Search for dissertations about: "dfn"

Showing result 1 - 5 of 8 swedish dissertations containing the word dfn.

2. 1. Fractured Rock Masses as Equivalent Continua - A Numerical Study

   Author : Ki-Bok Min; KTH; []
   Keywords : fractured rock masses; equivalent continuum; discrete fracture Network DFN ; Distinct Element Method DEM ; Finite Element Method FEM ; Nuclear Waste Disposal; Coupled Thermo-Hydro-Mechanical Processes;

   Abstract : In this thesis, fractured rock masses are treated asequivalent continua for large-scale analyses of rockengineering projects. Systematic developments are made for thedetermination of equivalent mechanical and hydraulic propertiesof fractured rock masses using a hybrid discrete fracturenetwork - distinct element method (DFN-DEM) approach. READ MORE

4. 2. Strength and deformability of fractured rocks

   Author : Majid Noorian-Bidgoli; Lanru Jing; John A. Hudson; KTH; []
   Keywords : Fractured crystalline rocks; Numerical experiments; Discrete element methods DEM ; Discrete fracture network DFN ; Representative elementary volume REV ; Coupled hydro-mechanical processes; Anisotropy; Effective stress; Failure criteria; Stochastic realizations; Land and Water Resources Engineering; Mark- och vattenteknik;

   Abstract : This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. READ MORE

5. 3. Scale and Stress Effects on Hydro-Mechanical Properties of Fractured Rock Masses

   Author : Alireza Baghbanan; Lanru Jing; Jian Zhao; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Aperture-trace length correlation; Discrete Fracture Network DFN ; Representative Elementary Volume REV ; Strength; Stress-Strain curve; Discrete Element Method DEM ; Stress effect; Deformability of fractures; Earth sciences; Geovetenskap;

   Abstract : In this thesis, the effects of size and stress on permeability, deformability and strength of fractured rock masses are investigated. A comparison study was carried out to examine the effects of considering, or not considering, the correlation between distributions of fracture apertures and fracture trace lengths on the hydro-mechanical behavior of fractured rocks. READ MORE

6. 4. Model uncertainty of design tools to analyze block stability

   Author : Mehdi Bagheri; Håkan Stille; Mats Holmberg; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Block failure is one of the most common failure modes in tunnels. Design tools have some simplifications and, therefore, they also have some model uncertainties. The purpose of this licentiate thesis is to assess the model uncertainty for different design tools in order to estimate block stability. READ MORE

7. 5. Upscaling of Flow, Transport, and Stress-effects in Fractured Rock

   Author : Johan Öhman; Auli Niemi; Ove Stephansson; Robert W Zimmerman; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hydrology; Upscaling; fractured media; flow; solute transport; thermo-hydro-mechanical processes; hybrid approach; continuum approximation; discrete fracture network; stochastic continuum; Hydrologi; Hydrology; Hydrologi;

   Abstract : One of many applications of geohydraulic modelling is assessing the suitability of a site to host a nuclear waste repository. This modelling task is complicated by scale-dependent heterogeneity and coupled thermo-hydro-mechanical (THM) processes. READ MORE