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Exploration, development, structural geology
Anchoring Characteristic of Tension-Type Anchor Cable and Grout Lengthdesign
Liu, Xiumin (State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences) | Zhou, ichao (State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences) | Chen, Congxin (State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences) | Zheng, Yun (State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences) | Xia, Kaizhong (State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences)
Abstract Currently the design of tension-type anchor cable based on the assumption that anchoring force uniformly distributed in the anchorage segment, but field test show it unevenly in fact. This study established an elastic mechanical model for the tension-type anchor in rock mass and gained anchoring force distribution expression. The exponential expression shows that anchoring force concentrates in part length of the anchorage segment, and the maximum of it is proportional to the freedom segment length and pre-stressing force, inversely proportional to surrounding rock's stiffness and anchor hole's radius. Then, according to the anchoring force distribution law, the anchorage segment was divided into effective anchorage segment and synergistic anchorage segment two parts. A calculation formula for the effective anchorage length was proposed correspondingly. It was found that this length mainly determined by the rigidity of surrounding rock and buried depth of anchorage segment. Designed grout length must be longer than it. Finally, by referenced to a number of engineering examples, a rational range of grout length for tension-type anchor cable was suggested in soft rock and hard rock respectively. 1 Introduction Recently, tension-type pre-stressed anchor has been widely used in the reinforcement engineering such as slope, excavation and caverns, for it has many advantages compared to the original one, e.g. large anchoring tonnage, deep anchoring region and simple construction. In existing national design codes [1], the anchoring force that a certain length anchor segment provides is calculated based on the assumption that bond strength uniformly distributes along the anchoring segment between the grout and rock formations or steel strand. However, many trials [2–3] and theoretical [4–5] studies have shown that the side resistance on anchoring segment is not evenly distributed but concentrated within a small region. So, there is no adequate theoretical basis for the design of anchorage segment in accordance with the assumption, and it is necessary to do in-depth study of the distribution law of pre-stressed anchorage force which can be used as theoretical reference for pre-stressed anchor design. I.W. Farmer [6], J. Zhongxin [7], H. Siming [8], Y. Chunan [9], etc. put forward the anchor shear stress distribution expression through theoretical analysis. All those theoretical study is based on stress analysis of the whole grouted anchor. Under pre-stressing tension load, the anchorage segment of anchor is embedded deep in rock mass to form a tensile stress concentration area, and the free segment end is locked on the rock surface to forma compressive stress concentrated area. Obviously, for bearing load actively, the tension-type pre-stressed anchor has different mechanical behavior from common grouted anchor.
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (0.49)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.36)
Three-Dimensional Thermomechanical Modelling of High-Level Waste Emplacement in a Salt Dome
Heusermann, S. (Federal Institute for Geosciences and Natural Resources (BGR)) | Eickemeier, R. (Federal Institute for Geosciences and Natural Resources (BGR)) | Nipp, H.-K. (Federal Institute for Geosciences and Natural Resources (BGR)) | Fahland, S. (Federal Institute for Geosciences and Natural Resources (BGR))
Abstract Geoscientific investigations at the Gorleben salt dome have been conducted to prove its suitability as a repository for high-level radioactive waste. Part of the investigation is the geotechnical safety analysis to assess the integrity of the geological barrier under thermal loading caused by heat-generating wastes. To this end, the geological structure of the rock, as well as appropriate constitutive material models must be taken into account to analyse the long-term deformation and dilatancy of the rock salt. The paper describes two numerical 3-D models of the emplacement of wastes. The first model deals with the emplacement in drifts located at the 860-m level. The second model considers the borehole disposal concept involving the emplacement of waste canisters in vertical boreholes. The calculations were performed for a time period of 10,000 years. The calculated stresses are used to evaluate the integrity of the salt barrier. For this purpose, the dilatancy criterion and the hydraulic criterion are considered. Introduction Geoscientific surface exploration looking at the suitability of the Gorleben salt dome as a potential site for a geologic repository for high radioactive heat-generating waste began in 1977. This work was followed up by underground exploration of the site beginning in 1983. The explorationwas interrupted for ten years from 2000 to 2010 as part of a moratorium and was continued in November 2010. The Federal Office for Radiation Protection (BfS) is responsible for the