Interaction between shotcrete and rock : experimental and numerical study
At LKAB’s underground mines in Malmberget and Kiruna in northern Sweden shotcrete and rock bolts are the main rock support elements. A safe working environment for the miners and high accessibility to the mine are important issues. To address these issues and to improve the use of the support, LKAB...
Main Author: | |
---|---|
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
Luleå
2005
|
Subjects: | |
Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18759 |
id |
ftluleatu:oai:DiVA.org:ltu-18759 |
---|---|
record_format |
openpolar |
spelling |
ftluleatu:oai:DiVA.org:ltu-18759 2023-05-15T17:04:22+02:00 Interaction between shotcrete and rock : experimental and numerical study Malmgren, Lars 2005 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18759 eng eng Luleå Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, 1402-1544 2005:48 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18759 Local a2d4e790-515a-11db-9592-000ea68e967b info:eu-repo/semantics/openAccess Other Civil Engineering Annan samhällsbyggnadsteknik Doctoral thesis, comprehensive summary info:eu-repo/semantics/doctoralThesis text 2005 ftluleatu 2022-10-25T20:51:00Z At LKAB’s underground mines in Malmberget and Kiruna in northern Sweden shotcrete and rock bolts are the main rock support elements. A safe working environment for the miners and high accessibility to the mine are important issues. To address these issues and to improve the use of the support, LKAB initiated a doctoral thesis study on the interaction between its rock support system and the rock. The objectives of this thesis were: to identify important parameters involved in the interaction between shotcrete and rock and if necessary investigate important quantities of these parameters, to improve the understanding of the interaction of shotcrete and rock. To achieve the first objective a number of laboratory and field tests were carried out. The second objective was achived by numerical analyses. The main conclusions are: The analyses showed that the rock strength and the unevenness of the surface had a large impact on the number of failures at the interface and in the lining. Furthermore, the behaviour of the lining was sensitive to small amplitudes of the surface roughness. A high bond strength was favourable according to the analyses. The results from the field tests showed the importance of the bond at the interface. If bond failure occurs the ability to distribute and control the crack width ceases. Failure mapping in the mine showed that that a thin shotcrete layer (<20 mm) did not perform well. It is therefore, important that the designed thickness is achieved when shotcreting. The extent of the excavated damage zone had a minor effect on the behaviour of the shotcrete lining if the surface was uneven. For an even surface, the influence of the extent of the EDZ on shotcrete was obvious but not serious. The rock support is generally designed for static loading conditions. In many cases, however, the openings are also subjected to dynamic loads. By field tests, vibration measurements and analyses the influence from blasting induced stress waves on the performance of shotcrete was investigated. The main ... Doctoral or Postdoctoral Thesis Kiruna Malmberget Northern Sweden Luleå University of Technology Publications (DiVA) Kiruna |
institution |
Open Polar |
collection |
Luleå University of Technology Publications (DiVA) |
op_collection_id |
ftluleatu |
language |
English |
topic |
Other Civil Engineering Annan samhällsbyggnadsteknik |
spellingShingle |
Other Civil Engineering Annan samhällsbyggnadsteknik Malmgren, Lars Interaction between shotcrete and rock : experimental and numerical study |
topic_facet |
Other Civil Engineering Annan samhällsbyggnadsteknik |
description |
At LKAB’s underground mines in Malmberget and Kiruna in northern Sweden shotcrete and rock bolts are the main rock support elements. A safe working environment for the miners and high accessibility to the mine are important issues. To address these issues and to improve the use of the support, LKAB initiated a doctoral thesis study on the interaction between its rock support system and the rock. The objectives of this thesis were: to identify important parameters involved in the interaction between shotcrete and rock and if necessary investigate important quantities of these parameters, to improve the understanding of the interaction of shotcrete and rock. To achieve the first objective a number of laboratory and field tests were carried out. The second objective was achived by numerical analyses. The main conclusions are: The analyses showed that the rock strength and the unevenness of the surface had a large impact on the number of failures at the interface and in the lining. Furthermore, the behaviour of the lining was sensitive to small amplitudes of the surface roughness. A high bond strength was favourable according to the analyses. The results from the field tests showed the importance of the bond at the interface. If bond failure occurs the ability to distribute and control the crack width ceases. Failure mapping in the mine showed that that a thin shotcrete layer (<20 mm) did not perform well. It is therefore, important that the designed thickness is achieved when shotcreting. The extent of the excavated damage zone had a minor effect on the behaviour of the shotcrete lining if the surface was uneven. For an even surface, the influence of the extent of the EDZ on shotcrete was obvious but not serious. The rock support is generally designed for static loading conditions. In many cases, however, the openings are also subjected to dynamic loads. By field tests, vibration measurements and analyses the influence from blasting induced stress waves on the performance of shotcrete was investigated. The main ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Malmgren, Lars |
author_facet |
Malmgren, Lars |
author_sort |
Malmgren, Lars |
title |
Interaction between shotcrete and rock : experimental and numerical study |
title_short |
Interaction between shotcrete and rock : experimental and numerical study |
title_full |
Interaction between shotcrete and rock : experimental and numerical study |
title_fullStr |
Interaction between shotcrete and rock : experimental and numerical study |
title_full_unstemmed |
Interaction between shotcrete and rock : experimental and numerical study |
title_sort |
interaction between shotcrete and rock : experimental and numerical study |
publisher |
Luleå |
publishDate |
2005 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18759 |
geographic |
Kiruna |
geographic_facet |
Kiruna |
genre |
Kiruna Malmberget Northern Sweden |
genre_facet |
Kiruna Malmberget Northern Sweden |
op_relation |
Doctoral thesis / Luleå University of Technology 1 jan 1997 → …, 1402-1544 2005:48 http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18759 Local a2d4e790-515a-11db-9592-000ea68e967b |
op_rights |
info:eu-repo/semantics/openAccess |
_version_ |
1766058440785920000 |