**Current Filters**

**Source**

**SPE Disciplines**

**Theme**

**Author**

- Backers, T. (1)
- Bang, S.H. (1)
- Cai, M.F. (1)
- Chen, B.R. (1)
- Cui, Y. (1)
- El-Omla, Mohamed (1)
- Fahimifar, Ahmad (1)
- Feng, X. (1)
- Feng, X.T. (1)
- Grossauer, K. (2)
- Guanye, Wu (1)
- Hongyun, Ren (1)
- Huang, S.L. (2)
- Huifeng, Zheng (1)
- Jeon, S. (1)
- Ji-Liang, Zhu (1)
- Jiaqing, Shu (1)
- Jing, Lanru (1)
- Jixun, Zhang (1)
- Ke, D. (1)
- Lan, Hengxing (1)
- Li, L.C. (1)
- Li, Shouju (1)
- Li, X. (1)
- Liu, Y.M. (1)
- Liu, Yingxi (1)
- Luo, H.Y. (1)
- Martin , C. Derek (1)
- Meier, T. (1)
- Osgoui, Reza R. (1)
- Radonc;Ic, Nedim (1)
- Schuber, Wulf (1)
- Schubert, W. (2)
- Shenghong, Chen (1)
- Shi, L. (1)
- Stephansson, O. (1)
- Su, Guoshao (1)
- Tang, C.A. (1)
- Tong, Fuguo (1)
- Vakilzadeh, Arash (1)
- Wang, J. (1)
- Wu, Fengji (1)
- Xian-Ting, Chen (1)
- Xu, D. (1)
- Xu, T. (1)
- Xuhua, Ren (1)
- Zhao, J. (1)
- Zhou, W. (1)
- Zimmerman, Robert W. (1)

**Concept Tag**

- algorithm (1)
- alteration (1)
- alteration mineral (1)
- analogical reasoning (1)
- analysis (5)
- aperture (1)
- application (1)
- approach (1)
- Artificial Intelligence (5)
- backfill (1)
- Behavior (4)
- behaviour (1)
- Beishan area (1)
- benchmarking (2)
- bentonite (2)
- biotite (1)
- block (1)
- block element (1)
- buffer (2)
- cavern (2)
- China (1)
- Chinese (1)
- condition (5)
- crack (2)
- deformation (6)
- DEM (1)
- design (2)
- DFN (1)
- displacement (5)
- Displacement Mag (1)
- Disposal (1)
- distribution (4)
- element (5)
- Engineering (2)
- equation (2)
- evolution (3)
- excavation (3)
- failure (4)
- Feldspar (1)
- Figure (9)
- flow in porous media (2)
- Fluid Dynamics (2)
- fracture (2)
- function (2)
- Gaussian process (1)
- geologic modeling (2)
- geomechanics (3)
- GP model (1)
- Heshang Tunnel (1)
- Influence (1)
- Itasca Consulting Group (1)
- Landslide Hazard Zonation (1)
- LiDAR (1)
- Linestyle (1)
- lining (3)
- machine learning (2)
- material (3)
- Maximum (1)
- measurement (2)
- method (5)
- Minneapolis (1)
- model (7)
- MPa (1)
- operational safety (2)
- optimization problem (3)
- parameter (4)
- Penzien (1)
- permeability (2)
- plane (2)
- pressure (3)
- process (2)
- property (2)
- reservoir simulation (11)
- Response (1)
- result (2)
- rock (12)
- rock mass (4)
- Rock mechanics (1)
- section (2)
- Simulation (1)
- slope (2)
- solution (3)
- stability (3)
- stage (2)
- strain (2)
- strategic planning and management (2)
- strength (4)
- stress (8)
- support (3)
- temperature (3)
- Thickness (1)
- THM (1)
- time (2)
- Trend (1)
- tunnel (8)
- velocity (2)
- Wang (1)
- water (2)
- wellbore integrity (3)
- zone (2)

**Industry**

**Oilfield Places**

**Technology**

**File Type**

Presently the survey of absolute displacements of targets fixed at the tunnel wall is the state of the art in performance monitoring of tunnels. Monitoring data are used to assess the stabilization process of the tunnel, more recently also for the short term prediction of the ground conditions ahead of the face.

The displacements do not substantially vary in rock mass conditions with nearly constant properties and influencing factors. On the other hand, changes in the rock mass structure or properties result in changes in the displacement characteristics.

