In light of the complex and dynamic mechanical properties of evolving weak strata in open-pit mines,and the consequent difficulty of determining their mechanical parameters,this study uses the ultimate balance theory,...In light of the complex and dynamic mechanical properties of evolving weak strata in open-pit mines,and the consequent difficulty of determining their mechanical parameters,this study uses the ultimate balance theory,along with the back analysis method combined with monitoring data on field displacement,to carry out parameter inversion using the FLAC3D numerical simulation software.The edge slope of a working pit of the Weijiamao open-pit mine was used as research object to this end.As the results obtained by the constitutive model were consistent with the field monitoring data,the evolving weak strata in the slope and the position of the landslide in the mine could be obtained.The landslide was directed northeast.The mechanism of the edge slope of the working pit was identified as unloading shear failure,and the feasibility of the method of parameter inversion was verified.The internal friction angle φand cohesion C of evolving weak strata in the slope of the open-pit mine were also obtained,where this compensated for the deficiency of laboratory tests and enabled the transformation from qualitative to quantitative analysis.This can provide a reliable basis for the safe operation of open-pit mines.展开更多
A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding ...A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding slopes.The present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s influence.The assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is identified.Furthermore,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical use.During the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial one.Overall,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.展开更多
Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challe...Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challenging when training data(e.g.truck haulage information and weather conditions)are massive.In machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden layers.This study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training data.Before the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input variables.To verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark models.The DNN model with multiple hidden layers performed better than the ANN models with a single hidden layer.The DNN model outperformed the extensively applied benchmark models in predicting ore production.This can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.展开更多
In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production...In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production,the separate transportation mode of underpass bridge and overpass steel trestle is proposed to optimize the open pit development transportation system,so as to solve the practical problems that the horizontal cross of transport vehicles causes vehicle blockage,affects production schedule and production safety.The results show that the horizontal crossing road can be changed into a separate type of overpass steel trestle,which can realize the classified transportation of large and small vehicles,reduce the traffic density,make vehicles with different functions go their own way,eliminate the hidden danger of traffic accidents,and improve the production efficiency.展开更多
Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining tech...Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.展开更多
The design and practice in supporting the cut slope of an open-pit mine wereintroduced, in which the high pressure grouting method was used in reinforcing the weak formation inthe slopes. Based on a detailed geologica...The design and practice in supporting the cut slope of an open-pit mine wereintroduced, in which the high pressure grouting method was used in reinforcing the weak formation inthe slopes. Based on a detailed geological survey of the slope, a theoretical analysis was carriedout, and the design parameters were proposed, where the Tresca or Mohr-Coulomb yield criteria wasemployed. A patent technology, named 'Technology of high pressure and multiple grouting in differentlevels within a single hole', was employed in the construction. Anchor bars were also installed asgrouting proceeds. This method combines anchoring and grouting comprehensively and was foundsuccessful in practice.展开更多
