Technical gazette, Vol. 28 No. 3, 2021.
Original scientific paper
https://doi.org/10.17559/TV-20200719051620
Analysis on the Appropriate Buried Depth of the Cold-proof Drainage Hole of the Tunnel in the Cold Region
Maolong Zhao*
; Shaanxi Highway Group Co. LTD, Xi'an 710075, China
Wei Zhu
; Shaanxi Hengtai Highway Technology Co. LTD, Xi'an 710075, China
Abstract
A cold-proof drainage hole is an effective measure to prevent freezing injury of a tunnel in a cold region. However, the construction technology and insulation effect of the cold-proof drainage hole only focused on existing research. This study used MIDAS/GTS for modelling based on a tunnel in cold region of Qinghai Province, China to determine the suitable buried depth of a cold-proof drainage tunnel from the mechanical properties and variation of deformation of tunnel in cold region. The working conditions of first excavating the main tunnel and then the cold-proof drainage hole were set. The variation rules of displacement, stress, and plastic zone of the main tunnel and the cold-proof drainage hole under different buried depths were analyzed. The interaction mechanism between the main tunnel and the cold-proof drainage tunnel under different buried depths was revealed. Results show that: the structure of main tunnel hole is interplayed with that of cold-proof drainage hole; from the point of displacement change rule, the optimal effective buried depth for cold-proof drainage hole of a tunnel in China's Qinghai Province is from 5 m to 6 m; from the point of stress change rule, the optimal effective buried depth for the cold-proof drainage hole is also from 5 m to 6 m; from the point of plastic zone change rule, the optimal effective buried depth for the cold-proof drainage hole is from 4 m to 6 m considering the stress uniformity of support and material for cold-proof drainage hole. The effective buried depth of the cold-proof drainage hole is confirmed to be 5 m. The results of finite element analysis are consistent with the field monitoring results, thereby verifying the reliability of the analytical results in this study. This study has guiding significance for the construction of the cold-proof drainage tunnel in the cold region.
Keywords
buried depth; China's Qinghai province; cold-proof drainage hole; MIDAS/GTS; tunnelling engineering
Hrčak ID:
258224
URI
Publication date:
6.6.2021.
Visits: 1.343 *