工程地质学报2017，Vol.25Issue(2)：308-316,9.DOI:10.13544/j.cnki.jeg.2017.02.006
高地应力条件下深埋洞室围岩损伤区孕育机制
EVOLUTION MECHANISM OF DAMAGE ZONE IN SURROUNDING ROCK MASS DURING EXCAVATION OF DEEP TUNNELS UNDER HIGH GEOSTRESS CONDITION
摘要
Abstract
As the development activities of human underground space goes to deep earth,the high geostress has become one of the typical geological characteristics of underground rock mass engineering and has an important effect on the safety and stability of surrounding rock mass.In this paper,the distribution regularities of geostress field in our country are firstly analyzed.And then,the damage of surrounding rock mass induced by quaSi-static unloading and transient unloading of geostress is studied by the methods of theoretical calculation and numerical simulation.At last,according to the testing results of damage in surrounding rock mass in Canada URL underground laboratory and diversion tunnels of Jinping Ⅱ hydropower station,the influence of unloading way of geostress on the damage formation of surrounding rock mass is analyzed.Results show that comparing with quasi-static unloading of geostress,transient unloading of geostress can produce an extra dynamic stress in surrounding rock mass and enlarge the unloading effect in radial and loading effect in tangent,which makes the surrounding rock mass easier to damage.In addition,the increase of lateral pressure coefficient can increase the damage range of surrounding rock mass induced by quasi-static unloading and transient unloading of geostress augments.In the direction of minimum principal stress,the main damage form of surrounding rock mass is shear failure.While in the direction of maximum principal stress,it shows as tension failure.关键词
高地应力/深埋洞室/准静态卸荷/瞬态卸荷/损伤Key words
High geostress/Deep tunnel/Quasi-static unloading/Transient unloading/Damage分类
建筑与水利引用本文复制引用
范勇,卢文波,周宜红,赵春菊,严鹏..高地应力条件下深埋洞室围岩损伤区孕育机制[J].工程地质学报,2017,25(2):308-316,9.基金项目
国家自然科学基金项目(51609127),湖北省自然科学基金项目(2016CFB238),国家重点基础发展计划(973)项目(2011CB076354)资助. （51609127）
