摘要
自然界中的岩体在长期的地质构造运动作用下,内部往往发育不同尺度的节理,而巷道围岩的稳定性与节理的发育密切相关。为研究节理对巷道围岩开挖卸荷变形的影响,采用课题组的开挖卸荷模型试验系统,对不同节理尺寸水泥砂浆围岩试件开展了系列试验。研究结果表明:(1)巷道围岩开挖卸荷变形主要发生在卸荷阶段,维持阶段变形继续存在,但节理对其卸荷变形无明显影响。此阶段,卸荷变形程度显著降低并逐渐趋于稳定,其应变增量大约为100με;(2)与无节理试件相比,含节理试件S-1和S-2的应变平均降低幅度超过70%,远高于S-3,即节理尺寸越大,卸荷变形程度越大,卸荷作用越明显;(3)试件在不同方向的应变差异较大,切向应变均大于径向应变,含节理试件尤为突出。
The rock mass in nature often develops joints of different scales under the action of long-term geological tectonic movement,and the stability of surrounding rock of roadways has a great relationship with the development of joints.For the sake of studying the effects of joints on the excavation unloading deformation of surrounding rock of roadways,a series of tests are carried out on the cement mortar surrounding rock specimens with different joint sizes through the excavation unloading model test system developed by the authors.The results show that:(1)The unloading deformations of surrounding rock mainly occur at the unloading stage,and the deformations continue to exist at the maintenance stage,but the joints have no obvious influences on the unloading deformations.At this stage,the unloading deformation degree decreases significantly and gradually becomes stable,with the strain increment of about 100με.(2)Compared with the specimens without joints,the average strain reduction of S-1 and S-2 specimens with joints is more than 70%,which is much higher than S-3.That is,the larger the joint size,the greater the degree of unloading deformations,and the more obvious the unloading effects.(3)The specimens have great differences in strain in different directions,and the tangential strain is greater than the radial strain,especially for the specimens with joints.
作者
侯公羽
邵耀华
刘春雷
王一哲
陈钦煌
胡志宇
赵庆儒
HOU Gongyu;SHAO Yaohua;LIU Chunlei;WANG Yizhe;CHEN Qinhuang;HU Zhiyu;ZHAO Qingru(School of Mechanics and Civil Engineering,China University of Mining and Technology,Beijing 100083,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2024年第3期616-623,共8页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金委员会与2020年度高速铁路基础研究联合基金资助重点项目(U2034205)。
关键词
小型模型试验
节理
开挖卸荷
围岩变形
small-scale model test
joint
excavation unloading
surrounding rock deformation
