Failure process analysis of a wedge-block failure in a drift at the Kiirunavaara mine
2011 (English)In: 45th U.S. Rock Mechanics / Geomechanics Symposium: American Rock Mechanics Association, Alexandria, Virginia: ARMA, American Rock Mechanics Association , 2011Conference paper (Refereed)
This paper presents a re-evaluation of a case study of an instrumented test drift in the Kiirunavaara mine. A 20 m long section of the test drift, located at the 514 m level in the Kiirunavaara mine, was instrumented in 1983, with the objective of studying the interaction of grouted rock bolts and hard rock masses subjected to changes in stresses induced by mining. During the test a large rock wedge was observed in the footwall side of the drift. Borehole extensometers, distometers, telescopic tube extensometers and rockbolts with strain gauges recorded the movement of the rock mass during the whole field measurement time. However, the actual failure process of the large wedge was not addressed in the original study. In this paper, this case was re-evaluated with the aim of increasing knowledge regarding of failure process of a large wedge in terms of deformation. A global-local numerical modeling approach was employed to reproduce the in situ conditions using the finite element program Phase2 and Universal Distinct Element Code (UDEC) software. The global approach was used to calculate the stresses induced during sublevel caving in the mine. The stresses from the global model were applied to the local model which simulated the test drift behavior, and in which geological structures were explicitly modeled. The deformation experienced by the rock mass due to the wedge in the drift was calculated in the local model and compared to the measured deformation in the field. The field measurement results showed that a small fallout occurred at the same location as the large wedge acted as initiator of the large wedge movement. The numerical modeling results showed that the large wedge did not fall out. The large wedge was characterized by shear displacements.
Place, publisher, year, edition, pages
Alexandria, Virginia: ARMA, American Rock Mechanics Association , 2011.
Civil engineering and architecture - Geoengineering and mining engineering
Samhällsbyggnadsteknik och arkitektur - Geoteknik och gruvteknik
Research subject Mining and Rock Engineering
IdentifiersURN: urn:nbn:se:ltu:diva-31072Local ID: 51fd3977-88d1-4ab5-a809-345027402821OAI: oai:DiVA.org:ltu-31072DiVA: diva2:1004301
U.S. Rock Mechanics / Geomechanics Symposium : 26/06/2011 - 29/06/2011
Godkänd; 2011; Bibliografisk uppgift: CD-ROM; 20111129 (kelper)2016-09-302016-09-30Bibliographically approved