Displacement monitoring in open-pit mines is one of the important tasks for safe management of mining processes.Differential interferometric synthetic aperture radar(DInSAR),mounted on an artificial satellite,has the ...Displacement monitoring in open-pit mines is one of the important tasks for safe management of mining processes.Differential interferometric synthetic aperture radar(DInSAR),mounted on an artificial satellite,has the potential to be a cost-effective method for monitoring surface displacements over extensive areas,such as open-pit mines.DInSAR requires the ground surface elevation data in the process of its analysis as a digital elevation model(DEM).However,since the topography of the ground surface in open-pit mines changes largely due to excavations,measurement errors can occur due to insufficient information on the elevation of mining areas.In this paper,effect of different elevation models on the accuracy of the displacement monitoring results by DInSAR is investigated at a limestone quarry.In addition,validity of the DInSAR results using an appropriate DEM is examined by comparing them with the results obtained by global positioning system(GPS)monitoring conducted for three years at the same limestone quarry.It is found that the uncertainty of DEMs induces large errors in the displacement monitoring results if the baseline length of the satellites between the master and the slave data is longer than a few hundred meters.Comparing the monitoring results of DInSAR and GPS,the root mean square error(RMSE)of the discrepancy between the two sets of results is less than 10 mm if an appropriate DEM,considering the excavation processes,is used.It is proven that DInSAR can be applied for monitoring the displacements of mine slopes with centimeter-level accuracy.展开更多
To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of th...To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of the 34,600 profile are obtained on the basis of hydrology, geology, and monitoring data.The residual thrust method is utilized to calculate the stability coefficients, which are 1.225 and 1.00 under sound and transfixion conditions, respectively. According to the rock damage and fragmentation and the principle of mechanical parameter degradation, the mechanical models of the slide mass development of the hard and soft rock slopes are established. An integrated model for calculating the slope stability coefficient is built considering water, vibration, and other external factors that pertain to the structural plane damage mechanism and the generating mechanism of the sliding mass. The change curve of the stability coefficient in the slide mass development is obtained from the relevant analyses,and afterwards, the stability control measures are proposed. The analysis results indicate that in the cracking stage of the hard rock, the slope stability coefficient decreases linearly with the increase in the length Lbof the hard rock crack zone. The linear slope is positively correlated to rock cohesion c. In the transfixion stage of the soft rock, the decrease speed of the stability coefficient is positively correlated to the residual strength of the soft rock. When the slope is stable, the stability coefficient is in a quadratic-linear relationship with the decreased height Dh of the side slope and in a linear relationship with anchoring force P.展开更多
Under circumstances in which both underground mining and open-pit mining are employed, the mining effects of two approaches will be superposed and the mining slope will receive several induced stress fields, which mak...Under circumstances in which both underground mining and open-pit mining are employed, the mining effects of two approaches will be superposed and the mining slope will receive several induced stress fields, which makes the sliding mechanism and deformation law of slope rock mass more complicated. This paper, targeting at the east slope of Antaibao Mine with the joint employment of underground mining and open-pit mining, aims to study the moving law of the slope rock mass and the damage mechanism to the overburden of the goaf by numerical simulation. It is supposed that models of possible damage to the slope could be explored for guidance to safety-production of the mine.展开更多
Two critical factors,namely intense precipitation and intricate excavation,can trigger rock mass disasters in mining operations.In this study,an indoor rainfall system was developed to precisely regulate the flow and ...Two critical factors,namely intense precipitation and intricate excavation,can trigger rock mass disasters in mining operations.In this study,an indoor rainfall system was developed to precisely regulate the flow and intensity of precipitation.A large-scale model experiment was conducted on a self-designed physical simulation experiment platform to investigate the failure and instability of high-steep rock slopes under unsaturated conditions.The real-time reproduction of the progressive failure process in high-steep rock slopes enabled the determination of the critical rainfall intensity and revealed the mechanism underlying slope instability.Experiment results indicated that rainfall may be the primary factor contributing to rock mass instability,while continuous pillar mining exacerbates the extent of rock mass failure.The critical failure stage of high-steep rock slopes occurs at a rainfall intensity of 40 mm/h,whereas a rainfall exceeding 50 mm can induce critical instability and precipitation reaching up to 60 mm will result in slope failure.The improved region growing segmentation method(IRGSM)was subsequently employed for image recognition of rock mass deformation in underground mines.Herein an error comparison with the simple linear iterative cluster(SLIC)superpixel method and the original region growing segmentation method(ORGSM)showed that the average identification error in the X and Y directions by the method was reduced significantly(1.82%and 1.80%in IRGSM;4.70%and 6.26%in SLIC;9.45%and 12.40%in ORGSM).Ultimately,the relationship between rainfall intensity and failure probability was analyzed using the Monte Carlo method.Moreover,the stability assessment criteria of rock slope under unsaturated condition were quantitatively and accurately evaluated.展开更多