planning, construction, and operation of the Gorleben site. The Federal Institute for Geosciences and Natural Resources (BGR) deals with the primary geoscientific questions, e.g. geology, geophysics, geotechnics, and modelling. In parallel to the continuation of the investigation activities, the Federal Ministry of the Environment, Nature Conservation and Nuclear Safety (BMU) initiated the project "Preliminary Safety Analysis of the Gorleben Site (VSG)" to assess the safety of the Gorleben salt dome on the basis of current knowledge. In the past, model calculations have been undertaken by BGR to analyse the mechanical behaviour of mine components like shafts and drifts. Thermally induced stresses and strains have been predicted on a large scale. These stresses and strains will be caused over large time periods by the disposal of heatgenerating high-level waste and are basic parameters for evaluating the long-term mechanical integrity of the salt barrier. The paper describes two different numerical 3-D models of the Gorleben salt dome which have been used for different kinds of waste emplacement to analyse the far-field integrity of the salt barrier. Both models describe a characteristic geological cross section of the salt dome considering the main geological layers of the salt structure and the overburden in a detailed way. The first model deals with the emplacement of Pollux casks in drifts located at the 860-m level. The second model considers the borehole disposal concept involving the emplacement of BSK3 fuel element canisters in vertical boreholes at a depth of 870 to 1170 m. The model calculations have been carried out using the special purpose JIFE code (Faust et al. 2011).
- Geology > Structural Geology > Tectonics > Salt Tectonics (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
Abstract Zagros Water Conveyance tunnel in western Iran crosses a broad and vast aquifer. This TBM burrowed tunnel has long drained the region's groundwater at an average rate of 416 lit/s. The groundwater is rich in hydrogen sulfide (H2S) gas. The gas reacts with the tunnel humidity and produces an acidic fume that penetrates the tunnel lining and decomposes its concrete and steel reinforcement, as well. The exact locations of these discharging conduits and their morphology are not known, since the TBM segmental lining conceals them. An elaborate post-grouting plan is on the drawing board to reclaim the aquifer but the cost of a systematic grouting is particularly high and at best scenario not conclusive. The scope of this paper is to discuss a series of carefully controlled field experiments in a 100m pilot study area along the tunnel. It manipulates on the TBM performance parameters that were registered during the tunnel excavation stage. Based on this information, suitable field models are established that may be interpreted as being associated with either water or air-filled solution channels and open joints. The results are supported by in-situ permeability tests, where the suspected joints were theatrically identified and were cement grouted after construction phase. Introduction Zagros water conveyance tunnel in Kermanshah province of Iran is near the town of Pole Zahab. This part of the project is regarded as the second lot of a broader plan, which is schemed approx. 26 km long and is 6.73m in diameter. It has been under construction using a Herrenknecht hard rock double-shield TBM since March 2005. So far, 15 km (58%) of this tunnel has been completed. In the course of tunnelling, the machine encountered nearly many extraordinary situations related to high groundwater and H2S gas intrusion, all of which resulted in a significant reduction in TBM utilization rate and an increase in construction delays, as well as excavation costs. The water seepage in low amounts was first experienced at TM 3700. A significant water ingress in the range of Q>110 lit/s was later intruded at TM 4157, which rapidly accumulated to Q~315 lit/s with further advancement to TM 4435. Advancing deeper into the core of aquifer at TM 8256, the accumulative water seepage totaled Q~730 lit/s, with further advancement to TM 13846, one hundred fifty five more liters of gas bearing water seeped into the tunnel, totaling the tunnel discharge flow at the portal outlet to 900 lit/s. This amount of water released 700 ppm hydrogen sulfide gas into tunnel atmosphere. Figure 1 shows the water discharge rate and the H2S gas concentration at the pilot study area where is marked as Ezgelleh Anticline on the graph. One of the major factors affecting the performance of tunnel boring machines is the degree of fracturing of the rock. During excavation, machine performance parameters are continuously displayed and recorded on the control cabin monitors. Figure 2 shows the TBM display screens. The screens display TBM performance parameters and register TBM mechanical behavior against the excavated material. These screens disclose an assorted set of data; e.g., penetration rate, boring time, total thrust, torque power, cutter speed etc… Based on the careful analysis of these parameters, uniform patterns were established as a model to identify concealed joints and to delineate water-carrying conduits along the tunnel path. The objective is to employ a model to locate water conduits and fill in the leaks and cracks by post-curtain-grouting. This is in contrast to a systematic grouting approach where grouting is done in a continuum fan pattern.
