RESEARCH ARTICLE
The Collapse Mechanism and Anchored Effect of Bolt-supported Tunnel in Soft Ground
Linjie Chen, Feng Huang*
Article Information
Identifiers and Pagination:
Year: 2016Volume: 10
First Page: 759
Last Page: 767
Publisher ID: TOCIEJ-10-759
DOI: 10.2174/1874149501610010759
Article History:
Received Date: 14/03/2016Revision Received Date: 31/07/2016
Acceptance Date: 25/08/2016
Electronic publication date: 30/11/2016
Collection year: 2016
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution-Non-Commercial 4.0 International Public License (CC BY-NC 4.0) (https://creativecommons.org/licenses/by-nc/4.0/legalcode), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Abstract
The instability even collapse of tunnel would occur during the construction in soft ground. A collapse of expressway tunnel which suddenly encountered soft ground took place just after completing the anchor bolts was investigated as the study background. Based on the plastic and damage constitutive laws, the numerical method of finite element was funded for analyzing the failure mechanism of anchored rock mass and support effects of bolts. Some results were concluded as following by comparing the numerical calculations and field investigations, which would be adopted in further similar engineering. The tunnel collapse is a progressive process with the damage evolution and stress redistributions. The failure zone concentrated near the tunnel crown which can be considered to be the main load on the tunnel structure. According to the length of bolts increases or the spacing distance of bolts decreases, the loosening zones, damage zones, and failure zones will simultaneously become less and less. Nevertheless, those effects become less obvious when the length increases more than 5m or the spacing decreases less than 1m in practice.
