Temperature Field Development Characteristics of Frozen Method Construction for Metro Link Passages in Shanghai Soft Soil Stratum
Journal Title: Urban Mass Transit - Year 2024, Vol 27, Issue 1
Abstract
[Objective] In order to predict the development of the frozen wall before the frozen method construction and validate the rationality of the design, providing a scientific guidance for engineering construction, it is necessary to study the temperature field development law of frozen method construction for Shanghai Metro link passages in soft soil stratum, and propose evaluation and economic indicators. [Method] Taking an interval of Shanghai Rail Transit Line 15 as engineering background, the frozen wall thickness, soil temperature, brine temperature, and freezing process are analyzed. A three-dimensional numerical model of the entire stratum is established using ABAQUS finite element software to predict the development characteristics of the frozen temperature field and verify it with field-measured temperature data. [Result & Conclusion] The average development speed of the clay layer frozen curtain is 54.535 mm/day, while the average development speed of the silty clay layer frozen curtain is 52.450 mm/day, indicating a better freezing effect of the former. Considering the relatively weak freezing effect at the end profile of the freezing pipe, the thickness of the weak-side frozen wall and the average temperature at that profile are adopted as the freezing effect evaluation indicators, thereby reducing the possibility of structural damage. The influence of brine temperature on the development of frozen wall thickness weakens with decreasing temperature, with the highest economic benefit observed between -30 ℃ and -35 ℃. The simulation results are consistent with the overall cooling trend of the field-measured data, providing a relatively realistic reflection of the actual construction process.
Authors and Affiliations
Haonan ZHAO, Caichu XIA, Xingkai WANG
Keywords
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- EP ID EP727698
- DOI 10.16037/j.1007-869x.2024.01.015
- Views 44
- Downloads 0
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