- Research Report > Strength High (0.54)
- Research Report > Experimental Study (0.54)
- Geology > Geological Subdiscipline (0.95)
- Geology > Rock Type (0.68)
- Geology > Structural Geology > Tectonics > Compressional Tectonics > Fold and Thrust Belt (0.36)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Corrosion inhibition and management (including H2S and CO2) (1.00)
- Health, Safety, Environment & Sustainability > Health > Noise, chemicals, and other workplace hazards (1.00)
Abstract The present papers deals with in situ characterization of rock formations as per Schmidt Rebound Hammer classification values (R) and portrays a model for spatial susceptibility of landslides in mountainous terrain. A geotechnical classification of rock masses depending on the range of R-value has been proposed and a regional correlation with the structural features traversing in the area has been attempted. Rebound values have been utilized to estimate the geo-mechanical properties of in situ rock to categorize the different lithological assemblages into geotechnical units of varying competencies. Geotechnical units assigned weightings of slope parameters, structure and bedding relations, land use and land cover etc and the terrain has been categorized into susceptibility classes such as very low, low, moderate, high and very high depending on the spatial probability of landslide occurrence highlighting relative severity of landslide hazard. Introduction Rock mass characterization offer many geotechnical challenges as the rock behaves in many different ways in its natural geological environment owing to inherent lithological and structural variations. At times these inherent characters are alone not sufficient to understand the behavior of rock mass under loading and excavations for major civil engineering structures. In an attempt to provide guidance on the properties of rock masses a number of rock mass classification systems have been developed. The most widely known classifications are the RMR system of Bieniawski (1973, 1989) and the Q system of Barton, Lien and Lunde (1974) etc. The classifications include information on the strength of the rock material, the spacing, number and surface properties of the structural discontinuities as well as allowances for the influence of subsurface water, in situ stresses and the orientation and inclination of dominant discontinuities. The strength parameters used are invariably the laboratory tests done on the rock samples which may not represent in situ strength of the rock mass. The present paper deals with characterization of rock formations according to the Schmidt rebound hammer classification values (R) which have been used in rock mass characterization. Rebound values have been utilized to estimate the geo-mechanical properties of in-situ rock to categorize the different lithological assemblages into Geotechnical Units of varying competencies. A case of such geotechnical classification has been attempted in parts of Kali River valleys of Eastern Kumaun Himalaya in order to portray a model of spatial susceptibility of landslides. The likelihood of landslides in such hilly terrains exposing the bedrock along their slopes is, largely dependent on the strength of the rock mass besides other factors that are known to govern the occurrences of landslides.
- Geology > Rock Type (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Abstract Structural geology (a branch of geology aiming at describing the structures – joints, faults, folds, etc. – at various scales) can be used in the field of rock mechanics and rock engineering, and particularly in underground engineering works (tunnelling and rock caverns) to gather more reliable data for empirical stability analyses and deterministic calculation models. Methods of structural geology are presented and their applications in rock mechanics/rock engineering are highlighted in particular through the observation of faults and joints arrest. Structural geology allows a better understanding of the origin, the chronology and the mechanical behaviour of discontinuities, and therefore a more accurate rock mass characterization and rock mass classification, as well as a validation of the actual stress regime. Examples selected from different countries of using structural models are also given with emphasize on the necessity and the way to build a 3D model at each stage of an underground project, from site selection to investigation and construction, to ensure the quality and validity of rock mechanical data and assumptions. Introduction In the last five years, several publications and oral presentations insisted on the importance of structural geology in the field of rock mechanics (e.g. during Sinorock 2009 in Hong Kong or the ISRM congress in Beijing in 2011). They highlighted the necessity of using structural geology and structural data as input parameters for rock mass characterization and rock mass modelling. This wish is praiseworthy and corresponds to a real need. The situation is due to the lack of structural geologists on the market: structural geology being less taught in university and often replaced by engineering geology, geologists or engineering geologists are easily involved in big projects (e.g. dams, hydropower plants, tunnelling, etc.) whereas it is nowadays quite uncommon to meet structural geologists in teams in charge of design, modelling or even supervision of site works. In addition, most structural geologists are academics and very few are full-time practitioners, especially in the field of rock mechanics. This short paper cannot be exhaustive but set out the various possibilities offered by structural geology. The objective is less ambitious and is limited to the presentation of practical examples in different geological situations in which a structural knowledge can provide a real help for modelling or for characterizing the rock mass through the two most geology-based rock mass classifications, the Q system (Barton et al. 1974) and the RMR (Bieniawski 1989). Since the vocabulary also acts as a brake, this paper deliberately uses simplified technical vocabulary and concepts, hoping that this will bring rock mechanical engineers to working closer with structural geologists.