The significant difference between the mechanical properties of soft rock and hard rock results in the complexity of the failure mode of the anti-dip layered slope with soft and hard rock interbedding.In order to reve...The significant difference between the mechanical properties of soft rock and hard rock results in the complexity of the failure mode of the anti-dip layered slope with soft and hard rock interbedding.In order to reveal the landslide mechanism,taking the north slope of Fushun West Open-pit Mine as an example,this paper analyzed the failure mechanism of different landslides with monitoring and field surveys,and simulated the evolution of landslides.The study indicated that when the green mudstone(hard rock)of the anti-dip slope contains siltized intercalations(soft rock),the existence of weak layers not only aggravates the toppling deformation of anti-dip layered slope with high dip,but also causes the shear failure of anti-dip layered slope with stable low dip.The shear failure including subsidence induced sliding and wedge failure mainly exists in the unloading zone of the slope.Its failure depth and failure time were far less than that of toppling failure.In terms of the development characteristics of deformation,toppling deformation has the long-term and progressive characteristics,but shear failure deformation has the abrupt and transient characteristics.This study has deepened the understanding of such slope landslide mechanism,and can provide reference for similar engineering.展开更多
Estimation of stability of natural slopes, embankments, dams and open-pit slopes during earthquakes are complex and non-linear problems, therefore physical modeling is used for decision of it. As a result of physical ...Estimation of stability of natural slopes, embankments, dams and open-pit slopes during earthquakes are complex and non-linear problems, therefore physical modeling is used for decision of it. As a result of physical modeling the pattern of seismic vibrations impact based on the movement process of probable collapse prism delineated by the most stressed plane of sliding has been established. Particular recommendations on the basis of safety factors selection in seismoactive zones are given.展开更多
Due to the loose structure,high porosity and high permeability of soil-rock mixture slope,the slope is unstable and may cause huge economic losses and casualties.The h-type anti-slide pile is regarded as an effective ...Due to the loose structure,high porosity and high permeability of soil-rock mixture slope,the slope is unstable and may cause huge economic losses and casualties.The h-type anti-slide pile is regarded as an effective means to prevent the instability of soilrock mixture slope.In this paper,a centrifuge model test was conducted to investigate the stress distribution of the h-type anti-slide pile and the evolution process of soil arching during the loading.A numerical simulation model was built based on the similar relationship between the centrifuge model and the prototype to investigate the influence factors of the pile spacing,anchored depth,and crossbeam stiffness,and some recommendations were proposed for its application.The results show that the bending moment distribution of the rear pile exhibits Wshaped,while for the front pile,its distribution resembles V-shaped.The soil arching evolution process during loading is gradually dissipated from bottom to top and from far to near.During the loading,the change of bending moment can be divided into three stages,namely,the stabilization stage,the slow growth stage,and the rapid growth stage.In engineering projects,the recommended values of the pile spacing,anchored depth,and crossbeam stiffness are 4.0d,2.0d,and 2.0EI,where d and EI are the diameter and bending stiffness of the h-type anti-slide pile respectively.展开更多
In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detecti...In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detection by existing conventional monitoring methods, this paper establishes an open-pit mine monitoring data set, and proposes a real-time intelligent monitoring model based on UAV. The reasoning component with strong computing power and low power consumption is selected, and the lightweight object detection model is selected for the experiment. A quantitative standard of dynamic energy consumption detection by evaluation algorithm is proposed. Through experimental comparison, it is found that YOLOv4-tiny has the highest comprehensive grade in detection accuracy, speed, energy consumption and other aspects, which is suitable for application in the above model.展开更多
基金the State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Beijing(No.SKLGDUEK1923)Special fund for basic scientific research of central universities(Grant no:2013QZ04).
