The Experts below are selected from a list of 4443 Experts worldwide ranked by ideXlab platform

Chun’an Tang - One of the best experts on this subject based on the ideXlab platform.

  • Microseismic Monitoring and stability analysis of the right bank slope at Dagangshan hydropower station after the initial impoundment
    International Journal of Rock Mechanics and Mining Sciences, 2018
    Co-Authors: Xingzong Liu, Chun’an Tang, Li Lianchong, Run Sun
    Abstract:

    Abstract The right bank slope of the Dagangshan hydropower station in China has suffered from reservoir water pressure and seepage effects since the initial impoundment process. This paper describes the Microseismic Monitoring system and impoundment process of the Dagangshan hydropower station. Microseismic activity was detected in the right bank slope after the initial impoundment by the Microseismic Monitoring system. The spatiotemporal characteristics of the Microseismic events and the piezometer Monitoring results are used to confirm the conductive seepage pathways, the porous rock mass and the water recharge source in the right bank slope. Based on the geological conditions of the porous rock mass identified by Microseismic and piezometer Monitoring, a simplified two-dimensional (2D) finite element model is developed. A 2D finite element analysis is then applied to explore the damage mechanisms of local regions of the right bank slope after the initial impoundment. In addition, the load/unload response ratio theory is used to predict the failure of the slope based on the seismic source information obtained by the Microseismic Monitoring system. According to the actual geological conditions of the right bank slope, a simplified 3D numerical model is developed for the stability analysis of the right bank slope after the initial impoundment. Based on the porous rock mass identified by the Microseismic Monitoring, the effective stress is considered in the stability analysis. The safety factor of the right bank slope including the effective stress is 1.645, which indicates that the slope was stable after the initial impoundment. The Microseismic Monitoring technique can record disturbances caused by seepage effects in deep rock masses after the initial impoundment process in real time.

  • Microseismic Monitoring and 3D finite element analysis of the Right Bank Slope, Dagangshan hydropower station, during reservoir impounding
    Rock Mechanics and Rock Engineering, 2017
    Co-Authors: Xingzong Liu, Chun’an Tang, Hongyuan Liu
    Abstract:

    The right bank slope of Dagangshan hydropower station in China has complex geological conditions and is subjected to high in situ stress. Notably, Microseismic activities in the right bank slope occurred during reservoir impounding. This paper describes the Microseismic Monitoring technology, and three-dimensional (3D) finite element analysis is used to explore the Microseismic activities and damage mechanisms in the right bank slope during reservoir impounding. Based on data obtained from Microseismic Monitoring, a progressive Microseismic damage model is proposed and implemented for 3D finite element analysis. The safety factor for the right bank slope after reservoir impoundment obtained from the 3D finite element analysis, which included the effects of progressive Microseismic damage, was 1.10, indicating that the slope is stable. The Microseismic Monitoring system is able to capture the slope disturbance during reservoir impounding in real time and is a powerful tool for qualitatively assessing changes in slope stability over time. The proposed progressive Microseismic damage model adequately simulates the changes in the slope during the impoundment process and provides a valuable tool for evaluating slope stability.

  • Study on Rockburst Nucleation Process of Deep-Buried Tunnels Based on Microseismic Monitoring
    Shock and Vibration, 2015
    Co-Authors: Chun’an Tang, Guanwen Cheng, Lie-xian Tang
    Abstract:

    The objective of this study was to investigate the rockburst nucleation process and provide a theoretical basis for its prediction. A Microseismic Monitoring system was established in deep tunnels at Jinping II Hydropower Station. Using a digital multichannel Microseismic Monitoring system and Monitoring technique, twenty-four-hour continuous real-time Monitoring of macroscopic was realized in diversion tunnel #3. Substantial Microseismic Monitoring data were acquired to study the macroeconomic instability failure mechanisms in the rockburst nucleation process in terms of dynamic crack propagation, including microcrack initiation, development, propagation, shear zone formation, and coalescence. The intrinsic relationship between the spatiotemporal evolution patterns of the Microseismicity and the rockbursts was preliminarily explored. The Monitoring and analysis results indicated that the driving source of certain rockbursts could be expressed as the combined results of the local rockburst energy and the transfer energy; that is, . Strong rockbursts can induce the recurrence of rockbursts in nearby locations. In addition, a comparative analysis of the formation and failure mode of molds in underground caverns was performed using the finite element analysis program RFPA. Based on this engineering study, we verified the feasibility of applying Microseismic Monitoring to rockbursts in deep rock tunnels.