- Geology > Structural Geology (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
Abstract The laboratory results of axial compression test with different angle between loading direction and normal direction of bedding plane are introduced. Due to the high density of bedding plane in the schist, the test result show a significant anisotropic in uniaxial compressive strength and Young's Module. The results of strength and Young's Module when bedding plane is horizontal are larger than the test results of any other bedding plane angle. It's difficult to simulation the anisotropic strength and deformation response during the compression test with constitutive model. The bonded particle model and smooth-joint model in PFC (Flow Particle code) was used to mimic schist. The rock host of schist was simulated by parallel-bonded particle, and the high density bedding plane was simulated by smooth-joint model. Axial compression tests with different load angle was simulated, a good agreement was observed between experiment results and simulation results. Introduction In general, the most anisotropic elastic behaviour of material is described by 21 independent elastic constants. The orthotropic isotropic reduce the independent elastic constants from 21 to 9, and the transversely isotropic model is characterized by 5 independent elastic constants. Transversely model is the most popular model for schistose rock like schist, gneiss, shale, etc. In order to determined 5 independent elastic constants, at least 3 specimens that bedding plane inclined parallel, vertical, and at an angle are required. Previous research has established ways to minimize the laborious task of preparing multiple specimens, one approach is to reduce the 5 independent elastic constants to four by using Saint-Venant's empirical equations for shear modulus in the plane normal to the isotropic plane. These empirical equation is not acceptable for schistose rock. Although significant achievements have been achieved over the past 40 years, there is no standard method has been suggested to determine the elastic constants of schistose rock. In this paper, we firstly introduce the experiment study of a typical schistose rock: Danba schist, then calculating the 5 independent elastic constants of Danba schist based on experiment results. The main objection of this study is to simulation the uniaxial compressive test by using PFC and compare the simulated results with laboratory test result and analytical results.
Research on Stress State in Slopes Subjected to Tectonic Stress During Valley Incision by Geomechanical Modelling
Su, Shengrui (Department of Geological Engineering, Changan University) | Li, Peng (Department of Geological Engineering, Changan University) | Wang, Qi (Department of Geological Engineering, Changan University) | Wang, Xiaojian (Department of Geological Engineering, Changan University)
Abstract Taking the Longmenshan complex geological environment as the study background, a geomechanical model with a reverse fault and subjected to horizontal tectonic stress is built and valley incision process is modeled. After excavation, the right slope has the contrary dip to faults but on the left slope the dip is similar to faults. Valley side slope presents tensile stress and the valley floor presents compressive stress. During valley incision the right slope display tensile stress state and its stress distribution show different characteristics of zonation from surface to inside of the slopes. As the valley incision depth increases, the position of tensile stress concentration area in right slope has changed from inside to surface, and lastly to the top of overlying fault. Stress state of left slope is complex and mainly performs tensile stress, but it also shows different characteristics in upper and lower slope. Introduction The crustal stress refers to all stress distributed in the earth, which is a stable field in macroscopic and perform variety at one point with the time changing, namely, it is a function of the time and space (Su et al., 2002). When the concept of crustal stress was defined by A. Heim in 1912, it has become a focus to geologists all over the world and gotten a large number of acheivements (Cai et al., 1995; Lee et al., 1996). The stress state of a slope adjusts continously with geological environment changing and determines it's deformation and failure mode, therefore, systematically and accurately grasping stress distribution characteristics have a great significance to slope stability evaluation and protection (Tang, 2011). Valley stress is a special stress field which is influced by regional tectonic stress and formed by stress adjusting in valley floor and valley side slopes along with river incised process (Tian et al., 2002). There are plentiful hydropower resources in China, especially in the alpine valleys of southwest China. Since valley incision has brought a series engineering geological problems, the distribution of valley stress field gets more and more attention in recent years. Zheng Xiaoyan (2012) and TianYuzhong (2002) discussed the characteristic of valley stress by numerical simulation. In recent years, a large number of measured data have been accumulated in water conservancy projects in southwest China (Zheng et al., 2012; Bai et al., 1982; Huang et al., 1996) and provided reference basis for valley stress field study. Studying valley stress field, especially the stress distribution of valley slope which is influenced by tectonic stress has great significance. Current research techniques are mostly limited to the numerical simulation. Although there are a large number of measured data, its research scope is limited and both of them cannot reflect the real stress state in the slopes. Therefore, the geomechanical simulation experiment of the valley excavation to reseaching the valley stress distribution is necessary.
