Experimental study and numerical simulation of an alternating vacuum preloading method for strengthening hydraulic fill super soft soils#br#
LEI Huayang1,2,LI Chenyuan1,LIU Jingjin1,2,WANG Lei1
(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:Drainage plate clogging often results in poor reinforcement effect of the conventional vacuum preloading technology applied to hydraulic fill super soft soil grounds. To solve the problem,a new type of vacuum preloading method,namely alternating vacuum preloading method,for treating hydraulic fill super soft soils,was proposed,and the reinforcement mechanism and effect were investigated based on the indoor model test and numerical simulation of PFC2D. The study results show that the alternating movement of soil particles due to the alternating vacuum preloading can effectively prevent the formation of clogging mud layers and“soil columns”and hence,make the overall reinforcement more uniform and effective. It is also shown that,compared with the conventional vacuum preloading method,the water discharge and the settlement of the soil ground reinforced by the proposed method increase by 14.92% and 11.80% respectively,the vane shear strength of the reinforced soil rises by 21.65% and the water content reduces by 26.74%. The compaction degree of the clogging mud layer decreases while the porosity of the clogging mud layer increases by more than 30%,which indicates that the anti-clogging effect of the developed method is obvious.
雷华阳1,2,李宸元1,刘景锦1,2,王 磊1. 交替式真空预压法加固吹填超软土试验及数值模拟研究[J]. 岩石力学与工程学报, 2019, 38(10): 2112-2125.
LEI Huayang1,2,LI Chenyuan1,LIU Jingjin1,2,WANG Lei1. Experimental study and numerical simulation of an alternating vacuum preloading method for strengthening hydraulic fill super soft soils#br#. , 2019, 38(10): 2112-2125.
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