文摘In light of the complex and dynamic mechanical properties of evolving weak strata in open-pit mines,and the consequent difficulty of determining their mechanical parameters,this study uses the ultimate balance theory,along with the back analysis method combined with monitoring data on field displacement,to carry out parameter inversion using the FLAC3D numerical simulation software.The edge slope of a working pit of the Weijiamao open-pit mine was used as research object to this end.As the results obtained by the constitutive model were consistent with the field monitoring data,the evolving weak strata in the slope and the position of the landslide in the mine could be obtained.The landslide was directed northeast.The mechanism of the edge slope of the working pit was identified as unloading shear failure,and the feasibility of the method of parameter inversion was verified.The internal friction angle φand cohesion C of evolving weak strata in the slope of the open-pit mine were also obtained,where this compensated for the deficiency of laboratory tests and enabled the transformation from qualitative to quantitative analysis.This can provide a reliable basis for the safe operation of open-pit mines.
基金This work has received funding from the European Union’s Research Fund for Coal and Steel under the projects RAFF grant agreement No.847299 and POMHAZ grant agreement No.101057326.Financial assistance by the European Commission is much appreciated.
文摘A common reclamation practice for closed coal surface mines is filling them with water to form pit lakes.The creation and sustainability of these lakes are significantly affected by the stability of the corresponding slopes.The present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s influence.The assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is identified.Furthermore,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical use.During the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial one.Overall,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.
基金This work was supported by the Pilot Seed Grant(Grant No.RES0049944)the Collaborative Research Project(Grant No.RES0043251)from the University of Alberta.
文摘Ore production is usually affected by multiple influencing inputs at open-pit mines.Nevertheless,the complex nonlinear relationships between these inputs and ore production remain unclear.This becomes even more challenging when training data(e.g.truck haulage information and weather conditions)are massive.In machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden layers.This study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training data.Before the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input variables.To verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark models.The DNN model with multiple hidden layers performed better than the ANN models with a single hidden layer.The DNN model outperformed the extensively applied benchmark models in predicting ore production.This can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.
文摘In order to reduce the horizontal crossing transportation problems between coal trucks and stripping trucks,large and small vehicles,and transport trucks and belt conveyors at key points of open pit mine in production,the separate transportation mode of underpass bridge and overpass steel trestle is proposed to optimize the open pit development transportation system,so as to solve the practical problems that the horizontal cross of transport vehicles causes vehicle blockage,affects production schedule and production safety.The results show that the horizontal crossing road can be changed into a separate type of overpass steel trestle,which can realize the classified transportation of large and small vehicles,reduce the traffic density,make vehicles with different functions go their own way,eliminate the hidden danger of traffic accidents,and improve the production efficiency.
文摘Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.
文摘The design and practice in supporting the cut slope of an open-pit mine wereintroduced, in which the high pressure grouting method was used in reinforcing the weak formation inthe slopes. Based on a detailed geological survey of the slope, a theoretical analysis was carriedout, and the design parameters were proposed, where the Tresca or Mohr-Coulomb yield criteria wasemployed. A patent technology, named 'Technology of high pressure and multiple grouting in differentlevels within a single hole', was employed in the construction. Anchor bars were also installed asgrouting proceeds. This method combines anchoring and grouting comprehensively and was foundsuccessful in practice.
基金partially supported by JSPS KAKENHI(Grant No.16H03153)the Limestone Association of Japan。
文摘Displacement monitoring in open-pit mines is one of the important tasks for safe management of mining processes.Differential interferometric synthetic aperture radar(DInSAR),mounted on an artificial satellite,has the potential to be a cost-effective method for monitoring surface displacements over extensive areas,such as open-pit mines.DInSAR requires the ground surface elevation data in the process of its analysis as a digital elevation model(DEM).However,since the topography of the ground surface in open-pit mines changes largely due to excavations,measurement errors can occur due to insufficient information on the elevation of mining areas.In this paper,effect of different elevation models on the accuracy of the displacement monitoring results by DInSAR is investigated at a limestone quarry.In addition,validity of the DInSAR results using an appropriate DEM is examined by comparing them with the results obtained by global positioning system(GPS)monitoring conducted for three years at the same limestone quarry.It is found that the uncertainty of DEMs induces large errors in the displacement monitoring results if the baseline length of the satellites between the master and the slave data is longer than a few hundred meters.Comparing the monitoring results of DInSAR and GPS,the root mean square error(RMSE)of the discrepancy between the two sets of results is less than 10 mm if an appropriate DEM,considering the excavation processes,is used.It is proven that DInSAR can be applied for monitoring the displacements of mine slopes with centimeter-level accuracy.