- Geology > Structural Geology > Tectonics > Plate Tectonics > Earthquake (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Asia > China > Sichuan > Sichuan Basin (0.99)
- Europe > United Kingdom > England > London Basin (0.91)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
Stability Analysis for to ppling Failure of Unstable Rock in Three Gorges Reservoir Area, China
Wang, G. L. (Xi’an Center of Geological Survey, China Geological Survey) | Wu, F. Q. (Institute of Geology and Geophysics, Chinese Academy of Sciences) | Ye, W. J. (Xi’an University of Science and Technology)
Abstract As distinguished from the former types of toppling failure (i.e. flexural, blocky, blocky-flexural and secondary), another type of toppling failure developed in interbedded hard rock and soft rock slope is very common in Three Gorges Reservoir region. Based on discrete element method, the failure process of toppling failure can be summarized as erosion notches → tension cracks → toppling failure → gravitational transport and accumulation. According to the toppling failure mode, the computing formula of factor of safety is deduced by means of the method of geo-mechanics. The results of a typical case study show that the factor of safety of toppling failure decreases with increasing of notch depth. Supposing the erosion rate of notches is 1 mm/yr and toppling failure of the unstable rock occurs at a notch depth of 1.45 m, we can calculate the time required for the unstable rock to topple as 50 years. Introduction Toppling failure is one of the most serious and hazardous instability of rock slopes (de Freitras and Watters 1973; Goodman and Bray 1976; Wang 1981; Ishida et al. 1987; Goodman 1989; Aydan and Kawamoto 1987, 1992; Adhikary et al. 1996, 1997, 2007). Many toppling failures are observed in practice and hence toppling is an important failure mode that requires further attention (Wyllie 1980; Liu et al. 2010). In general, this failure can be classified into four principal types: flexural, blocky, blocky-flexural and secondary (Goodman and Bray 1976). Flexural toppling failure occurs due to bending stresses (Amini et al. 2009). However, another mode of toppling failure, which mainly developed in interbedded hard rock (i.e. sandstone) and soft rock (i.e. mudstone, shale and limestone) slope is very common in Three Gorges Reservoir region (Chen et al. 2004; Dong et al. 2010). Field investigation indicates that notches of undercut slopes are formed by differential weathering. Furthermore, tension crack on the top surface will occur due to concentration of tensile stress. As result, the unstable rock begins to topple because of momentum unbalance.
- Asia > China (0.69)
- North America > United States (0.46)
Abstract A critical aspect of rock engineering modelling and rock engineering design is ensuring that all the necessary variables have been included and that the interactions between them are understood—but this is not easy to establish without a guiding methodology. For this reason, the author developed the Rock Engineering Systems (RES) approach in 1992 and, in the 20+ years since then, the RES approach has been used for a wide variety of rock engineering and other problems. As a result, there are now many case studies available which illustrate the application of RES to rock engineering problems. In this paper, the basic RES methodology is outlined and 34 case examples are referenced. The diversity of these 34 case examples illustrates the variety of applications and approaches used by different researchers and practitioners. The link between RES and ‘intelligent’ methods is emphasised. Introduction When designing a project to be constructed on or within a rock mass for either a civil or mining engineering purpose, it is essential to have sufficient knowledge to ensure the safety of the construction and the succeeding use of the facility. In order to reduce the attendant risk to an acceptable level, it is necessary to consider the associated epistemic and aleatory uncertainties—remembering that epistemic uncertainty is concerned with lack of knowledge about a process or model, and aleatory uncertainty is concerned with the inherent randomness of a process or model. In this paper, we review how epistemic uncertainty can be significantly reduced by the use of Rock Engineering Systems (RES) originally developed by Hudson (1992). In the following sections, the RES approach is summarised, including the interaction matrix and coding the matrix according to the significance of the interactions between the variables, together with the associated ‘Cause-Effect’ plot. Key case example applications that have been published over the last twenty years are listed via a table of the main variables used for each application. These case examples represent studies from Bangladesh, China, Greece, Iran, Italy, Korea, Spain, Sweden, Turkey, UK, and the USA.