For nearly constant conditions, the displacement trends show minor fluctuations within a certain normal range, due to minor variations in the rock mass properties. Deviations from this range are clear indicators for changing conditions ahead of the face or outside of the tunnel. To identify such trend deviations the normal range of the trend lines becomes crucial. Geostatistical methods allow an automatic identification of trends along the tunnel. Using data from completed tunnel projects a “reference trend table” can be established. By comparing actual observed trend characteristics to this reference table changing ground conditions ahead of the face can be identified and hence, the change in the displacement characteristics and magnitudes can be predicted.

During construction the measurement results contain all influences of the ground structure, stresses, and interaction between ground and support. The previously established characteristic behaviors for certain conditions are compared to the monitoring results. In case of agreement it can be established that the observed behavior is “normal”. Deviations from the expected behavior can have various reasons. One may be that the behavior during design was not assessed correctly. In this case, a refinement of the model is required. Another reason for behavior deviating from the expected can be a change in the ground conditions ahead of the face. It is meanwhile well known that trends of displacement vector orientations can be used to predict changing ground conditions ahead of the face (Schubert & Budil 1995, Steindorfer 1997, Jeon et al. 2005).

ISRM-SINOROCK-2009-144

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

Oilfield Places: North America > United States > Alaska > North Slope > Western North Slope > Alpine Oil Field (0.97)

SPE Disciplines:

It is very difficult to predict accurately non-linear deformation time series of surrounding rock using general methods expecially under complex geological condition. A new method based on Gaussian Process (GP) machine learning, which is a newly developing machine learning method with excellent capability for solving highly nonlinear problems with small samples, is proposed. The method was verified by modeling deformations of surrounding rock of Yangzong tunnel in Yunnan Province, China. The monitoring nonlinear deformation time series of surrounding rock during excavation are taken as learning samples for GP machine learning. Non-linear relation of the deformation time series can be obtained by learning process of GP. Then, the future nonlinear deformations are predicted by using time series analysis based on GP. The results indicate that GP can appropriately describe the evolutionary law of non-linear deformation of tunnel and provide accuracy predictions. Furthermore, the results also show that the method is feasible, effective and simple to implement.

Gaussian process (GP) is a newly developed machine learning technology (Rasmussen and Williams, 2006) based on strict theoretical fundamentals and Bayesian theory. In recent years, GP has attracted much attention in the machine learning community, there are a lot of successful applications in the field of solving for nonlinear, small samples and high dimensions problems (Seeger, 2004; Girolami, 2006; Gramacy, 2007). GP is moderately simple to implement and use without loss of performance compared with ANN and SVM (Xiong, 2005).

In this paper, a new model based on GP is proposed to model and predict non-linear deformation time series of surround rock of tunnel. The model is verified by its application to study non-linear deformation time series of Yangzong Tunnel in China.

ISRM-SINOROCK-2009-109

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

SPE Disciplines: Management and Information > Information Management and Systems > Artificial intelligence (1.00)

Technology:

- IT > AI > Machine Learning > Statistical Learning (1.00)
- IT > AI > Representation & Reasoning > Uncertainty > Bayesian Inference (0.87)

This paper presents a new FEM approach and computer code for modeling fully coupled thermo-hydro- mechanical processes associated with underground nuclear waste repositories. The governing equations are based on the theory of mixtures applied to the multiphysics of porous media, considering solid-phase deformation, liquid-phase flow, gas flow, heat transport, thermally-induced water flow, phase change of water, and swelling deformation in buffer materials. For three-dimensional problems, three displacement components, water pressure, gas pressure, vapor pressure and porosity are chosen as the eight primary variables. The code was tested against a benchmark test that was performed in laboratory conditions on vertical cylindrical columns of compacted MX-80 bentonite by the French Commission of Atomic Energy from 2003 to 2004. The comparison with the benchmark tests shows good agreement between the numerical predictions and the measured data, thus providing a partial validation of our new code. Discussion of outstanding issues and conclusions are presented at the end of the paper.

