自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
自然科学版 英文版
英文版编委
自然科学版 英文版
英文版首届青年编委

您目前所在的位置:首页 - 期刊简介 - 详细页面

中南大学学报(自然科学版)

Journal of Central South University

第48卷    第11期    总第279期    2017年11月

[PDF全文下载]    [Flash在线阅读]

    

文章编号:1672-7207(2017)11-3083-09
基于离散元分析盾构动态掘进引起的无黏性地层主应力特征
瞿同明1,王树英1, 2,傅金阳1,阳军生1

(1. 中南大学 土木工程学院,湖南 长沙,410075; 2. 重载铁路工程结构教育部重点实验室,湖南 长沙,410075)

摘 要: 为阐明土压平衡盾构掘进引起无黏性地层主应力响应特征,采用离散元方法建立土压平衡盾构动态掘进二维数值模型。在同一盾构掘进速率下,考虑不同土仓排土速率,分析盾构掘进引起的地表沉隆变化;取上、下2组极限排土工况,研究盾构掘进过程中排土速率引起的砂土地层主应力变化特征。研究结果表明:盾构掘进引起的地层主应力大小和方向的变化与土仓排土速率密切相关;在不排土工况下, 地层主应力的量值和偏转明显,掘进引起地层主应力响应的范围要比排土工况的大,且主应力比排土工况的更不容易达到稳定状态。在排土工况下,掌子面前方会形成明显的应力释放区;在同一排土速度下,掘进过程中地层大、小主应力随盾构掘进变化趋势相似,但变化的程度不同。

 

关键词: 土压平衡盾构;离散元;排土速度;主应力

Study on characteristics of principal stresses induced by dynamic EPB shield tunneling in non-cohesive stratum based on DEM
QU Tongming1, WANG Shuying1, 2, FU Jinyang1, YANG Junsheng1

1. School of Civil Engineering, Central South University, Changsha 410075, China; 2. Key Laboratory of Engineering Structure of Heavy Railway, Ministry of Education, Changsha 410075, China

Abstract:Two dimensional numerical simulations based on the discrete element method (DEM) were carried out to analyze the response characteristics of principal stress in non-cohesive stratum during the tunneling of the earth pressure balance (EPB) shield. Groups of shield tunneling cases with various soil-discharging speeds in the chamber and an identical advancing velocity were numerically conducted to investigate the changes of vertical displacement at ground surface. Two limit cases among those discharge speeds were determined to demonstrate the variations of principal stresses caused by tunneling. The results show that magnitudes and rotation angles of principal stress in stratum constantly vary and are closely related with soil-discharging speeds in chamber. In the case without discharging soil, magnitudes and directions of principal stress dramatically change and this affected area of stress is larger than that in the soil-discharging case, with a greater difficulty of keeping stress stable during tunneling. In the soil-discharging case, a remarkable stress release area forms in front of tunnel face. Furthermore, the variation tendencies of both major and minor principal stresses are similar in the case of identical discharge speeds, but the values of variation remain different from each other.

 

Key words: earth pressure balance shield; discrete element method; soil-discharging speed; principal stress

中南大学学报(自然科学版)
  ISSN 1672-7207
CN 43-1426/N
ZDXZAC
中南大学学报(英文版)
  ISSN 2095-2899
CN 43-1516/TB
JCSTFT
版权所有:《中南大学学报(自然科学版、英文版)》编辑部
地 址:湖南省长沙市中南大学 邮编: 410083
电 话: 0731-88879765(中) 88836963(英) 传真: 0731-88877727
电子邮箱:zngdxb@csu.edu.cn 湘ICP备09001153号