TY - JOUR
T1 - Numerical analysis of collapse in a deep excavation supported by ground anchors
AU - Baziar, Mohammad Hassan
AU - Ghadamgahi, Alireza
AU - Brennan, Andrew John
N1 - Publisher Copyright:
© 2020 ICE Publishing: All rights reserved.
PY - 2021/6
Y1 - 2021/6
N2 - On 3 October 2013, a global failure occurred in one of the stabilised sections of a deep excavation in Shahrak-e gharb in Tehran. The excavation was supported by ground anchors with enlarged reinforced concrete thrust blocks and sprayed concrete facing. The failure occurred despite the system passing conventional limit equilibrium design and satisfying requirements in terms of allowable displacements. The case of Shahrak-e gharb was modelled using Abaqus in order to understand the soil deformation leading to the failure condition. It was found that a near-surface zone of weaker fill material was responsible for the failure. As the displacements during construction and the soil failure mechanisms were well matched by the numerical model, the case study was considered to be a validation case for the numerical model and a parametric study on the extent to which anchoring bypassed the weaker surface soil was performed. This study showed that proper embedment into competent soils is important as excessive strains can still develop if the anchor bond zone is insufficiently confined, potentially leading to progressive collapse.
AB - On 3 October 2013, a global failure occurred in one of the stabilised sections of a deep excavation in Shahrak-e gharb in Tehran. The excavation was supported by ground anchors with enlarged reinforced concrete thrust blocks and sprayed concrete facing. The failure occurred despite the system passing conventional limit equilibrium design and satisfying requirements in terms of allowable displacements. The case of Shahrak-e gharb was modelled using Abaqus in order to understand the soil deformation leading to the failure condition. It was found that a near-surface zone of weaker fill material was responsible for the failure. As the displacements during construction and the soil failure mechanisms were well matched by the numerical model, the case study was considered to be a validation case for the numerical model and a parametric study on the extent to which anchoring bypassed the weaker surface soil was performed. This study showed that proper embedment into competent soils is important as excessive strains can still develop if the anchor bond zone is insufficiently confined, potentially leading to progressive collapse.
KW - Anchors & anchorages
KW - Excavation
KW - Failure
UR - http://www.scopus.com/inward/record.url?scp=85108112721&partnerID=8YFLogxK
U2 - 10.1680/jgeen.19.00122
DO - 10.1680/jgeen.19.00122
M3 - Article
VL - 174
SP - 263
EP - 278
JO - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering
JF - Proceedings of the Institution of Civil Engineers: Geotechnical Engineering
SN - 1353-2618
IS - 3
ER -