Technological innovations in construction of underground caverns in basaltic rocks at Baihetan Hydropower Station on Jinsha River

被引：0
|
作者：
Fan Q. [1 ]
Wang Z. [1 ]
He W. [1 ]
Lin P. [2 ]
Wang H. [1 ]
Xu J. [3 ]
Duan H. [1 ]
机构：
[1] China Three Gorges Corporation, Beijing
[2] Department of Hydraulic Engineering, Tsinghua University, Beijing
[3] PowerChina Huadong Engineering Corporation Limited, Hangzhou
来源：
Zhongguo Kexue Jishu Kexue/Scientia Sinica Technologica | 2021年 / 51卷 / 09期
关键词：
Baihetan Hydropower Station; Cavern group in basalt; Construction technologies; Spatio-temporal deformation control; Underground engineering;
D O I：
10.1360/SST-2021-0053
中图分类号：
学科分类号：
摘要：
The two underground powerhouses on the left and right banks of Baihetan Hydropower Station (BHT-HS) are symmetrically arranged inside basaltic rocks in the alpine gorge reach of the lower Jinsha River. Each of them is equipped with 8 sets of 1,000 MW hydraulic turbine generators, with the largest unit capacity, total installed capacity, span of main powerhouse (i.e. 34 m), diameter of dome-shaped tail-regulating chamber (max diameter of 48 m) and scale of underground caverns around the world. Due to complex layout, interaction between caverns and high hollowing rate, the construction process of the underground cavern group is faced many challenges. For example, the cavern excavation is located in the high ground stress area dominated by horizontal tectonic stress; the underlying basalt fractures are well developed, and the rock is hard and brittle, with low crack initiation strength; columnar jointed basalts develop locally; a number of large and weak gently-sloped shear zones develop diagonally cutting the main powerhouse. Following the construction ideology of "understanding, utilization, protection, monitoring, and feedback analysis on the surrounding rock masses during the construction period", and with the engineering construction procedure of "the excavation, analysis, prediction and inspection of each rock layer", this paper proposes a set of innovation construction technologies including "advanced pre-control, thin vertical layer, small planar partition, short excavation progress, fine blasting, strong and quick support, short interval monitoring, quick feedback, precise dynamic optimization" to control the internal cracking of the hard and brittle basaltic rocks, discontinuous deformation of staggered zones and spatio-temporal deformation of underground caverns in high geostress. It has promoted the safe and orderly construction of BHT-HS, the technical progress of the construction of hydropower station projects in China, and may also be applicable to the design and construction of similar projects worldwide. © 2021, Science Press. All right reserved.
引用
收藏
页码：1088 / 1106
页数：18
相关论文
共 32 条
  • [1] Fan Q X, Zhang C R, Chen W B, Et al., Key technologies of intelligent construction of Wudongde and Baihetan super high arch dams, J Hydroelectr Eng, 38, pp. 22-35, (2019)
  • [2] Fan Q, Zhou S, Yang N, Optimization design of foundation excavation for Xiluodu super-high arch dam in China, J Rock Mech Geotechnical Eng, 7, pp. 120-135, (2015)
  • [3] Fan Q X., Review of construction management and technical innovation of Xiangjiaba Hydropower Station, Yangtze River, 46, 2, pp. 1-4, (2015)
  • [4] Wang S L, Li C G, Shi G C, Et al., Analysis of underground powerhouses in Xiaowan Hydropower Station by elastic-brittle-plastic constitutive models, Chin J Rock Mech Eng, 24, pp. 4449-4454, (2005)
  • [5] Wu S, Shen M, Wang J, Jinping hydropower project: Main technical issues on engineering geology and rock mechanics, Bull Eng Geol Environ, 69, pp. 325-332, (2010)
  • [6] Fan Q, Zhu H, Chen X, Key issues in rock mechanics of the Three Gorges Project in China, J Rock Mech Geotechnical Eng, 3, pp. 329-342, (2011)
  • [7] Tang J F, Xu G Y, Tang X M, Et al., Surrounding rock mass stability analysis by using 3DEC and informational construction of Xiangjiaba underground cavern group, J Hunan Univ Sci Technol (Nat Sci Edit), 24, pp. 67-72, (2009)
  • [8] Liu G F, Feng X T, Jiang Q, Et al., Failure characteristics, laws and mechanisms of rock spalling in excavation of large-scale underground powerhouse caverns in Baihetan, Chin J Rock Mech Eng, 35, pp. 865-878, (2016)
  • [9] Xiao Y H, Huang X Q, Liu C P, Et al., Study on engineering geological problems of underground powerhouses of Wudongde Hydropower Station, Yangtze River, 46, 14, pp. 1-3, (2015)
  • [10] Lu B, Wang J M, Ding X L, Et al., Study of deformation and cracking mechanism of surrounding rock of Jinping I underground powerhouse, Chin J Rock Mech Eng, 29, pp. 2429-2411, (2010)
1234