CN-122017040-A - Method for monitoring and early warning bedding rock slope through collaborative sensing of microseism and acoustic emission

CN122017040ACN 122017040 ACN122017040 ACN 122017040ACN-122017040-A

Abstract

The invention discloses a method for monitoring and early warning a bedding rock slope through collaborative perception of microseism and acoustic emission, which relates to the technical field of slope monitoring and early warning, wherein microseism signals and acoustic emission signals in a microseism and acoustic emission sensing array are acquired in real time at preset sampling frequencies corresponding to different sensor types, preprocessing the acquired signals, and dividing the preprocessed signals into natural fracture events, construction disturbance events and environmental noise events based on a pre-trained noise recognition model. The invention can give out effective early warning several hours to days earlier than the traditional displacement monitoring by capturing precursor behaviors such as microcrack initiation, interlayer friction and sliding and the like, realizes full-scale damage monitoring from millimeter-level cracks to meter-level fracture surfaces through cooperation of microseismic and acoustic emission, and simultaneously can give out space migration criteria aiming at layer direction control, thereby improving the special recognition capability of bedding slopes.

Inventors

WU SHUANGSHUANG
ZHOU BOYU
YAN JIANHUA
HAO SHUAI
SU HAOYANG
He Ruibai

Assignees

河海大学

Dates

Publication Date: 20260512
Application Date: 20260415

Claims (9)

