[最新文献]耦合的网格/离散单元法模拟岩石粘结块体 [11/14/2020]

1 论文

Hybrid lattice/discrete element method for bonded block modeling of rocks 耦合的网格/离散单元法模拟岩石粘结块体

Abstract: The Hybrid Lattice/Discrete Element Method is proposed for Bonded Block Modeling of rocks. The method is a combination of the Rigid Body Spring Network Lattice Model with the Discrete Element Method. The main advantages of the new method are: (i) it operates based on either a homogeneous or heterogeneous material assumption, with heterogeneity being represented by means of the Weibull probability distribution applied to elasticity and strength parameters; and (ii) it provides for a direct material calibration scheme for rock models based on both assumptions, which does not require trial-and-error iterations. Thirteen rock types, including igneous, metamorphic, and sedimentary ones were simulated in the two-dimensional version of the method considering both assumptions, and their numerical macroscale properties were compared to the laboratory ones. Results show that while deformability and peak strength properties were accurately represented by the homogeneous models, linear elastic-brittle behavior manifested. On the other hand, the heterogeneous models presented non-linear stress–strain behavior and provided reasonable matches for the following laboratory properties: Young modulus, Poisson’s ratio, crack initiation stress, crack damage stress, unconfined compression strength, and direct tensile strength.

Keywords: Hybrid LDEM DEM RBSN lattice model Calibration Bonded block model Heterogeneity

摘要：针对岩石粘结块体模拟，提出了耦合的网格/离散单元法。该方法是刚体弹簧网格模型与离散单元法的结合。新方法的主要优点是。(一)它的操作基于均质或非均质材料假设，非均质性通过应用于弹性和强度参数的Weibull概率分布来表示；(二)它为基于两种假设的岩石模型提供了直接的材料校准方案，不需要试错迭代。考虑到这两种假设，在该方法的二维版本中模拟了13种岩石类型，包括火成岩、变质岩和沉积岩，并将其数值宏观特性与实验室特性进行了对比。结果表明，当变形特性和峰值强度特性被均质模型准确地表示出来后，线性弹性脆性行为表现出来。另一方面，非均质模型呈现出非线性应力-应变行为，并为下面实验室性质提供了合理的匹配,包括杨氏模量、泊松比、裂纹起始应力、裂纹破坏应力、单轴抗压强度和直接抗拉强度。

2 相关文献

Note: '相关文献' 是按照Google的排序算法产生出来的.

[1] A hybrid discrete bubble-lattice Boltzmann–discrete element model for gas-charged sediments

[2] Overview of the numerical methods for the modelling of rock mechanics problems 

[3] Advances in Discrete Element Method Applied to Soil, Rock and Concrete Mechanics

[4] Applications of Finite/Discrete Element Modeling to Rock Engineering Problems

[5] Advances in the Development of the Discrete Element Method for Excavation Processes

[6] An overview on advances in computational fracture mechanics of rock

Lattice Element Method and its application to Multiphysics

[7] Modelling blast induced damage from a fully coupled explosive charge

[8] Modeling acoustic emissions in heterogeneous rocks during tensile fracture with the Discrete Element Method

[9] The use of discrete fracture networks for modelling coupled geomechanical and hydrological behaviour of fractured rocks

3 网格-弹簧法

网格-弹簧法LS(lattice-spring-based method) 由Cundall and Damjanac (2009)提出，并在Itasca内部开发(目前还没有商业发布)了一个相应的软件称之为Slope Model, 用来分析脆性断裂的岩体边坡稳定性。之后主要由加拿大的一些大学包括UBC, University of Alberta, SFU，Laurentian University的岩石力学研究人员以及Itasca公司自身继续扩展了这项研究。

LS的核心算法是PFC，它将PFC模型中的颗粒用节点代替，用弹簧表示键与键之间的接触，完整的岩石断裂用弹簧的断裂来表示。通过创建一个合成岩体模型SRM, 允许节理滑动和张开以及完整岩石的断裂。这种分析方法从用户指定的DFN得出的节理形状，然后对节理网络内的非稳态流体流动和压力进行模拟，地下水可以在节理和岩石中流动，当新的裂缝形成时，流动网络也会自动扩展。

4 参考文献

[1] Cundall, P. A. and Damjanac, B. 2009. A comprehensive 3D model for rock slopes based on micromechanics. Proceedings of the Slope Stability 2009 Conference, Santiago, Chile, 10pp.

[2]Havaej, M., Stead, D., Eberhardt, E. and Fisher, B. 2014a. Characterization of bi-planar and ploughing failure mechanisms in footwall slopes using numerical modelling. Eng. Geol., 178:109–20.

[3] Havaej, M., Stead, D., Mayer, J. and Wolter, A. 2014b. Modelling the relation between failure kinematics and slope damage in high rock slopes using a lattice scheme approach, Proc. ARMA 2014, Minneapolis, Paper #14-7374, 8pp.

[4] Havaej, M., A. Wolter and D. Stead. (2015) “The possible role of brittle rock fracture in the 1963 Vajont Slide, Italy,” Int. J. of Rock Mechanics & Mining Sciences, 78, pp. 319-330.

[5] Havaej, M. and D. Stead. (2016) “Investigating the Role of Kinematics and Damage in the Failure of Rock Slopes,” Computers and Geotechnics, 78, pp. 181-193.

[6] Tuckey, Z., D. Stead, M. Havaej, F. Gao, and M. Sturzenegger. (2012) “Towards an Integrated Field Mapping-Numerical Modelling Approach for Characterising Discontinuity Persistence and Intact Rock Bridges in Large Open Pits,” in GeoManitoba, Building on the Past (Proceedings, 65th Canadian Geotechnical Conference, Winnipeg, September 30-October 3, 2012), Paper 182. Toronto: Canadian Geotechnical Society.

[7] Tuckey, Z. (2012) An Integrated Field Mapping-Numerical Modelling Approach to Characterising Discontinuity Persistence and Intact Rock Bridges in Large Open Pit Slopes. MS Thesis, Simon Fraser University.

[8] Becerra, J.V. (2014) Groundwater Characterization and Modelling in Natural and Open Pit Rock Slopes. MS Thesis, Simon Fraser University.

[9] Bastola, S. and M. Cai (2020). "Investigation of mechanical properties of jointed granite under compression using lattice-spring-based synthetic rock mass modeling approach." International Journal of Rock Mechanics and Mining Sciences 126.

[10] Bastola, S. and M. Cai (2019). "Investigation of mechanical properties and crack propagation in pre-cracked marbles using lattice-spring-based synthetic rock mass (LS-SRM) modeling approach." Computers and Geotechnics 110: 28-43.

[11] Vivas Becerra, J., Hunt, C., Stead, D., Allen, D. and Elmo, D. 2015. Characterising groundwater in rock slopes using a combined remote sensing-numerical modelling approach. Proceedings of the International Congress of Rock Mechanics, ISRM, Montreal, Canada, Paper No. 670.

离散断裂网络(DFN)[P4]: 创建一个合成岩体SRM

网格-弹簧(Lattice-Spring-Based)方法

一个阶段性的小结: 离散断裂网络DFN

离散断裂网络(DFN)[P3]: fracture contact-model

离散断裂网络 (DFN) [P2]: fracture generate