  • Microseismic Monitoring and numerical simulation on the stability of high-steep rock slopes in hydropower engineering
    Journal of Rock Mechanics and Geotechnical Engineering, 2015
    Co-Authors: Chun’an Tang
    Abstract:

    Abstract For high-steep slopes in hydropower engineering, damage can be induced or accumulated due to a series of human or natural activities, including excavation, dam construction, earthquake, rainstorm, rapid rise or drop of water level in the service lifetime of slopes. According to the concept that the progressive damage (Microseismicity) of rock slope is the essence of the precursor of slope instability, a Microseismic Monitoring system for high-steep rock slopes is established. Positioning accuracy of the Monitoring system is tested by fixed-position blasting method. Based on waveform and cluster analyses of Microseismic events recorded during test, the tempo-spatial distribution of Microseismic events is analyzed. The deformation zone in the deep rock masses induced by the Microseismic events is preliminarily delimited. Based on the physical information measured by in situ Microseismic Monitoring, an evaluation method for the dynamic stability of rock slopes is proposed and preliminarily implemented by combining Microseismic Monitoring and numerical modeling. Based on the rock mass damage model obtained by back analysis of Microseismic information, the rock mass elements within the Microseismic damage zone are automatically searched by finite element program. Then the stiffness and strength reductions are performed on these damaged elements accordingly. Attempts are made to establish the correlation between Microseismic event, strength deterioration and slope dynamic instability, so as to quantitatively evaluate the dynamic stability of slope. The case studies about two practical slopes indicate that the proposed method can reflect the factor of safety of rock slope more objectively. Numerical analysis can help to understand the characteristics and modes of the monitored Microseismic events in rock slopes. Microseismic Monitoring data and simulation results can be used to mutually modify the sensitive rock parameters and calibrate the model. Combination of Microseismic Monitoring and numerical simulation provides a more objective basis for the numerical model and parameters and a solid mechanical foundation for the Microseismic Monitoring.

  • Microseismic Monitoring and Numerical Simulation of Rock Slope Failure
    International Journal of Distributed Sensor Networks, 2013
    Co-Authors: Zhengzhao Liang, Shibin Tang, Chun’an Tang
    Abstract:

    A numerical code with an elastic-brittle failure model has been developed to simulate the seismic activities in rock failure problems. The feasibility in principle of Monitoring and prediction of rock failure was numerically simulated. The heterogeneity was considered to be the main reason for the existence of slope failure precursors. Seismic events could be observed in heterogeneous rock, whereas the homogeneous rocks showed an abrupt fracture mode without any early seismic precursors. The failure process of a slope was numerically investigated by using a gravity increase method (centrifugal loading method), and the application of the Microseismic Monitoring system in the slope was introduced. The numerical results showed that the fracture of the main faults caused the slope slide, and the microcracking caused by the heterogeneity in the faults prior to the landslide could be considered as the precursors of the slope failure, which were captured by the Microseismic Monitoring system. The Microseismic Monitoring technique was proved to be successful in predicting the failure in the slope, and the numerical results will be helpful in interpreting the Microseismic Monitoring results.

Chun An Tang - One of the best experts on this subject based on the ideXlab platform.

  • Microseismic Monitoring positioning principle and sensor layout strategy of rock mass engineering
    Geofluids, 2020
    Co-Authors: Daoyuan Lin, Chun An Tang, Kedar Prasad Yadav, Zhiqiang Feng
    Abstract:

    Microseismic Monitoring technology can start from the most initial stage of rock deformation and track and monitor the progressive failure process of rock mass from the fracture of rock blocks to the instability of rock mass. Thus, the scientific nature of Monitoring work is greatly promoted, and the accuracy and advance of the prediction of engineering and geological disasters are improved. In this paper, the fracture and instability of rock can be analyzed by analyzing the Microseismic signals produced by rock failure; The location of Microseismic source can be determined by multipoint synchronous data acquisition to determine the time when each sensor (at least 5) receives Microseismic signals; Combined with practical engineering experience for underground engineering in growth, heading tunnel, put forward only sensor arrangement to take mobile, follow the semienclosed layout network. We hope to give some reference to the researchers who are concerned with Microseismic Monitoring technology.

