The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Hao Zhou - One of the best experts on this subject based on the ideXlab platform.
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experiment on the failure process of Jointed Rock specimen under compression and numerical test
GeoShanghai International Conference, 2018Co-Authors: Hao Zhou, Weishen Zhu, Yang Song, Qimin Wang, Yanqing MenAbstract:Numerous fissures, joints and faults exist widely in natural Rock masses which played an important role in the geotechnical engineering. Experimental and numerical methods are very important to the researches of Jointed Rock mass. The improvement measures of Discontinuous Deformation Analysis numerical method make it more suitable for the failure process of Jointed Rock mass. A Rock specimen was tested under compression by experimental method and numerical method. The numerical test of failure process that improved Discontinuous Deformation Analysis method matches well with the experiment of Rock specimen. The process proved that the improved Discontinuous Deformation Analysis method could effectively simulate the failure process of Jointed Rock mass. Additionally, detailed initiation and propagation process of secondary cracks were shown in the research. The initiation and propagation of secondary wing cracks were significant behaviors during the failure process of Jointed Rock mass. Detailed crack extending process had been discussed deeply and it could be useful for the theoretical research.
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Numerical Study on Crack Propagation in Brittle Jointed Rock Mass Influenced by Fracture Water Pressure
Materials, 2015Co-Authors: Hao Zhou, Weishen Zhu, Jian LiuAbstract:The initiation, propagation, coalescence and failure mode of brittle Jointed Rock mass influenced by fissure water pressure have always been studied as a hot issue in the society of Rock mechanics and engineering. In order to analyze the damage evolution process of Jointed Rock mass under fracture water pressure, a novel numerical model on the basis of secondary development in fast Lagrangian analysis of continua (FLAC3D) is proposed to simulate the fracture development of Jointed Rock mass under fracture water pressure. To validate the feasibility of this numerical model, the failure process of a numerical specimen under uniaxial compression containing pre-existing fissures is simulated and compared with the results obtained from the lab experiments, and they are found to be in good agreement. Meanwhile, the propagation of cracks, variations of stress and strain, peak strength and crack initiation principles are further analyzed. It is concluded that the fissure water has a significant reducing effect on the strength and stability of the Jointed Rock mass.
Penghai Zhang - One of the best experts on this subject based on the ideXlab platform.
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Characterization on Jointed Rock masses based on PFC2D
Frontiers of Structural and Civil Engineering, 2013Co-Authors: P. Wang, Tianhong Yang, Honglei Liu, Penghai ZhangAbstract:Geometrical parameters of discontinuities, such as spacing, length, dip and fault throw between joints have a great influence on the mechanical behavior of Jointed Rock masses. Accurate characterization for discontinuities is important for investigate the stability of Rock masses. In this paper, the PFC2D is combined with joint network generation method to examine the mechanical behaviors of Jointed mass. Taking Miaogou Open-pit Mine as an example, the information and statistical distributions of discontinuities of the slope Rock masses are measured by ShapeMetriX3D measuring tool. Then, the automatic generation algorithm of random joints network based on the Monte-Carlo method is proposed using the programming language (FISH) embedded within PFC2D. This algorithm could represent the discontinuities compared with the geological surveys. In simulating the compression test of a Jointed Rock sample, the mechanical behavior and crack propagation were investigated. The results reveal that the failure mode and crack propagation of the Jointed Rock are dominated by the distribution of joints in addition to the intact Rock properties. The simulation result shows the feasibility of the joints generating method in application to Jointed Rock mass.
Weishen Zhu - One of the best experts on this subject based on the ideXlab platform.
