Software Tutorials
Plotting 3D Isosurfaces
This tutorial demonstrates how you can add isosurfaces to your 3D Itasca model plots.
Homogeneous Embankment Dam Analysis (Part 2 of 3)
This FLAC 8.1 tutorial demonstrates how to conduct a steady-state seepage analysis to calculate the pore water pressures in the embankment due to the reservoir.
MINEDW Tutorial (Part 3: Boundary Conditions)
In this tutorial we will take a look at the different boundary conditions available to the user, and we will go over some examples of different scenarios in which they would be used.
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.
The nexus between groundwater modeling, pit lake chemogenesis and ecological risk from arsenic in the Getchell Main Pit, Nevada, U.S.A.
The proliferation of mine pits that intersect the groundwater table has engendered interest in environmental consequences of the lakes that form after cessation of dewatering.
Depressurising an Underground Ore Body at the McArthur River Mine in Northern Saskatchewan, Canada
Pre-mining depressurising of a deep ore body at the McArthur River mine in northern Saskatchewan was considered to decrease the risk associated with mining near 5 MPa water pressure and increasing the amount of ore that can be extracted.