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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 215-222页

作者： Liu Shi Xu Jinyu Lv Xiaocong Department of Airfi eld and Building Engineering Air Force Engineering University College of mechanics and Civil Architecture Northwest Polytechnic University

In order to investigate the dynamic mechanical properties of amphibolite and sericite-quartz schist under confi ning pressure, two rocks are subjected to impact loadings with different strain rates and confi ning pressures by using split Hopkinson pressure bar equipment with a confi ning pressure device. Based on the experimental results, the stress-strain curves are analyzed and the effects of confi ning pressure and strain rates on the dynamic compressive strength, peak strain and failure mode are summarized. The results show that:(1) The characteristics of two rocks in the ascent stage of the stressstrain curve are basically the same, but in the descent stage, the rocks gradually show plastic deformation characteristics as the confi ning pressure increases.(2) The dynamic compressive strength and peak strain of two rocks increase as the strain rate increases and the confi ning pressure effects are obvious.(3) Due to the effect of confi ning pressure, the normal stress on the damage surface of the rock increases correspondingly, the bearing capacity of the crack friction exceeds the material cohesion and the slippage of the fractured rock is controlled, which all lead to the compression and shear failure mode of rock. The theoretical analysis and experimental methods to study the dynamic failure mode and other related characteristics of rock are useful in developing standards for engineering practice.

关键词： rock mechanics SHPB with confi ning pressure device confi ning pressure strain rate impact loading

Modeling rock specimens through 3D printing: Tentative experiments and prospects

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Acta Mechanica Sinica 2016年第1期32卷 101-111页

作者： Quan Jiang Xiating Feng Lvbo Song Yahua Gong Hong Zheng Jie Cui State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of Sciences

Current developments in 3D printing （3DP） technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows：（1） compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and （2） com- pressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in produc- ing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample （such as a natural rock joint）. These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the sim- ulation of similar material modeling experiments.

关键词： rock mechanics Similar material 3Dprinting Geotechnical model Deformation and failure

Deformation and failure of stratified weak roof strata of longwall roadway

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Journal of University of Science and Technology Beijing 2007年第5期14卷 387-394页

作者： Tingkan Lu Yuzhou Liu Fusheng Xu School of Energy Science and Engineering Henan Polytechnic University Jiaozuo 454000 China School of Environment and Resources Chongqin University Chongqin 400044 China Department of Financial Operations Kai Luan Group Ltd. Tangshan 063018 China

A comprehensive underground monitoring was conducted in a coal mine. The purpose of this research was to clarify the deformation and failure behavior of stratified weak roof strata of longwall roadway in adverse ground conditions. The field investigation incorporating a range of geotechnical instrumentation was conducted over a period of time ever since the formation of opening the site was buried into the goaf of a retreating longwall panel. The roof layer deformation and failure characteristics associated with the three stages of heading development, after development and before extraction, as well as after longwall extraction were identified on the basis of field investigation and analytical study, the results clearly demonstrated that how the roof deformation and failure progress were strongly related to these three stages of the mining activities mentioned.

关键词： rock mechanics longwall roadway roof deformation field monitoring

Laboratory tests to study the influence of rock stress confinement on the performances of TBM discs in tunnels

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 253-259页

作者： N. Innaurato C. Oggeri P. Oreste R. Vinai DITAG Politecnico di Torino Corso Duca degli Abruzzi 24 Turin Italy

To clarify some aspects of rock destruction with a disc acting on a high confined tunnel face, a series of tests were carried out to examine fracture mechanisms under an indenter that simulates the tunnel boring machine （TBM） tool action, in the presence of an adjacent groove, when a state of stress （lateral confinement） is imposed on a rock sample. These tests proved the importance of carefully establishing the optimal distance of grooves produced by discs acting on a confined surface, and the value （as a mere order of magnitude） of the increase of the thrust to produce the initiation of chip formation, as long as the confinement pressure becomes greater.