1.A method for monitoring and early warning a bedding rock slope through collaborative perception of microseism and acoustic emission is characterized by comprising the following steps: s1, acquiring engineering geological information of a target bedding rock slope, and dividing the target bedding rock slope into different monitoring functional areas according to the acquired engineering geological information, wherein the monitoring functional areas comprise a slope top stretch-break area, a bedding slide-stretch area in the slope and a slope toe locking compression-shear area; S2, according to the monitoring function areas obtained after the target bedding rock slope is divided, arranging microseismic sensors and acoustic emission sensors in different monitoring function areas based on a preset sensor arrangement principle, and constructing a microseismic and acoustic emission sensing array of the target bedding rock slope; S3, acquiring microseismic signals and acoustic emission signals in the microseismic and acoustic emission sensing arrays in real time at preset sampling frequencies corresponding to different sensor types, preprocessing the acquired signals, and dividing the preprocessed signals into natural fracture events, construction disturbance events and environmental noise events based on a pre-trained noise recognition model; S4, extracting acoustic emission characteristic parameters, microseismic characteristic parameters and event space migration characteristics corresponding to the screened natural fracture event, and constructing a multidimensional characteristic parameter combination corresponding to the natural fracture event; S5, identifying the internal state of the target bedding rock slope through the constructed bedding rock slope progressive damage stage identification model according to the multidimensional characteristic parameter combination corresponding to the obtained natural fracture event, and obtaining a progressive damage stage corresponding to the internal state of the target bedding rock slope; s6, dynamically adjusting the weight of a preset evaluation index based on a progressive damage stage corresponding to the internal state of the target bedding rock slope, and calculating a slope danger comprehensive index of the target bedding rock slope; And S7, outputting a grading early warning result according to the slope hazard comprehensive index calculation result of the target bedding rock slope and the progressive damage stage corresponding to the internal state of the current target bedding rock slope.
2. The method for monitoring and early warning a bedding rock slope through collaborative perception of microseismic and acoustic emission according to claim 1, wherein the engineering geological information of the target bedding rock slope in S1 comprises one or more of slope height, slope angle, slope trend, stratum inclination angle, stratum thickness, weak interlayer position and thickness, potential sliding surface position, slope top pulling crack distribution condition, toe unloading relaxation area range, groundwater level and seepage channel distribution; in the process of dividing different monitoring functional areas in the target bedding rock slope, the boundaries of the divided monitoring functional areas are judged based on the combination of geological structure and deformation monitoring, and the specific basis is as follows: the boundary of the slope top fracture zone is determined according to a trailing edge fracture development zone, a maximum tensile strain zone or a displacement gradient abrupt change zone; the boundary of the bedding sliding expansion area in the slope is determined according to the exposure range of the bedding structural surface and the deep displacement centralized belt or the interlayer dislocation active belt; the boundary of the toe lock compression shear zone is determined according to the front edge anti-slip section, the compression strain concentrated belt, the shear strain abrupt belt or the potential shear outlet range.
3. The method for monitoring and early warning of a bedding rock slope through collaborative sensing of microseism and acoustic emission according to claim 1, wherein the specific implementation mode of arranging microseism sensors and acoustic emission sensors in different monitoring function areas based on a preset sensor arrangement principle in the step S2 comprises the following steps: An acoustic emission sensor is arranged in the top fracture zone of the slope and is used for monitoring high-frequency tensile acoustic emission events around the fracture; arranging acoustic emission sensors in boreholes along the trend and trend direction of a weak interlayer or a potential slip zone in a bedding sliding expansion area in the slope to form an in-hole array for monitoring interlayer friction slip acoustic emission signals; Arranging a microseismic detector in the toe locking compression shear area for monitoring a shearing microseismic event; and arranging a plurality of microseismic sensors on the slope surface to form a microseismic monitoring network with three-dimensional positioning capability.
4. The method for monitoring and early warning a bedding rock slope through collaborative perception of microseism and acoustic emission according to claim 1, wherein the preprocessing mode of the acquired signals in the step S3 comprises bandpass filtering, threshold triggering and waveform interception; the specific way of pre-training the noise recognition model is as follows: Manually marking the historical monitoring signals by geotechnical engineering technicians, dividing the historical monitoring signals into different event categories, wherein the event categories comprise natural fracture events, construction disturbance events and environmental noise events, and constructing a training sample set according to the divided historical monitoring signals of different event categories; extracting waveform characteristics of the monitoring signals corresponding to each sample in the constructed training sample set, wherein the waveform characteristics comprise main frequency, duration time, rising time and waveform symmetry of the signals, screening the range of waveform characteristic extraction required by the monitoring signals corresponding to the samples by combining a construction log time window, and constructing a joint characteristic vector corresponding to each sample; And training a machine learning classification model by combining the artificial labeling information of each sample in the training sample set and the corresponding joint feature vector of the corresponding sample to obtain a noise recognition model for recognizing the preset three event categories.
5. The method for monitoring and early warning a bedding rock slope through collaborative sensing of microseism and acoustic emission according to claim 1, wherein acoustic emission characteristic parameters in the step S4 comprise ringing count, accumulated energy, amplitude, rise time, duration, average frequency and rise angle; the microseismic characteristic parameters comprise event number, accumulated energy, visual stress, b value, event positioning coordinates, main frequency and time-space clustering degree; the event space migration characteristics are obtained by calculating migration speed of the acoustic emission dense band and the microseismic event cloud center of gravity along the direction of the bedding face trend in unit time and the change rate of the spread range along the bedding structural face.
6. The method for monitoring and early warning of the bedding rock slope through collaborative perception of microseismic and acoustic emission according to claim 1 is characterized in that a progressive damage stage identification model in the step S5 is a Markov state model, the input of the progressive damage stage identification model is a multi-dimensional characteristic parameter combination corresponding to an obtained natural fracture event, the output is probability and corresponding early warning grades of a target bedding rock slope based on different progressive damage stages, and the progressive damage stage corresponding to the internal state of the target bedding rock slope comprises a basic stability stage, an initial damage initiation stage, an interlayer slip activation stage, a crack penetration extension stage and a temporary slip instability stage.
7. The method for monitoring and early warning a bedding rock slope through collaborative sensing of microseism and acoustic emission according to claim 1, wherein the preset evaluation indexes in the step S6 comprise an acoustic emission liveness index, a microseism energy release index, an event space migration index, a b-value anomaly index, a displacement acceleration index and a rainfall induction correction index; The calculation formula of the comprehensive side slope risk index of the target bedding rock side slope is as follows: ; Wherein, the For the acoustic emission liveness index, Is an index of the release of microseismic energy, For the event space migration index, For the value of b to be an abnormality index, In order to be an index of the displacement acceleration, Correcting an index for rainfall induction; 、、、、 And And the weights are respectively corresponding to different preset evaluation indexes.
8. The method for monitoring and early warning the bedding rock slope through collaborative awareness of microseismic and acoustic emission according to claim 1 is characterized in that when the weights of preset evaluation indexes are dynamically adjusted in step 6, progressive damage stages corresponding to the internal states of the target bedding rock slope are obtained, the weights of all preset evaluation indexes bound in the corresponding progressive damage stages are adjusted according to the progressive damage stages corresponding to the internal states of the target bedding rock slope, and the weights of the same preset evaluation index in different progressive damage stages are different.
9. The method for monitoring and early warning of the bedding rock slope through collaborative perception of microseismic and acoustic emission according to claim 1, wherein the grading early warning result in the step S7 is one of a plurality of preset early warning levels, each early warning level corresponds to a preset dangerous comprehensive index interval and one or more progressive destruction stages, different advice measures are bound to different early warning levels, the dangerous comprehensive index interval corresponding to the output grading early warning result comprises a slope dangerous comprehensive index calculation result of the target bedding rock slope, and the progressive destruction stage corresponding to the output grading early warning result comprises a progressive destruction stage corresponding to the internal state of the current target bedding rock slope.