In the field of geological disposal of radioactive wastes, many coupled THM numerical models have been developed (Olivella, 1994; Börgesson, 1996; Nguyen, 1996; Noorishad, 1996; Ohnishi, 1996; Thomas, 1996). Some of them have the capability to model liquid flow in unsaturated media through the use of the Richards equation (Richards, 1931), but the gas phase movement is usually ignored using the assumption of a constant and small gas pressure. Although some THM numerical models and codes can simulate two-phase (gas and liquid) fluid flow with two components (air and water) in partially saturated soil, coupled with heat transport and mechanical responses (Rutqvist, 2001), they usually neglect the advective flow of vapor and cannot consider the transfer of heat between the phases. By making the assumption of spontaneous thermo-dynamic equilibrium between the soil liquid and the water vapor, the vapor pressure becomes a variable that depends on suction and temperature, and the flux of vapor and liquid water can be modelled using a single equation (Khalili, 2001).

In order to increase the capability of modeling coupled THM processes in buffer and rock-buffer interfaces, a fully coupled THM numerical model, along with a computational FEM code ROLG, are developed and presented in this paper. In this model, the gas flow and the vapor flow are described by their mass conservation equations, and moisture movement and phase changes are considered. The developed numerical model and code are verified through a laboratory benchmark test as part of Work Package 4 of the EC sponsored project THERESA.

ISRM-SINOROCK-2009-112

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

benchmarking, bentonite, buffer, change, coefficient, deformation, equation, flow in porous media, Fluid Dynamics, formation evaluation, gas, gas pressure, material, model, multiphase flow, permeability, porosity, pressure, production control, production monitoring, reservoir simulation, result, strategic planning and management, temperature, vapor, vapor pressure, water

SPE Disciplines:

When dealing with tunnels in weak rock mass and with high overburden, the high displacements imposed on the lining dictate the application of ductile yielding elements with controllable stiffness and yield load. These properties are chosen with two goals in mind: the time-dependent strength of the shotcrete shell must not be exceeded; however the support pressure must be kept reasonably high and controllable. The attainable load-displacement lines of the ductile support elements are almost arbitrary. There are almost countless possible combinations of their stiffness and yield load, thus enabling the development of custom-tailored support systems and leaving considerable room for adapting to the encountered ground conditions. Tunneling in weak ground should be accompanied by increased efforts on monitoring the system behavior, best by a dense pattern of absolute displacement measurements. A simple technique for calculating the shotcrete utilization ratio has been developed. It applies a Newton- Raphson root-finding algorithm to determine the interpolation parameters while obeying the requirements of force equilibrium and fitting the measured displacements. The influence of non- symmetrical displacement behavior caused by heterogeneity and anisotropy of the rock mass, on the lining loading can be quantified and used for support system optimization.**1. INTRODUCTION**High primary stresses associated with tectonic faulting frequently create problems during construction of Alpine base tunnels. Keeping the displacements in a range which could be sustained by the support would lead to economically unfeasible lining thickness.

Ductile lining systems using in mining cannot be be transferred to traffic tunnels with their requirement of long term stability. First concepts of yielding supports for tunnels date back to the nineteen fifties (Rabcewicz 1950).

The technical requirements posed on a ductile support system are quite clear:

- The load-displacement characteristics should be “steerable” within a broad range, allowing the avoidance of overstressing the shotcrete shell, while enabling easy modifications in order to cope with the ground heterogeneity and usually long-lasting displacement increments.
- The support resistance has to be reasonably high, allowing a certain amount of control over the displacement magnitude.

(Figure in full paper)

ISRM-SINOROCK-2009-162

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

SPE Disciplines:

An excavation slope in left abutment trough of Xiluodu arch dam has 380 meters or so. In order to ensure safety of the excavation slope, the designed excavation and reinforcement process of the slope is simulated systematically with self-developed 3D elasto-viscoplastic finite element method (FEM) analysis program based on the model of reinforced jointed rock masses. Distribution patterns of displacements, stresses and point safety factors of the rock slope and reinforcement effects under tectonic initial geostress field are analyzed and the slope stability is evaluated in each excavation step. The simulation results show that displacements of the excavated slope between 470 meter and 400 meter in elevation are relatively bigger and its yield zone extends deeper into the mountain body in the designed excavation and reinforcement scheme. Supplementary reinforcements with some pre-stress cables are suggested for strengthening the excavation slope from 470 meter to 400 meter in elevation. The numerical simulation results show that the new reinforcements help improve the stability of the excavation slope in left abutment trough and ensure the safety of the slope.