关键词： tunnels boring machines rock mechanics stress analysis

Particle simulation of the failure process of brittle rock under triaxial compression

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 507-513页

作者： Ming Xia Ke-ping Zhou School of Resources and Safety Engineering Central South University Changsha 410083 China Ma＇anshan Institute of Mining Research Ma＇anshan 243004 China

In order to investigate the failure process of brittle rock under triaxial compression through both experimental and numerical approaches, the particle simulation method was used in numerical simulations and the simulated results were compared with those of the experiment. The numerical simulation results, such as fracture propagation, microcrack distribution, stress-strain response, and damage patterns, were discussed in detail. The simulated results under various confining pressures （0-60 MPa） are in good agreement with the experimental results. The simulated results reveal that rock failure is caused by axial splitting under uniaxial compression. As the confining pressure increases, rock failure occurs in a few localized shear planes and the rock mechanical behavior is changed from brittle to ductile. Consequently, the peak failure strength, microcrack numbers, and the shear plane angle increase, but the ratio of tensile to shear microcracks decreases. The damage formation during the compression simulations indicates that the particle simulation method can produce similar behaviors as those observed through laboratory compression tests.

关键词： rock mechanics compression testing failure fracture modes simulation microcracks

Geomechanical design of a room and rib pillar granite mine

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Journal of University of Science and Technology Beijing 2008年第2期15卷 97-103页

作者： Daniele Peila Claudia Guardini Sebastiano Pelizza Tunnelling Underground Space Center Department of EnvironmentLand and Geotechnology Engineering Politecnico di Torino Tunnelling Underground Space Center Department of EnvironmentLand and Geotechnology EngineeringPolitecnico di TorinoTorinoItaly

The geomechanical and stability design of an underground granite mine located in Canal San Bovo （Trento district, Northeastern Italy） was described. The exploitation of the granite, which is used in the ceramic industry, was carried out by the rooms and rib pillars method. The rooms are 12 m wide while the pillars are 11 m wide and they cross the main discontinuity set of the rock mass in the perpendicular direction. To verify the stability condition of an underground mine, it is necessary to carry out the calcula- tions that are able to check both the local and global stability of the rock mass. In the studied example, this approach has been applied with the development of analytical and numerical parametric analyses and it has permitted to get the best orientation and to design the size of rooms and pillars.

关键词： mining room and pillar rock mechanics stability analysis

UNCONFINED SEEPAGE ANALYSIS OF DISCONTINUOUS rock SLOPE

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Journal of Hydrodynamics 2000年第3期12卷 75-86页

作者： Chen, Shenghong Wang, Weiming She, Chengxue Xu, Mingxi Wuhan Univ of Hydraulic and Electrical Engineering Wuhan China

Unconfined seepage field of arch dam abutment slope was studied. This paper is composed of two parts. The first part concerns with the numerical methods used in the analysis, which includes the identification of rock blocky system and the algorithm of the unconfined seepage flow in the discontinuity network with the consideration of the grouting curtain and drainage curtain. In the second part a complicated arch dam abutment slope was studied, for which the seepage flow field characteristics was analyzed and the seepage control system was evaluated.

关键词： Arch dams Flow of water Leakage (fluid) Numerical analysis rock mechanics

Logging prediction and evaluation of fracture toughness for the shales in the Longmaxi Formation, Southern Sichuan Basin

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Petroleum 2021年第3期7卷 254-262页

作者： Jian Xiong Kaiyuan Liu Changyou Shi Xiangjun Liu Linlin Huang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina Geophysical Technology Research Center of BGP INC China National Petroleum CorporationChengduChina

