Study on Excavation of Particular Part of Underground Cavern for Hydropower Station

2017 3rd International Conference on Environmental Science and Material Application

生态环境科学;材料科学

Yang, Yang^1 ; Zhang, Feng^1 ; Shang, Qin^1 ; Zheng, Huakang^1

Changjiang Institute of Survey, Planning, Design and Research, Wuhan

430010, China^1

关键词: Finite element numerical simulation;    Hydropower stations;    Local and global stabilities;    Surrounding rock;    Tailrace tunnel;    Thin layers;    Underground cavern;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/108/3/032072/pdf
DOI  :  10.1088/1755-1315/108/3/032072

来源: IOP

【 摘 要 】

In the present study, regarding four particular parts of underground cavern for hydropower station, i.e., crown, high sidewall, the intersection between high sidewall and tunnel and tailrace tunnel, by summarizing the previous construction experience, we have proposed the excavation approach based on "middle first and edge later, soft first and hard later", "layered construction by excavating the thin layer first and supporting as the layer advances", "tunnel first and wall later, small tunnels into large ones" and "excavating tunnels supported by separation piers". In addition, the proposed excavation approach has been analyzed and verified with finite element numerical simulation. The result has indicated that the proposed special approach is reasonable and effective to reduce the turbulence on surrounding rocks, lower the influence of unloading during excavating and enhance the local and global stability of caverns and surrounding rocks.