基金financially supported by the National Natural Science Foundation of China (No. 51034005)National High Technology Research and Development Program of China (No. 2012AA062004)Program for New Century Excellent Talents in University of China (No. NCET-13-1022)
文摘To study the stability of the west slope in Buzhaoba Open-Pit Mine and determine the aging stability coefficient during slide mass development, the deformation band of the west slope and the slide mass structure of the 34,600 profile are obtained on the basis of hydrology, geology, and monitoring data.The residual thrust method is utilized to calculate the stability coefficients, which are 1.225 and 1.00 under sound and transfixion conditions, respectively. According to the rock damage and fragmentation and the principle of mechanical parameter degradation, the mechanical models of the slide mass development of the hard and soft rock slopes are established. An integrated model for calculating the slope stability coefficient is built considering water, vibration, and other external factors that pertain to the structural plane damage mechanism and the generating mechanism of the sliding mass. The change curve of the stability coefficient in the slide mass development is obtained from the relevant analyses,and afterwards, the stability control measures are proposed. The analysis results indicate that in the cracking stage of the hard rock, the slope stability coefficient decreases linearly with the increase in the length Lbof the hard rock crack zone. The linear slope is positively correlated to rock cohesion c. In the transfixion stage of the soft rock, the decrease speed of the stability coefficient is positively correlated to the residual strength of the soft rock. When the slope is stable, the stability coefficient is in a quadratic-linear relationship with the decreased height Dh of the side slope and in a linear relationship with anchoring force P.
文摘Under circumstances in which both underground mining and open-pit mining are employed, the mining effects of two approaches will be superposed and the mining slope will receive several induced stress fields, which makes the sliding mechanism and deformation law of slope rock mass more complicated. This paper, targeting at the east slope of Antaibao Mine with the joint employment of underground mining and open-pit mining, aims to study the moving law of the slope rock mass and the damage mechanism to the overburden of the goaf by numerical simulation. It is supposed that models of possible damage to the slope could be explored for guidance to safety-production of the mine.
基金the Research Fund of National Natural Science Foundation of China(NSFC)(No.42277154)the project supported by graduate research and innovation foundation of Chongqing,China(No.CYB22023)+3 种基金Guizhou Province Science and Technology Planning Project(No.Guizhou science and technology cooperation support[2022]common 229)National Natural Science Foundation of Shandong Province of China(NSFC)(No.ZR2022ME188)the State Key Laboratory of Coal Resources and Safe Mining,CUMT(No.SKLCRSM22KF009)Open Fund of National Engineering and Technology Research Center for Development and Utilization of Phosphate Resources of China(No.NECP 2022-04).
文摘Two critical factors,namely intense precipitation and intricate excavation,can trigger rock mass disasters in mining operations.In this study,an indoor rainfall system was developed to precisely regulate the flow and intensity of precipitation.A large-scale model experiment was conducted on a self-designed physical simulation experiment platform to investigate the failure and instability of high-steep rock slopes under unsaturated conditions.The real-time reproduction of the progressive failure process in high-steep rock slopes enabled the determination of the critical rainfall intensity and revealed the mechanism underlying slope instability.Experiment results indicated that rainfall may be the primary factor contributing to rock mass instability,while continuous pillar mining exacerbates the extent of rock mass failure.The critical failure stage of high-steep rock slopes occurs at a rainfall intensity of 40 mm/h,whereas a rainfall exceeding 50 mm can induce critical instability and precipitation reaching up to 60 mm will result in slope failure.The improved region growing segmentation method(IRGSM)was subsequently employed for image recognition of rock mass deformation in underground mines.Herein an error comparison with the simple linear iterative cluster(SLIC)superpixel method and the original region growing segmentation method(ORGSM)showed that the average identification error in the X and Y directions by the method was reduced significantly(1.82%and 1.80%in IRGSM;4.70%and 6.26%in SLIC;9.45%and 12.40%in ORGSM).Ultimately,the relationship between rainfall intensity and failure probability was analyzed using the Monte Carlo method.Moreover,the stability assessment criteria of rock slope under unsaturated condition were quantitatively and accurately evaluated.