  • Research on the Law of Large-Scale Deformation and Failure of Soft Rock Based on Microseismic Monitoring
    Advances in Civil Engineering, 2018
    Co-Authors: Feng Chen, Chun An Tang, Fei Liu
    Abstract:

    Based on the existing Canadian ESG Microseismic Monitoring system, a mobile Microseismic Monitoring system for a soft rock tunnel has been successfully constructed through continuous exploration and improvement to study the large-scale nucleation and development of microfractures in the soft rock of the Yangshan Tunnel. All-weather, continuous real-time Monitoring is conducted while the tunnel is excavated through drilling and blasting, and the waveform characteristics of Microseismic events are analysed. Through the recorded Microseismic Monitoring data, the variation characteristics of various parameters (e.g., the temporal, spatial, and magnitude distributions of the Microseismic events, the frequency of Microseismic events, and the Microseismic event density and energy) are separately studied during the process of large-scale deformation instability and failure of the soft rock tunnel. The relationship between the deterioration of the rock mass and the Microseismic activity during this failure process is consequently discussed. The research results show that a Microseismic Monitoring system can be used to detect precursors; namely, the Microseismic event frequency and energy both will appear “lull” and “active” periods during the whole failure process of soft rock tunnel. Two peaks are observed during the evolution of failure. When the second peak occurs, it is accompanied by the destruction of the surrounding rock. The extent and strength of the damage within the surrounding rock can be delineated by the spatial, temporal, and magnitude distributions of the Microseismic events and a Microseismic event density nephogram. The results of Microseismic analysis confirm that a Microseismic Monitoring system can be used to monitor the large-scale deformation and failure processes of a soft rock tunnel and provide early warning for on-site construction workers to ensure the smooth development of the project.

  • a zoning model for coal mining induced strata movement based on Microseismic Monitoring
    International Journal of Rock Mechanics and Mining Sciences, 2017
    Co-Authors: Guanwen Cheng, Hongyuan Liu, Chun An Tang, Sujian Wang
    Abstract:

    A Microseismic Monitoring technique is adopted to investigate the distribution regularity of Microseismic events released by the coal mining - induced roof rock mass along the vertical and horizontal directions in combination with mine geological data. On the basis of the quantity and energy distributions of the Microseismic events recorded using the Microseismic Monitoring technique, a zoning method is first established for the roof strata movement in the vertical and horizontal directions. The vertically zoning method is then applied to analyze the Microseismic Monitoring results obtained in the Dongjiahe Coal Mine, which divides rock mass into six zones along the vertical direction, i.e. the caved zone, the block zone, the vertical fracture through-going zone, the vertical fracture zone, the separation zone and the continuous zone. The horizontally zoning model divides the roof strata movement into three zones, i.e. the calm zone, the generation zone impacted by working face and the historical generation zone. After that, based on the horizontally zoning model, a method is developed to determine the displacement angle using the Microseismic Monitoring data, which has been verified in the Dongjiahe Coal Mine.

  • Microseismic Monitoring System Establishment and its Application to Xinzhangzi Coal Mine
    Advanced Materials Research, 2011
    Co-Authors: Dong Duan, Chun An Tang, Xiao Jing Feng
    Abstract:

    Microseismic Monitoring technology is the important method for safety Monitoring of coal mine. The Xinzhuangzi coal mine is high gas and outburst mine, in order to ensure safety in process of mining and tunneling, the Microseismic Monitoring system is built. Waveform analysis database of Microseismic information and interference signal is built, the results of Microseismic Monitoring is preliminary analyzed. The results showed that Microseismic Monitoring system is stable and reliable, and the results are accurate. Microseismic Monitoring technology provides a new Monitoring tool and method for coal mining.

