1. Geotechnical and Structural Engineering Research Center, Shandong University, Jinan 250061, China;
2. School of Qilu Transportation, Shandong University, Jinan 250002, China
Abstract： The synergistic action of surrounding rock and support is the core issue in the support design of underground engineering, which is closely related to the success or failure of underground engineering construction. In order to reveal the synergistic mechanism of rock and support in deep tunnels, the true 3D geo-mechanical model test for the synergistic action of lining and rock mass under complex geological conditions was conducted for the Xianglushan tunnel in the Central Yunnan Water Diversion Project, so that the whole process of tunnel excavation and support is truly reproduced. The model test results indicate that：(1) The stress release processes of surrounding rock around the tunnel are different for different geological conditions. The stress release rate of surrounding rock in hard rock is slow at first and then tends to be quicker, but in soft rock, it is quick at first and then tends to be slower; (2) the distribution patterns of the contact pressure between the lining and the surrounding rock are different for different geological conditions. For hard rock, the maximum contact pressure is located at the spandrel, but in soft rock the maximum contact pressure is located at the vault; (3) During the process of tunnel construction, the synergistic action of lining-rock includes two types of stress release mechanisms, three construction stages and four load bearing states; (4) For different geological conditions, the load bearing ratio of the surrounding rock and lining is different after the construction of tunnel lining. For hard rock, the surrounding rock may bear about 85% of the total excavation load, and the lining may take about 15% of the total excavation load; for soft rock, the surrounding rock may bear about 25% of the total excavation load, and the lining may take about 75% of the total excavation load. The model test results can provide important test references for the development of the construction scheme and the optimization of support design in deep tunnel under complicated geological conditions.
任明洋 张强勇 陈尚远 尹相杰 李 帆 向 文 余光远. 复杂地质条件下大埋深隧洞衬砌与围岩协同作用#br#
物理模型试验研究[J]. 土木工程学报, 2019, 52(8): 98-109.
Ren Mingyang Zhang Qiangyong Chen Shangyuan Yin Xiangjie Li Fan Xiang Wen Yu Guangyuan. Physical model test study on synergistic action of lining-rock for deep tunnel under complex geological conditions. 土木工程学报, 2019, 52(8): 98-109.
