Model experimental study on gas migration and reinforcement mechanism of air-booster vacuum preloading#br#
LIU Jingjin1，2，LI Jiankai1，LEI Huayang1，2
(1. Department of Civil Engineering，Tianjin University，Tianjin 300354，China；2. Key Laboratory of Coast Civil Structure Safety of Ministry of Education，Tianjin University，Tianjin 300354，China)
Abstract：At present，the academic circles have different understanding of the gas migration path after gas injection operation and reinforcement mechanism of air-booster vacuum preloading. In view of this problem，several groups of air-booster vacuum preloading model experiments were designed to explore the gas migration path after gas injection operation and reinforcement mechanism of air-booster vacuum preloading. By comparing and analyzing the test results of drainage，pore water pressure，settlement，vane shear strength and water content，the following conclusions were obtained：in the process of treating ultra-soft soil by air-booster vacuum preloading，the gas moves to the soil surface first after gas injection. At the same time，by considering the real-time pore pressure change during gas injection operation，it is speculated that the main mechanism of gas injection operation to improve the drainage and consolidation effect of soil is as follows：during gas injection operation，the rise of pressurized gas will drive the deep pore water to migrate to the shallow layer，so that the deep pore water can be quickly absorbed and discharged by the drainage plate in the shallow layer，so as to improve the reinforcement effect of deep soil and the overall drainage efficiency.
刘景锦1，2，李建楷1，雷华阳1，2. 增压式真空预压气体运移加固机制模型试验研究[J]. 岩石力学与工程学报, 2023, 42(S1): 3598-3608.
LIU Jingjin1，2，LI Jiankai1，LEI Huayang1，2. Model experimental study on gas migration and reinforcement mechanism of air-booster vacuum preloading#br#. , 2023, 42(S1): 3598-3608.
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2023, Vol. 42 