The mode-I fracture toughness is of great significance for evaluating the fracturing ability of shale *** this study,the mode-I fracture toughness of the shale in the Lower Silurian Longmaxi Formation,Southern Sichuan Basin was determined with the Cracked Chevron Notched Brazilian Disc(CCNBD).Based on the experimental data,the relationships among the mode-I fracture toughness,the density,the acoustic time and the clay mineral content were *** shale samples for fracture toughness test from cores were commonly limited,the investigation of fracture toughness using well logs was ***,a prediction model was proposed by correlating the fracture toughness with well logs *** results indicate that the fracture toughness of shale samples is from 0.4744 MPa$m1/2 to 1.0607 MPa$m1/2 with an average of 0.7817 MPa$m1/2,indicating that the anisotropy of fracture toughness of the Longmaxi Formation *** clay mineral content and the density have a positive effect on the fracture toughness,whereas the acoustic time plays a negative role on the fracture *** clay mineral content has an important effect on the relationships among fracture toughness,acoustic time and *** prediction model can provide continuous data of mode-I fracture toughness along the wellbore for field hydraulic fracturing operation,and it has certain guiding significance in the exploration and development of oil and gas reservoirs.

关键词： rock mechanics Longmaxi formation shale CCNBD Mode-I fracture Toughness Prediction method

Study on Estimation Method of rock Mass Discontinuity Shear Strength Based on Three-Dimensional Laser Scanning and Image Technique

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Journal of Earth Science 2012年第6期23卷 908-913页

作者：唐辉明葛云峰王亮清苑谊黄磊孙淼军 Faculty of Engineering China University of Geosciences Center of Geological Environment Department of Land and Resource of Hubei Province

The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation methods, a new approach based on the shadow area percentage （SAP） that can be used to quantify surface roughness is proposed in this article. Firstly, by the help of laser scanning technique, the three-dimensional model of the surface of rock discontinuity was established. Secondly, a light source was simulated, and there would be some shadows produced on the model surface. Thirdly, to obtain the value of SAP of each specimen, the shadow detection technique was introduced for use. Fourthly, compared with the result from direct shear testing and based on statistics, an empirical for- mula was found among SAP, normal stress, and shear strength. Data of Yujian （~ River were used as an example, and the following conclusions have been made. （1） In the case of equal normal stress, the peak shear stress is positively proportional to the SAP. （2） The formula for estimating was derived, and the predictions of peak-shear strength made with this equation well agreed with the experimental re- suits obtained in laboratory tests.

关键词： rock mechanics rock mass discontinuity shear strength estimation method three-dimensional laser scanning technique image recognition technique.

Experimental investigation of creep behavior of clastic rock in Xiangjiaba Hydropower Project

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Water Science and Engineering 2015年第1期8卷 55-62页

作者： Yu Zhang Wei-ya Xu Jian-fu Shao Hai-bin Zhao Wei Wang College of Pipeline and Civil Engineering China University of Petroleum Geotechnical Research Institute Hohai University Hunan Provincial Key Laboratory of Key Technology on Hydropower Development

There are many fracture zones crossing the dam foundation of the Xiangjiaba Hydropower Project in southwestern China. Clastic rock is the main media of the fracture zone and has poor physical and mechanical properties. In order to investigate the creep behavior of clastic rock, triaxial creep tests were conducted using a rock servo-controlling rheological testing machine. The results show that the creep behavior of clastic rock is significant at a high level of deviatoric stress, and less time-dependent deformation occurs at high confining pressure. Based on the creep test results, the relationship between axial strain and time under different confining pressures was investigated, and the relationship between axial strain rate and deviatoric stress was also discussed. The strain rate increases rapidly, and the rock sample fails eventually under high deviatoric stress. Moreover, the creep failure mechanism under different confining pressures was analyzed. The main failure mechanism of clastic rock is plastic shear, accompanied by a significant compression and ductile dilatancy. On the other band, with the determined parameters, the Burgers creep model was used to fit the creep curves. The results indicate that the Burgers model can exactly describe the creep behavior of clastic rock in the Xiangjiaba Hydropower Project.

关键词： rock mechanics Clastic rock Creep behavior Triaxial creep test Burgers creep model Xiangjiaba Hydropower Project