基金supported by the National Key Research and Development Program of China(Nos.2022YFC2903902 and 2022YFC2903903)the National Natural Science Foundation of China(Nos.U1903216 and 52174070).
文摘The significant difference between the mechanical properties of soft rock and hard rock results in the complexity of the failure mode of the anti-dip layered slope with soft and hard rock interbedding.In order to reveal the landslide mechanism,taking the north slope of Fushun West Open-pit Mine as an example,this paper analyzed the failure mechanism of different landslides with monitoring and field surveys,and simulated the evolution of landslides.The study indicated that when the green mudstone(hard rock)of the anti-dip slope contains siltized intercalations(soft rock),the existence of weak layers not only aggravates the toppling deformation of anti-dip layered slope with high dip,but also causes the shear failure of anti-dip layered slope with stable low dip.The shear failure including subsidence induced sliding and wedge failure mainly exists in the unloading zone of the slope.Its failure depth and failure time were far less than that of toppling failure.In terms of the development characteristics of deformation,toppling deformation has the long-term and progressive characteristics,but shear failure deformation has the abrupt and transient characteristics.This study has deepened the understanding of such slope landslide mechanism,and can provide reference for similar engineering.
文摘Estimation of stability of natural slopes, embankments, dams and open-pit slopes during earthquakes are complex and non-linear problems, therefore physical modeling is used for decision of it. As a result of physical modeling the pattern of seismic vibrations impact based on the movement process of probable collapse prism delineated by the most stressed plane of sliding has been established. Particular recommendations on the basis of safety factors selection in seismoactive zones are given.
基金supported by the National Natural Science Foundation of China(Grant Nos.41672273,42177137)the Fundamental Research Funds for the Central Universities(22120180313)+1 种基金the support from China Scholarship Council(CSC)(202106260151)substantially supported by the Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education(Tongji University)。
文摘Due to the loose structure,high porosity and high permeability of soil-rock mixture slope,the slope is unstable and may cause huge economic losses and casualties.The h-type anti-slide pile is regarded as an effective means to prevent the instability of soilrock mixture slope.In this paper,a centrifuge model test was conducted to investigate the stress distribution of the h-type anti-slide pile and the evolution process of soil arching during the loading.A numerical simulation model was built based on the similar relationship between the centrifuge model and the prototype to investigate the influence factors of the pile spacing,anchored depth,and crossbeam stiffness,and some recommendations were proposed for its application.The results show that the bending moment distribution of the rear pile exhibits Wshaped,while for the front pile,its distribution resembles V-shaped.The soil arching evolution process during loading is gradually dissipated from bottom to top and from far to near.During the loading,the change of bending moment can be divided into three stages,namely,the stabilization stage,the slow growth stage,and the rapid growth stage.In engineering projects,the recommended values of the pile spacing,anchored depth,and crossbeam stiffness are 4.0d,2.0d,and 2.0EI,where d and EI are the diameter and bending stiffness of the h-type anti-slide pile respectively.
文摘In the process of intelligent mine construction in open-pit mine, in order to improve the safety monitoring ability of mine transportation system, solve the problems of large human interference and blind Angle detection by existing conventional monitoring methods, this paper establishes an open-pit mine monitoring data set, and proposes a real-time intelligent monitoring model based on UAV. The reasoning component with strong computing power and low power consumption is selected, and the lightweight object detection model is selected for the experiment. A quantitative standard of dynamic energy consumption detection by evaluation algorithm is proposed. Through experimental comparison, it is found that YOLOv4-tiny has the highest comprehensive grade in detection accuracy, speed, energy consumption and other aspects, which is suitable for application in the above model.