- Europe (1.00)
- Asia > China (0.68)
- Asia > Middle East > Turkey (0.34)
- Asia > Middle East > Iran (0.25)
- Geology > Rock Type (0.95)
- Geology > Geological Subdiscipline > Geomechanics (0.71)
- Energy > Power Industry (0.68)
- Materials > Metals & Mining (0.48)
- Health, Safety, Environment & Sustainability > Environment (0.95)
- Data Science & Engineering Analytics > Information Management and Systems (0.90)
- Reservoir Description and Dynamics > Reservoir Characterization > Reservoir geomechanics (0.71)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (0.48)
Discrete Element Analysis of the Effect of Meso-Structure Heterogeneity on the Mechanical Behavior of Rock
Liu, Tian-wei (State Key Laboratory of Hydroscience and Engineering, Tsinghua University) | Xu, Wen-jie (State Key Laboratory of Hydroscience and Engineering, Tsinghua University) | Zhang, Hai-yang (State Key Laboratory of Hydroscience and Engineering, Tsinghua University) | Lv, Chao (Department of Civil Engineering, Tsinghua University)
Abstract The effect of meso-structure heterogeneity in material on the mechanical behavior of rock is studied in this paper, using Discrete Element Method and Weibull distribution model. Several triaxial compressive tests are conducted. Different meso-structure distributions are used. It is shownby numerical tests that the different internal meso-structure distribution can have considerable effects on the compressive strength, crack initiation stress and stress-strain relationship, and other macro-properties. The micromechanical behavior of rock samples is affected by the distribution of internal meso-structure parameters as well. The deformation and failure of rock is simulated by tracing the extension of the microscopic cracks and the micromechanical behaviors. Results demonstrate that the meso-structure heterogeneity have considerable effects on the mechanical behavior of rock. Instruction The constitutive relation of rock has always been the focus of geotechnical research, with many kinds of models being found. However, most of the existing models cannot reflect the real behavior of rock in the force-deformation process actually. Rock and soil under complex geological conditions often exist in deep rock mass with high stress, so that their mechanical deformation properties are often non-linear, ductility and nonuniform. The modeling and application of discrete element method in geotechnical engineering have undergone a relatively mature development, since itwas initiatively proposed by Cundal (1971). The discrete element modeling method is widely used in establishing models to trace the emergence and development of the microscopic cracks, estimate the ultimate strength, predict the body changes during force deformation process and so on. Many international scholars have researched the application of the discrete element method in geotechnical engineering. Cho N, Martin CD et al (2007) explored the influence of the clustering characteristics for particles of rock and soil on the deformation and failure of corresponding materials. Diederich MS (2000) did research into the instability of hard rock specimens in tensile failure. Griebel M, Knapek S et al (2007) adopted numerical simulation and comparison to study the particle settings, algorithm selections and application of parallel computing in the calculation of dynamic characteristics for particle materials. Hazzard JF, Young RP (2000) modeled the mechanical properties of meso-structure to research its deformation and failure characteristics. Hoek E, Brown ET (1998) did some practical simulations and estimates on the strength of the rock specimen. Kazerani T, Zhao J (2010) fitted the failure of brittle materials using the method of bonding particles, compared and analyzed the influence of different meso-structure parameters on the deformation and failure of brittle materials. Jing L, Stephansson O(2007) systematically proposed basic principles of the theory and application of the discrete element model in geotechnical engineering.
- Research Report > New Finding (0.34)
- Research Report > Experimental Study (0.34)