In order to ensure the stability and safety of the excavation slope, many supports should be utilized to reinforce the slope in a construction period, which are pre-stress cables, pre-stress bolts, systematic bolts, etc.. Which position should be reinforced, and how many bolts and cables should be adopted are focuses of engineering design and construction. Unsuitable reinforcement measures and reinforced locations will not prevent slope from instability effectively and only increase engineering investments. Consequently it has a great significance to study excavation slope stability and reinforced effects of corresponding reinforcement measures with computer aided simulation technologies before the slope excavation (FENG Xue-min, WANG Wei-ming, et al., 2004)

Finite element method has gained popularity in analyzing geotechnical problems for fewer assumptions and more powerful functions (Chen, S.H., Egger, P.,1999; Chen Sheng-hong, Qing Wei-xin, Shahrour Isam, 2007).The excavation and reinforcement process of rock slope can be simulated conveniently by finite element method with suitable constitutive models of geomaterials.

ISRM-SINOROCK-2009-101

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

SPE Disciplines:

A numerical model based on time-dependent degradation law was applied in the paper to simulate thetime-dependentdamageand deformationofrock materialsunderconstantstresslevels. An empiricalrelationbetweendegradationofmaterialpropertiesandappliedstressisusedto simulatethe mechanical behavior of each elementoffinite element model. The time-dependent degradationlawofmaterialisusedatthescaleofeachelementtosimulateitsdamage.In modeling, an element is damaged by decreasing its Young’s modulus or strength to simulate the effectoflocaldamageatmicroscopicscales.Elasticinteractionsbetweenelementsand heterogeneity of material properties lead to the emergence of a complex macroscopic behavior. In particular, the primary and tertiary creep regimes associated respectively with a degradation and increase of the rate of strain, damage event and energy release were observed in the simulations. Damage localization emerges at the transition between primary and tertiary creep, when damage rate starts accelerating. This model can reproduce the three creep regimes and associated damage evolutionofrock,whichisofgreathelptoinvestigatetime-dependentinstabilityfailure mechanisms of rock mass and to prevent associated rock hazards in rock engineering.

Threeregimesareusuallyobservedduringcreep experiments: primary creep or transient creep (decreasing strainrate),secondarycreeporsteady-statecreep (constant strain rate), and, for large enough stress, tertiary creeporacceleratingcreep(increasingstrainrate), endingbyfailure(Lockner,1993a;Boukharovetal., 1995; Chen et al, 1997). During primary creep, the strain rateusuallydecreasesasapowerlawofthetimesince thestresschange.Thisexperimentallawwasfirst observedfor metalsandthenfor manyother materials, suchasrocks(Lockner,1993b).Thestrainrateduring secondary creep is nearly constant, and strongly depends on the applied stress. A power law acceleration of strain ratehasbeenrevealedduringtertiarycreep(Voight, 1989).Thethreeregimesdevelopinparallelandtoa certain extent independently.

Laboratory tests and in-situ rheological observations are the major methods employed to study time-dependent behavioranddeformationrulesofrockmaterials.

ISRM-SINOROCK-2009-065

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

SPE Disciplines:

Liu, Y.M. (Beijing Research Institute of Uranium Geology) | Wang, J. (Beijing Research Institute of Uranium Geology) | Ke, D. (Beijing Research Institute of Uranium Geology) | Cai, M.F. (University of Science and Technology Beijing)

In order to safely dispose of the high-level radioactive waste (HLW), R&D guide of HLW disposal was published in February 2006 in China. The spent fuel from nuclear power plants will be reprocessed first, followed by vetrification and final disposal. A conceptual repository 3D configuration comprises a single vertical borehole in a continuous and homogeneous hard rock, containing a canister surrounded by an over-pack and a bentonite layer, and the backfilled upper portion of the gallery using FLAC3D. To take into account in situ stress, geothermal gradient and groundwater of Beishan area, thermal relief of HLW and swelling pressure of buffer/ backfill material made by GMZ01 bentonite, the TM, HM and THM evolution of the whole configuration is simulated over a period of 100 years. The results demonstrate that temperature is hardly affected by the couplings. In contrast, the influence of the couplings on the mechanical stresses is considerable. The repository has long-term stability in fully THM coupling action condition.

