Software Tutorials
Working with Email in Itasca Software
Learn how you can use commands and functions to send email messages and attachments via Itasca software. Use this capability to inform you when a model has finished running, a result is available (even attach a plot), or the model run is interrupted.
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.
FLAC3D 7.0 Geometry Mesh Tutorial
This tutorial demonstrates how to generate a 3D volume mesh from surface geometry imported from DXF or STL files. Both hexahedral-dominant and tetrahedral meshes can be generated automatically using the "zone generate from-geometry ..." command in FLAC3D 7. The results of various keywords are shown.
Technical Papers
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.
On the Density Variability of Poissonian Discrete Fracture Networks, with application to power-law fracture size distributions
This paper presents analytical solutions to estimate at any scale the fracture density variability associated to stochastic Discrete Fracture Networks. These analytical solutions are based upon the assumption that each fracture in the network is an independent event. Analytical solutions are developed for any kind of fracture density indicators.
A Strategic Rock Mechanics Study for The Kevitsa Open Pit Mine
The Boliden Kevitsa open pit mine is revising its strategic plan with a new pit optimization project undertaken to investigate an increase in production.