Description

Method for monitoring and early warning bedding rock slope through collaborative sensing of microseism and acoustic emission Technical Field The invention relates to the technical field of slope monitoring and early warning, in particular to a method for monitoring and early warning a bedding rock slope through collaborative perception of microseism and acoustic emission. Background The bedding rock slope refers to a slope type with a rock stratum trend substantially consistent with a slope trend and a similar inclination angle. Because the rock stratum shape is highly coupled with the slope shape, the slope is extremely easy to generate plane sliding type instability along the layer or the interlayer weak interlayer, and is one of slope types with highest danger and greatest treatment difficulty in engineering construction. The destabilization damage of the bedding rock slope not only has typical progressive property, namely, the bedding rock slope undergoes multi-stage evolution processes such as crack initiation, interlayer dislocation, crack penetration, acceleration destabilization and the like, but also has obvious burstiness, namely, the bedding rock slope can be converted from a peristaltic state to rapid collapse in a short time under the triggering of external rainfall, excavation or seismic disturbance. The two characteristics coexist, so that monitoring and early warning of the bedding rock slope becomes a key point and a difficult point in the field of engineering geology and geotechnical engineering. In the aspect of the existing monitoring and early warning technology, the current widely applied method mainly comprises a first class and a surface displacement monitoring method. And monitoring the deformation of the surface and the interior of the slope by using a total station, a GNSS, an inclinometer and a displacement meter as representatives. The method is mature in technology and strong in engineering operability, but basically belongs to passive posterior monitoring, and can only generate an identifiable signal after macroscopic deformation of a slope reaches a certain level, so that precursor behaviors such as deep crack initiation, interlayer slip and the like are difficult to capture, and the early warning advance is seriously insufficient. And second, a single microseismic monitoring method. Elastic waves generated by internal fracture of the rock mass are used as monitoring objects, and the time-space distribution, the energy evolution and the seismic source mechanism of the micro-fracture event are recorded in real time, so that the damage state of the inside of the slope can be reflected. A great deal of researches show that the microseismic technology can be used for evaluating the stability of the high slope of the hydropower engineering, and a good effect is obtained. But the single microseismic system has insufficient sensitivity to near-field small-scale cracks (especially interlayer friction sliding in millimeter to centimeter level), and has limited capture capability to early interlayer shearing dislocation of a bedding side slope. Third, a single acoustic emission monitoring method. Acoustic emissions are extremely sensitive to microcrack initiation and near field damage, and are capable of identifying high frequency, low energy microcrack activity. But acoustic emission signals decay fast, the effective propagation range is smaller, a monitoring network covering the whole bedding rock slope is difficult to be independently constructed, and the false alarm rate is high under the field complex noise background. Fourth, multi-parameter comprehensive monitoring method. And the partial engineering adopts multiparameter comprehensive monitoring of displacement, rainfall, underground water and the like, and takes threshold overrun as an early warning triggering condition. However, the method is usually based on statistical experience criteria, lacks of physical essential reflection of a failure mechanism, often depends on priori experience in threshold setting, has insufficient generalization capability and is difficult to adapt to bedding slopes of different engineering geological conditions. Therefore, the existing method has great defects in response to monitoring and early warning of the bedding rock slope, and development of a multi-source collaborative monitoring and early warning method which can organically integrate microseismic monitoring and acoustic emission monitoring based on physical field information and is specially used for the whole process of progressive damage of the bedding rock slope is needed. Disclosure of Invention The invention aims to provide a method for monitoring and early warning a bedding rock slope through collaborative sensing of microseism and acoustic emission, so as to solve the problems in the background art. In order to solve the technical problems, the invention provides the following technical scheme that the method for monitoring and e