China commenced its deep geological disposal of HLW programme in 1985 when a Coordination Expert Group for the HLW Geological Disposal was established under China National Nuclear Corporation. R&D guide of HLW disposal was published in February 2006 (CAEA 2006). The spent fuel from nuclear power plants will be reprocessed first, followed by vetrification and final disposal. The preliminary concept of geological disposal of HLW will be a shaft-tunnel model based on a multi-barrier system, located in saturated zones in granite. It takes the preselected Beishan area located in Gansu province as the research background and GMZ01 bentonite as the buffer material.

Heat generated from the waste in the repository will result in an increase in rock temperature and the rock mass tends to expand. Chan and Reid (1987) developed a three dimensional finite-element code, MOTIF (Model Of Transport In Fractured/porous media) to model the coupled processes of groundwater flow, heat transport, brine transport, and one-species radionuclide transport in geological media of Canadian Shield. Lee (Lee 1994) evaluated the thermo-mechanical stability of a rock mass around a nuclear fuel waste disposal vault which is to be located in a granitic pluton in the Canadian Shield based on computational methods and field observations. Hudson et al. reviewed coupled T-H-M issues relating to radioactive waste repository design and performance (Hudson 2001).

ISRM-SINOROCK-2009-183

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

Oilfield Places:

- Asia > China > Gansu > Beishan Basin (0.98)
- Asia > China > Gansu Province (0.91)

SPE Disciplines:

This paper presents GIS-based deterministic approaches for earthquake-induced landslide hazard evaluation and zonation. These approaches combine numerical slope stability analysis with GIS spatial analysis to evaluate earthquake-included slope failures, both shallow and deep-seated. The study focuses on GIS-based procedure of landslide hazard zonation, which involves one-, two-, and three-dimensional deterministic methods. The conventional slope stability analysis methods such as the widely used limit equilibrium methods in geotechnical engineering including block sliding model, methods of slices, and Hovland’s column method were incorporated into the GIS- based procedure.

This paper also discussed causative factors analysis of earthquake-included landslide hazards including the determination of peak ground acceleration, evaluation of the topographic effect of ground motion, and the seismic response analyses. The developed approach was applied to a specific site in the Balsamo Ridge area next to the city of Nueva San Salvador, E1 Salvador. The study demonstrated that the zonation map produced using the 2D and 3D methods has achieved such a level of accuracy that can be used for engineering design and decision-making in land use development.

Although earthquakes can hardly be predicted, the susceptibility to earthquake-induced landslides of area can be assessed on the basis of potential ground motion, geological, and geomorphologic conditions.

During last two decades, research has proven that GIS (Geographic Information Systems) provides a powerful tool for landslide hazard zonation. However, seismic- induced landslide susceptibility assessment inherits complex uncertainties of terrain, seismic, and geotechnical parameters. For deterministic analysis models such as the infinite slope model is only applicable for shallow slope sliding prediction. In fact, circular slope failure and deep slope sliding occur more commonly than otherwise in earthquake prone areas and these types of landslides usually are the major cause of property damage and fatalities. It is essential to develop a reliable analysis model that considers failure modes, geotechnical parameters, and uncertainties to achieve the accuracy needed for seismic-included landslide hazard evaluation and zonation.

This paper presents a newly developed GIS-based deterministic approach for earthquake-induced landslide hazard evaluation and zonation. This approach combines numerical slope stability analysis with GIS spatial analysis to evaluate earthquake –induced slopes failures. The scopes of the study focused on the GIS-based procedure of landslide hazard zonation, the evaluation of peak ground acceleration, and the topographic effect of ground motion. The widely used limit equilibrium methods in geotechnical engineering including one-dimensional (1D) block sliding model, two-dimensional (2D) methods of slices, and three- dimensional (3D) Hovland ‘s column methods were in corporate into this GIS-based procedure.

The slope stability was calculated using customized programs combine VBA (Visual Basic for Applications) with GIS grid- based spatial analysis.

ISRM-SINOROCK-2009-176

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

Ji-Liang, Zhu (Guangxi Electric Power Industry Investigation Design and Research Institute, Nanning) | Xian-Ting, Chen (Guangxi Electric Power Industry Investigation Design and Research Institute, Nanning)

Based on the simplified structure of rock mass, FLAC3D numerical modeling technique is used to systematically analyze the distribution features of the secondary stress field, strain field and plastic zones in the surrounding rock mass of the underground cavities after the excavation. And the variation characteristics of stress field, strain field and plastic failure zones in the surrounding rock mass of the underground cavities are summarized. The results show that the underground workshop building caverns are whole stable, but parts of them are unstable and the unstable parts are shallow. The results provide basic information and reference for the evaluation of underground cavities stability and project construction.

