Study on the Reasons and Countermeasure of Ground Subsidence Caused by Slurry Shield Construction Covered by a Giant Thick Rock Formation
(1. Engineering Case Committee of Chinese Society for Rock Mechanics & Engineering, Guangzhou 510000; 2. Guangzhou Mass Transit Engineering Consultant Co., Ltd., Guangzhou 510000)
Abstract：
It is generally recognized in the industry that slurry shield construction is superior to earth pressure shield in terms of ground subsidence control accuracy. But in recent ten years, many ground subsidence had happened caused by slurry shield machine construction operating under“giant thick rock”condition, diameter of shield machine was from 5 m to 15 m，even several of them led to huge economy lost and society impression.In view of the above problems, the author of this paper has found the main characteristics of such subsidence events through in-depth tracking, analyzing and researching of typical cases. (1) Shield machine was in fracture developed strata or mixed face ground with weathering slot or surface borehole locations; (2) Shield machine had appeared“clogging”or“claycake”before ground subsidence occurred; (3) Flush excavation chamber frequently was used in order to eliminate “clogging”as soon as possible and dredge slurry circulation lines, the result led to support pressure unstable. Based on this, the reasons and mechanism of ground subsidence caused by slurry shield construction under“giant thick rock”are deduced from geology, shield machine, construction technical measures and management, etc.Author answered the query comprehensively and on that basis, points out countermeasure suggestion for the reference of industry personnel.
ZHU Weibin1 MI Jinsheng1 XIE Wenda2 MENG Fanjing2
.Study on the Reasons and Countermeasure of Ground Subsidence Caused by Slurry Shield Construction Covered by a Giant Thick Rock Formation[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(6): 1-13
2022, Vol. 59 