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experiment on the failure process of Jointed Rock specimen under compression and numerical test
GeoShanghai International Conference, 2018Co-Authors: Hao Zhou, Weishen Zhu, Yang Song, Qimin Wang, Yanqing MenAbstract:Numerous fissures, joints and faults exist widely in natural Rock masses which played an important role in the geotechnical engineering. Experimental and numerical methods are very important to the researches of Jointed Rock mass. The improvement measures of Discontinuous Deformation Analysis numerical method make it more suitable for the failure process of Jointed Rock mass. A Rock specimen was tested under compression by experimental method and numerical method. The numerical test of failure process that improved Discontinuous Deformation Analysis method matches well with the experiment of Rock specimen. The process proved that the improved Discontinuous Deformation Analysis method could effectively simulate the failure process of Jointed Rock mass. Additionally, detailed initiation and propagation process of secondary cracks were shown in the research. The initiation and propagation of secondary wing cracks were significant behaviors during the failure process of Jointed Rock mass. Detailed crack extending process had been discussed deeply and it could be useful for the theoretical research.
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Numerical Study on Crack Propagation in Brittle Jointed Rock Mass Influenced by Fracture Water Pressure
Materials, 2015Co-Authors: Hao Zhou, Weishen Zhu, Jian LiuAbstract:The initiation, propagation, coalescence and failure mode of brittle Jointed Rock mass influenced by fissure water pressure have always been studied as a hot issue in the society of Rock mechanics and engineering. In order to analyze the damage evolution process of Jointed Rock mass under fracture water pressure, a novel numerical model on the basis of secondary development in fast Lagrangian analysis of continua (FLAC3D) is proposed to simulate the fracture development of Jointed Rock mass under fracture water pressure. To validate the feasibility of this numerical model, the failure process of a numerical specimen under uniaxial compression containing pre-existing fissures is simulated and compared with the results obtained from the lab experiments, and they are found to be in good agreement. Meanwhile, the propagation of cracks, variations of stress and strain, peak strength and crack initiation principles are further analyzed. It is concluded that the fissure water has a significant reducing effect on the strength and stability of the Jointed Rock mass.
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Crack Propagation of Jointed Rock and Application
Applied Mechanics and Materials, 2011Co-Authors: Jing Wang, Weishen Zhu, Hai PingAbstract:The excavation engineering in Jointed Rock masses, due to the changes in its original stress state, the preexisting fissures will expand and new fissures may emerge, which will degrade its mechanical and strength properties. This paper uses the DDARF method to preinstall fissures of different numbers and spacing in the Rock block, then studies the crack initiation, expansion, transfixion and the destruction process by numerical modeling experiment, and finds the relevant stress strain curve. It also studies the influence of the numbers of fissures and different spacing and the influence of lateral compression on the test specimen to find the strength envelope of the test specimen. The parameters are applied in a case study. The differences in the failure behaviors of the intact and Jointed Rock masses after cavern excavation are analyzed and compared.
Pijush Samui - One of the best experts on this subject based on the ideXlab platform.
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Intelligent Models Applied to Elastic Modulus of Jointed Rock Mass
Advances in Civil and Industrial Engineering, 2018Co-Authors: Jagan Jayabalan, Sanjiban Sekhar Roy, Pijush Samui, Pradeep KurupAbstract:Elastic Modulus (Ej) of Jointed Rock mass is a key parameter for deformation analysis of Rock mass. This chapter adopts three intelligent models {Extreme Learning Machine (ELM), Minimax Probability Machine Regression (MPMR) and Generalized Regression Neural Network (GRNN)} for determination of Ej of Jointed Rock mass. MPMR is derived in a probability framework. ELM is the modified version of Single Hidden Layer Feed forward network. GRNN approximates any arbitrary function between the input and output variables. Joint frequency (Jn), joint inclination parameter (n), joint roughness parameter (r), confining pressure (s3) (MPa), and elastic modulus (Ei) (GPa) of intact Rock have been taken as inputs of the ELM, GRNN and MPMR models. The output of ELM, GRNN and MPMR is Ej of Jointed Rock mass. In this study, ELM, GRNN and MPMR have been used as regression techniques. The developed GRNN, ELM and MPMR have been compared with the Artificial Neural Network (ANN) models.
