土体中岩石破坏次声波的三维多测点振速矢量直线汇聚声源定位方法  

Sound source location method with three-dimensional multi-point measurement and particle velocity-vector linear convergence approach for infrasound generated by rock failure in soil

作　　者：赵久彬 刘元雪 柏准 杨骏堂 何少其 ZHAO Jiubin;LIU Yuanxue;BAI Zhun;YANG Juntang;HE Shaoqi(Department of Military Installations,Army Logistics University of PLA,Chongqing 401311,China;Chongqing Key Laboratory of Geomechanics and Geoenvironment Protection,Chongqing 401311,China)

机构地区：[1]陆军勤务学院军事设施系,重庆401311 [2]岩土力学与地质环境保护重庆市重点实验室,重庆401311

出　　处：《振动与冲击》2021年第14期144-152,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(41877219);重庆市自然科学基金项目(cstc2019jcyj-msxmX0585);重庆市规划和自然资源局科技计划项目(KJ-2018016)。

摘　　要：滑坡泥石流等地质灾害发生前夕,灾害体内的岩石土块发生爆裂、摩擦和断裂等破坏会产生低频次声波信号向外传播。在次声波声场中,声压是标量场,质点运动振速为矢量场,可以利用振速矢量场提前准确预测出灾害发生地点的三维坐标位置。采用数值模拟计算土体中发生小当量炸药爆炸,通过信号频谱分析得到爆炸冲击波衰减为次声波的主要能量频率为2~8 Hz,模拟出土体中岩石破坏发出同范围次声信号现象。基于此提出一种三维多测点振速矢量直线汇聚次声声源定位方法,在地质灾害体范围内不同位置部署N个监测点传感器阵列收集质点振速矢量信号,待地质体内岩石破坏发出次声信号,计算经过测点且其法线为振速方向矢量的N条直线指向并汇聚于声源发生处位置,通过求两两直线间最短距离线段方程,获得N-1个中点坐标,最后求各中点坐标的质心,预测为即将发生地质灾害的源头位置处。通过仿真模拟实体土质滑坡模型和分层介质模型中发出次声信号,布置3个测点位于模型中不同位置收集次声信号,采用该方法准确获得灾害体内部三维声源位置。该方法为提升滑坡泥石流等预警技术水平提供了新的思路。On the eve of geological hazards such as landslide and debris flow,rock and soil mass in the hazard body will be damaged by explosion,friction and fracture,which will produce and spread out low-frequency infrasound signals.In an infrasound sound field,sound pressure is a scalar field and particle velocity is a vector field.The velocity vector field can be used to accurately predict the three-dimensional coordinate position of the disaster location in advance.In the paper,numerical simulations were used to calculate the explosion of small equivalent explosive in soil.It is found the main energy frequency of the infrasound wave evolved from the attenuated explosive shock wave is between 2 and 8 Hz by signal spectrum analysis.The phenomenon of infrasound signal in the same frequency range generated by rock failure in excavated soil was simulated.Based on this,a method of locating infrasound source with three-dimensional multi-point hetero-plane linear aggregation was proposed.The particle velocity vector signal was collected by N sensor arrays in the wave field.It is proved that the N straight lines which pass through the measured point and whose normal is in the velocity vector direction will direct and converg to the place where the sound source occurs.Then,calculating the distance between two straight lines,a shortest distance line segment equation was built to obtain N-1 midpoint coordinates.The centroid coordinates of each midpoint coordinates are just the source location which can be used to predict the occurrence of geological hazards.As an example,the sound source location procedure was practiced by simulating infrasound signals from some solid soil landslide models and different media models,and arranging three measuring points were arranged at different positions in the model to collect infrasound signals,and the method is proved to be able to locate the 3D sound source location inside the disaster body accurately.The method provides a new idea for improving the early warning technology of landslide and de

关 键 词：次声波 声源定位 质点振速 直线汇聚 

分 类 号：TU45[建筑科学—岩土工程]