Guangliang Feng - One of the best experts on this subject based on the ideXlab platform.

  • Microseismic Monitoring Method of the Rockburst Evolution Process
    Rockburst, 2018
    Co-Authors: Yaxun Xiao, Xiating Feng, Bingrui Chen, Guangliang Feng
    Abstract:

    Abstract This chapter describes the Microseismic Monitoring method of the rockburst evolution process in tunnels or large caverns in the fields of civil, hydraulic, or mining engineering. Several key points (e.g., equipment selection, measures for improving Monitoring quality, data analysis, and results presentation) are illustrated in detail by a typical intense rockburst case in the Jinping II tunnels.

  • isrm suggested method for in situ Microseismic Monitoring of the fracturing process in rock masses
    Rock Mechanics and Rock Engineering, 2016
    Co-Authors: Yaxun Xiao, Xiating Feng, Bingrui Chen, J A Hudson, Guangliang Feng
    Abstract:

    The purpose of this ISRM Suggested Method is to describe a methodology for in situ Microseismic Monitoring of the rock mass fracturing processes occurring as a result of excavations for rock slopes, tunnels, or large caverns in the fields of civil, hydraulic, or mining engineering. In this Suggested Method, the equipment that is required for a Microseismic Monitoring system is described; the procedures are outlined and illustrated, together with the methods for data acquisition and processing for improving the Monitoring results. There is an explanation of the methods for presenting and interpreting the results, and recommendations are supported by several examples.

T. Jbeili - One of the best experts on this subject based on the ideXlab platform.

Hongyuan Liu - One of the best experts on this subject based on the ideXlab platform.

  • a zoning model for coal mining induced strata movement based on Microseismic Monitoring
    International Journal of Rock Mechanics and Mining Sciences, 2017
    Co-Authors: Guanwen Cheng, Hongyuan Liu, Chun An Tang, Sujian Wang
    Abstract:

    A Microseismic Monitoring technique is adopted to investigate the distribution regularity of Microseismic events released by the coal mining - induced roof rock mass along the vertical and horizontal directions in combination with mine geological data. On the basis of the quantity and energy distributions of the Microseismic events recorded using the Microseismic Monitoring technique, a zoning method is first established for the roof strata movement in the vertical and horizontal directions. The vertically zoning method is then applied to analyze the Microseismic Monitoring results obtained in the Dongjiahe Coal Mine, which divides rock mass into six zones along the vertical direction, i.e. the caved zone, the block zone, the vertical fracture through-going zone, the vertical fracture zone, the separation zone and the continuous zone. The horizontally zoning model divides the roof strata movement into three zones, i.e. the calm zone, the generation zone impacted by working face and the historical generation zone. After that, based on the horizontally zoning model, a method is developed to determine the displacement angle using the Microseismic Monitoring data, which has been verified in the Dongjiahe Coal Mine.

  • Microseismic Monitoring and 3D finite element analysis of the Right Bank Slope, Dagangshan hydropower station, during reservoir impounding
    Rock Mechanics and Rock Engineering, 2017
    Co-Authors: Xingzong Liu, Chun’an Tang, Hongyuan Liu
    Abstract:

    The right bank slope of Dagangshan hydropower station in China has complex geological conditions and is subjected to high in situ stress. Notably, Microseismic activities in the right bank slope occurred during reservoir impounding. This paper describes the Microseismic Monitoring technology, and three-dimensional (3D) finite element analysis is used to explore the Microseismic activities and damage mechanisms in the right bank slope during reservoir impounding. Based on data obtained from Microseismic Monitoring, a progressive Microseismic damage model is proposed and implemented for 3D finite element analysis. The safety factor for the right bank slope after reservoir impoundment obtained from the 3D finite element analysis, which included the effects of progressive Microseismic damage, was 1.10, indicating that the slope is stable. The Microseismic Monitoring system is able to capture the slope disturbance during reservoir impounding in real time and is a powerful tool for qualitatively assessing changes in slope stability over time. The proposed progressive Microseismic damage model adequately simulates the changes in the slope during the impoundment process and provides a valuable tool for evaluating slope stability.