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Software Tutorials
Homogeneous Embankment Dam Analysis (Part 1 of 3)
This FLAC 8.1 tutorial demonstrates how to establish the stresses in the dry embankment prior to the formation of the upstream reservoir.
Plotting Borehole Core Data using Geometry and FISH
In this example, you will see how to create your own custom plot of drill core data containing location, orientation, depth, and geotechnical data (lithography. fracture count, rock strength, weathering, and RMR).
Loops, Splitting, and Operators
When constructing or running simulations, you may want to query or modify values associated with all, or some of, the objects in your model (such as zones, nodes, blocks, balls, contacts, rockbolts, etc.). This may be to measure results like stress or displacement, to assign a calculated extra variable for plotting or to adjust a property value. There are several ways to identify and navigate across all these objects using loops, splitting, and operators — with each one becoming easier and faster to execute. See how you can apply all of these approaches in a tutorial where a zone property is randomly assigned for strength variability throughout the model. You will also see how much easier and faster these approaches have become. Applying model property distributions via the PROPERTY command is also reviewed.
Technical Papers
Tunneldrivning i heterogena förhållanden
InledningProblem: Brist på erfarenhet av tunneldrivning i heterogena förhållanden med konventionell uttagsteknik (borrning och sprängning).
Mål: Fördjupa kunskapen och förståelse av brott och deformationsmönster vid dessa förhållanden.
Input to Orepass Design — A Numerical Modeling Study
Orepass design guidelines required for potentially continued mining at depth. Rock strength and stress state were validated through comparison with observed fallouts in orepasses and shafts and the optimal orientation and location of orepasses for future mining were determined.
Tunnelling and reinforcement in heterogeneous ground – A case study
Abstract
A case study of tunnelling in heterogeneous ground conditions has been analysed. The case involves a tunnel excavated in mixed-face conditions, where the main host material was rock, but for a distance of about 30 m, the tunnel had to be driven through a thick layer of soil, primarily moraine and sandy soil materials.During tunnel drifting, a "chimney" cave developed through the soil layer, resulting in a surface sinkhole.This case was analysed using a three-dimensional numerical model with the FLAC3D software code, in which the soil stratigraphy and tunnel advance were modelled in detail. Tunnel and soil reinforcement in the form of jet grouting of the soil, pipe umbrella arch system, bolting, and shotcreting, was explicitly simulated in the model. The studyaimed at comparing model results with observations and measurements of ground behaviour, and to replicate the major deformation pattern observed. The modelling work was based on a previous generic study in which various factors influencing tunnel and ground surface deformations were analysed for different cases of heterogeneous ground conditions.Model calibration was performed through adjusting the soil shear strength. The calibration provided a qualitatively good agreement with observed behaviour. Calculated deformations on the ground surface were in line with measured deformations, and the location of the tunnel collapse predicted by the model. The installed tunnel reinforcement proved to be critical to match with observed behaviour. Without installed pipe umbrella arch system, calculated deformations were overestimated, and exclusion of jet grouting caused collapse of the tunnel. These findings prove that, in particular, jet grouting of the soil layer was necessary for the successful tunnel advance through the soil layer.