Yantan hydropower station lies in Hongshuihe in Yantan town, Dahua County, Guangxi. Four generating units of the first phase project of hydropower station had been built in 1995, the reservoir's normal water level is 223m, the maximum height of the concrete gravity dam is 110m, the powerhouse at the dam toe in right bank, and the installed capacity is 1210MW. The underground powerhouse of second phase extension project locates in the right mountain of the first phase powerhouse and dam project, including diversion tunnel, main powerhouse tunnel, main transformer cavern tunnel and tailrace tunnel etc., installed capacity is 2×300MW. The type of underground powerhouse is one unit with one tailrace tunnel in pressure, the maximum excavation width of over crane beam of main powerhouse is 30.8m and the length is 129m, the highest height difference of the powerhouse is 76.67m[1]. The water diversion and power generation system of extension project is placed in the mountain in the right bank, the thickness of overlying rocks is 75m~120m in the underground powerhouse area, and the surrounding rock is hard diabase. The diversion tunnel and underground powerhouse cavern group located in F48 fault footwall, the rock mass is relatively integrated and belongs to II class surrounding rock. The stress-deformation field of cavern surrounding rock will be changed by excavation of underground cavern group. On the basic of the excavated geological model, to simulate excavation of underground powerhouse cavern group in whole process by FLAC3D and analyze the change of stress field and deformation field. Many users at home and abroad have used the software[2~6], the results show that it has enough reliability and rationality. Particularly, its function is more powerful in deformation calculation and rock and soil mass stability analysis than finite element method.

The direction of valley is N160W. The altitude of low water level is 148m~150m, width of river level is 100m and water depth is 18m~20m. The lowest altitude of riverbed is 129m, both sides of riverbed are stone floodplains, the altitude floodplain face is 155m~168m. The two sides of riverbed is flood plain, flood plain altitude is 155m~168m. The first terrace over flood plain whose altitude is 185m ~200m. Landform of two banks is middle-low mountain whose altitude of crest is 500m, and its hillside gradient is 27°~36°.

ISRM-SINOROCK-2009-130

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

Industry:

- Energy > Power Industry > Utilities (0.69)
- Energy > Oil & Gas > Upstream (0.69)
- Energy > Renewable > Hydroelectric (0.55)

SPE Disciplines:

Technology:

- IT > Mathematics Of Computing (0.51)
- IT > AI > Representation & Reasoning (0.34)

The Punch-Through Shear with Confining Pressure (PTS/CP-) experiment has been proven to be a reliable testing method for the determination of Mode II fracture toughness. The Mode II fracture toughness, K

An alternative to the empirical continuum mechanics strength criteria are fracture mechanics based approaches. Linear fracture mechanics in general assumes preexisting discontinuities in a material that act as stress concentrators. The magnitude of the stress concentration governs the brittle fracture process. If pre-existing cracks or flaws are propagated by the stresses and coalesce to form larger discontinuities, the structures may loose integrity and fail. The mechanistic criteria try to mirror the physical origin of the processes and are therefore more exact.

Based on the principles of fracture mechanics, it is possible to not only asses the stability and safety of underground constructions, like caverns, tunnels or boreholes, but also to simulate – based on physical principles – the development of fractures in the vicinity of such openings. From the simulations the geometry of fracture patterns might be derived and used for different aspects, like fluid flow simulations. Some software packages are already available, e.g. Fracod2D, or under development.

Linear fracture mechanics provides the tools to estimate the stress and displacement fields around the tip of a discontinuity. Cracks or fractures are usually subdivided into three basic types, namely Mode I, Mode II and Mode III, based on the crack surface displacement (Lawn 1993; Fig. 1A). In Mode I, the tensile mode, the crack tip is subject to displacements perpendicular to the crack plane. In Mode II the crack faces move relatively to each other in the crack plane.

ISRM-SINOROCK-2009-141

ISRM International Symposium on Rock Mechanics - SINOROCK 2009

SPE Disciplines: