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Analysis profile of the fully grouted rock bolt in jointed rock using analytical and numerical methods

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International Journal of Mining Science and Technology 2014年第5期24卷 609-615页

作者： Ghadimi Mostafa shahriar kourosh Jalalifar Hossein Department of Mine Science and Research Branch Islamic Azad University Faculty of Mining Metallurgy and Petroleum Engineering Amir Kabir University of Technology Department of Petroleum and Mining Engineering Environmental and Energy Research Center Shahid Bahonar University of Kerman

The purpose of this study was to investigate the effect of bolt profile on load transfer mechanism of fully grouted bolts in jointed rocks using analytical and numerical methods. Based on the analytical method with development of methods, a new model is presented. To validate the analytical model, five different profiles modeled by ANSYS software. The profile of rock bolts T3 and T4with load transfer capacity,respectively 180 and 195 kN in the jointed rocks was selected as the optimum profiles. Finally, the selected profiles were examined in Tabas Coal Mine. FLAC analysis indicates that patterns 6+7 with2 NO flexi bolt 4 m better than other patterns within the faulted zone.

关键词： Fully grouted bolt Load transfer mechanism Jointed rocks Analytical and numerical methods

Cracks coalescence mechanism and cracks propagation paths in rock-like specimens containing pre-existing random cracks under compression

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Journal of Central South University 2014年第6期21卷 2404-2414页

作者： Hadi Haeri kourosh shahriar Mohammad Fatehi Marji Parviz Moarefvand Department of Mining Engineering Science and Research BranchIslamic Azad University Department of Mining and Metallurgical Engineering Amirkabir University of Technology Mine Exploitation Engineering Department Faculty of Mining and MetallurgyInstitution of EngineeringYazd University

The mechanism of cracks propagation and cracks coalescence due to compressive loading of the brittle substances containing pre-existing cracks （flaws） was modeled experimentally using specially made rock-like specimens from Portland Pozzolana Cement （PPC）. The breakage process of the specimens was studied by inserting single and double flaws with different inclination angles at the center and applying uniaxial compressive stress at both ends of the specimen. The first crack was oriented at 50＆#176; from the horizontal direction and kept constant throughout the analysis while the orientation of the second crack was changed. It is experimentally observed that the wing cracks are produced at the first stage of loading and start their propagation toward the direction of uniaxial compressive loading. The secondary cracks may also be produced in form of quasi-coplanar and/or oblique cracks in a stable manner. The secondary cracks may eventually continue their propagation in the direction of maximum principle stress. These experimental works were also simulated numerically by a modified higher order displacement discontinuity method and the cracks propagation and cracks coalescence were studied based on Mode I and Mode II stress intensity factors （SIFs）. It is concluded that the wing cracks initiation stresses for the specimens change from 11.3 to 14.1 MPain the case of numerical simulations and from 7.3 to 13.8 MPa in the case of experimental works. It is observed that cracks coalescence stresses change from 21.8 to 25.3 MPa and from 19.5 to 21.8 MPa in the numerical and experimental analyses, respectively. Comparing some of the numerical and experimental results with those recently cited in the literature validates the results obtained by the proposed study. Finally, a numerical simulation was accomplished to study the effect of confining pressure on the crack propagation process, showing that the SIFs increase and the crack initiation angles change in this case.

关键词： crack propagation crack coalescence rock-like specimen numerical simulation experiment

Thermo-hydro-mechanical modeling of fault discontinuities using zero-thickness interface element

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第1期12卷 74-88页

作者： Ali Ranjbar Hossein Hassani kourosh shahriar Mohammad Javad Ameri Shahrabi Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Department of Mining and Metallurgy Engineering Amirkabir University of TechnologyTehranIran

In this paper,a coupled thermo-hydro-mechanical(THM)simulation in a faulted deformable porous medium is *** model involves solving the mass conservation,linear momentum balance,and energy balance equations which are derived from the Biot’s consolidation *** pore pressure,solid displacement,and temperature are chosen as initial variables in these equations,and the finite element method in combination with the interface element is used for spatial discretization of continuous and discontinuities(fault)parts of the medium to solve the *** main purpose of this study is providing precise formulations,applicability,and ability of the triple-node zero-thickness interface element in THM modeling of *** should be noted that the system of equations is solved using a computer code written in Matlab *** order to verify the developed method,simulations of index problems such as Mandel’s problem,and coupled modeling of a faulted porous medium and a faulted aquifer are *** modeling results obtained from the developed method show a very good agreement with those by other modeling methods,which indicates its accuracy.

关键词： Thermo-hydro-mechanical(THM) simulation Geomechanical coupling Zero-thickness element Joint element Finite element

An estimation of the penetration rate of rotary drills using the Specific Rock Mass Drillability index

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International Journal of Mining Science and Technology 2012年第2期22卷 187-193页

作者： Cheniany Alireza Hasan Khoshrou Seyed shahriar kourosh Khademi Hamidi Jafar Department of Mining and Metallurgy Engineering Amirkabir University of TechnologyTehranIran Mining Engineering Department Faculty of EngineeringTarbiat Modares UniversityTehranIran

The main purpose of the present study was to provide a practical, convenient drillability prediction model based on rock mass characteristics, geological sampling from blast holes, and drill operational factors. Empirical equations that predict drill penetration rate have been developed using statistical analyses of data from the Sarcheshmeh Copper Mine. Seven parameters of the rock or rock mass, including uniaxial compressive strength （UCS） of the rock, Schmidt hammer hardness value, quartz content, fragment size （dso）, alteration, and joint dip, are included in the model along with two operational parameters of the rotary drill, bit rotational speed and thrust. These parameters were used to predict values of the newly developed Specific Rock Mass Drillability （SRMD） index. Comparing measured SRMD values to those pre- dicted by the multi-parameter linear, or nonlinear, regression models showed good agreement. The cor- relation coefficients were 0.82 and 0.81. resoectively.

关键词： Rotary drillingPenetration rateSpecific Rock Mass Drillability (SRMD) indexSarcheshmeh Copper Mine

Erratum to: Cracks coalescence mechanism and cracks propagation paths in rock-like specimens containing pre-existing random cracks under compression

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Journal of Central South University 2014年第10期21卷 4052-4052页

作者： Hadi Haeri kourosh shahriar Mohammad Fatehi Marji Parviz Moarefv Department of Mining Engineering Science and Research Branch Islamic Azad University Department of Mining and Metallurgical Engineering Amirkabir University of Technology Mine Exploitation Engineering Department Faculty of Mining and Metallurgy Institution of EngineeringYazd University

Erratum to:*** Univ.(2014)21:2404-2414DOI:10.1007/s11771-014-2194-yThe original version of this article unfortunately contained a *** E-mail addresses of the corresponding author are *** corrected information of the c... 详细信息

关键词： Cracks coalescence mechanism and cracks propagation paths in rock-like specimens containing pre-existing random cracks under compression Erratum to