Optimal Support Design for Galleries Located in Poor Quality Rock Mass and Under the Influence of Mining Works

In this work, the support of two general galleries located in poor quality rock mass and subjected to the influence of high thickness coal layer exploitations is designed and optimized. The process is carried out in four phases: A first preliminary support is defined employing different geomechanica...

Full description

Saved in:
Bibliographic Details
Published in:Archives of mining sciences = Archiwum górnictwa 2020-01, Vol.65 (4), p.851
Main Authors: Vázquez-Silva, Daniel, Prendes-Gero, Maria-Belen, Álvarez-Fernández, Martina-Inmaculada, González-Nicieza, Celestino, Laín-Huerta, Carlos, López-Gayarre, Fernando
Format: Article
Language:English
Subjects:
Arches
Bolts
Coal
Design
Exploitation
Failure analysis
Galleries
Geomechanics
Instrumentation
Mines
Mining
New Austrian Tunnelling Method
Placement
Rock masses
Rocks
Sprayed concrete
Steel structures
Sublevel caving
Thickness
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In this work, the support of two general galleries located in poor quality rock mass and subjected to the influence of high thickness coal layer exploitations is designed and optimized. The process is carried out in four phases: A first preliminary support is defined employing different geomechanical classifications and applying the New Austrian Tunnelling Method (NATM) using bolts and shotcrete. An instrumentation campaign is carried out with the goal of analysing the behaviour of the support. The study noticed the failure of the support due to the time of placement of the different elements. A back-analysis using the Flac and Phases software has allowed the evaluation of the properties of the rock mass and the support, the study of the influence of the time of placement on the component elements (bolts and shotcrete), and the redefinition of that support. Subsequently, a new support is designed and optimized through numerical modeling after the start of mining without experience in these sizes of sublevel caving that caused the failure of the previously designed support. The new support is formed by yieldable steel arches that are more suitable to withstand the stresses generated by nearby mining work.
ISSN:0860-7001
1689-0469
DOI:10.24425/ams.2020.135181