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Modeling of Elastic Modulus of Jointed Rock Mass: Gaussian Process Regression Approach
International Journal of Geomechanics, 2014Co-Authors: M. S. Mohan Kumar, Madhav R. Bhatt, Pijush SamuiAbstract:AbstractThe elastic modulus (Ej) of a Jointed Rock mass is an important parameter for Rock mechanics. This study examines the capability of Gaussian process regression (GPR) for determination of the Ej of Jointed Rock masses. The GPR is a Bayesian nonparametric model. The joint frequency (Jn), joint inclination parameter (n), joint roughness parameter (r), confining pressure (σ3), and elastic modulus (Ei) of intact Rock are considered as inputs of the GPR. The output of the GPR is the Ej of Jointed Rock masses. The developed GPR has been compared with the artificial neural network (ANN) models. Variance of the predicted Ej of Jointed Rock masses is obtained from the GPR. The results show that the developed GPR is a promising tool for the prediction of the Ej of Jointed Rock masses.
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Multivariate Adaptive Regression Spline (Mars) for Prediction of Elastic Modulus of Jointed Rock Mass
Geotechnical and Geological Engineering, 2012Co-Authors: Pijush SamuiAbstract:This article presents multivariate adaptive regression spline (MARS) for determination of elastic modulus (Ej) of Jointed Rock mass. MARS is a technique to estimate general functions of high-dimensional arguments given sparse data. It is a nonlinear and non-parametric regression methodology. The input variables of model are joint frequency (Jn), joint inclination parameter (n), joint roughness parameter (r), confining pressure (σ3) and elastic modulus (Ei) of intact Rock. The developed MARS gives an equation for determination of Ej of Jointed Rock mass. The results from the developed MARS model have been compared with those of artificial neural networks (ANNs) using average absolute error. The developed MARS gives a robust model for determination of Ej of Jointed Rock mass.
P. Wang - One of the best experts on this subject based on the ideXlab platform.
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Characterization on Jointed Rock masses based on PFC2D
Frontiers of Structural and Civil Engineering, 2013Co-Authors: P. Wang, Tianhong Yang, Honglei Liu, Penghai ZhangAbstract:Geometrical parameters of discontinuities, such as spacing, length, dip and fault throw between joints have a great influence on the mechanical behavior of Jointed Rock masses. Accurate characterization for discontinuities is important for investigate the stability of Rock masses. In this paper, the PFC2D is combined with joint network generation method to examine the mechanical behaviors of Jointed mass. Taking Miaogou Open-pit Mine as an example, the information and statistical distributions of discontinuities of the slope Rock masses are measured by ShapeMetriX3D measuring tool. Then, the automatic generation algorithm of random joints network based on the Monte-Carlo method is proposed using the programming language (FISH) embedded within PFC2D. This algorithm could represent the discontinuities compared with the geological surveys. In simulating the compression test of a Jointed Rock sample, the mechanical behavior and crack propagation were investigated. The results reveal that the failure mode and crack propagation of the Jointed Rock are dominated by the distribution of joints in addition to the intact Rock properties. The simulation result shows the feasibility of the joints generating method in application to Jointed Rock mass.
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Finite element analysis of Jointed Rock masses and engineering application
International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1993Co-Authors: W. Zhu, P. WangAbstract:Abstract In this paper, regularly Jointed Rock masses are regarded as composed of isotropic Rock elements and equivalent anisotropic Jointed Rock elements. On the basis of analyzing the deformation and strength of Jointed Rock elements, fundamental formulae are derived for equivalent deformation and equivalent strength: thus, an equivalent continuum model is presented. By non-linear FEM analysis the simulation is performed for the mechanical properties of Jointed Rock masses. The validity of the model is verified by means of physical model tests. This numerical model has been applied in for strength prediction and stability analysis for two typical engineering Jointed Rock masses, with satisfactory results.
