precursor information of infrasonic of rock failure.From the research above ,we want to provide some evidence for realizing area monitoring for geological disaster such landslide and collapse.

当前对于岩体变形破坏的试验研究需要将传感器布置在试件上或距离很近的位置，由此发展起来的各种岩体变形破坏的监测设备也只能实现定点监测，而对于较远距离的区域性监测则无能为力。本研究试图利用次声波传播距离远、能量衰减慢的特点，探寻岩体破裂与次声波的关系，并探讨利用次声波实现较远距离监测岩体破坏的可能性。项目具体在以下几个方面开展工作：（1）通过不同岩性、不同含水状态的岩石试件在不同的受力状态下破坏的次声波测试，分析次声波特性；（2）通过现场试验过程中的次声波测试，分析室内小尺寸试件与现场原位试验所产生的次声波的差异；（3）综合分析以上结果，提炼岩石（体）破坏过程中的次声波特征，找出岩体破坏前兆次声波信息。通过以上研究，以期能够为实现滑坡、崩塌等地质灾害的远程区域监测提供依据。

以往对岩体变形破坏的监测，主要通过埋置与岩体内部的传感器捕捉岩体结构变形特征，从而实现预警的目的。这是一种点状的监测方法，无法满足当前地质灾害面状监测及防控的需求。项目利用次声波传播距离远、能量衰减慢的特点，探讨利用次声波实现较远距离监测岩体破坏及预警的可能性。项目通过大量的室内外试验，采集了大量的岩体破坏次声信息，并进行了细致分析，取得如下成果：明确了岩石破坏次声信号的卓越频率范围及能量分布，为实际应用中岩体破坏次声信号的识别提供了依据；通过岩体不同破坏阶段能量时频特性变化的分析，初步建立了岩体破坏前兆预警的基础指标，为岩体破坏预警模型的建立提供了理论基础；通过对不同受力状态下次声信号波形、功率谱及频率特征的分析，明确了不同受力状态下岩体破坏次声信号的差异。上述研究成果的取得，进一步证明了利用次声信息进行大型岩体破坏预测预警的可行性，并初步在信号识别及预警指标两大关键性技术问题上取得一定的进展，为推动次声监测技术在地质灾害领域更深入的研究和后续的推广应用提供了必要的理论基础及实践经验。