含粉砂层软土地基真空预压密封性及现场试验研究

doi:10.13722/j.cnki.jrme.2023.1247

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Abstract When using vacuum preloading for soft soil foundations that contain high permeability sand layers，it is effective to establish a clay sealing wall to maintain the integrity of the vacuum system. The silt mixed with silt forms a flocculent structure at a microscopic level，which significantly affects the soil permeability when subjected to external disturbance. Experiments were conducted to determine the relationship between soil permeability coefficient(kv)，effective stress(?′)，and clay content(Nc). This relationship can be used as a basis for evaluating the construction of sealing walls. Subsequently，field tests were conducted on this type of foundation with different PVD spacing. The test results revealed that the permeability coefficient of silty sand and silt is less than 10－5 cm/s，considering the effect of ?′. The vacuum pressure under the membrane was maintained at around 83 kPa，indicating good sealing performance of the vacuum system and suggesting that a sealing wall is unnecessary for this type of foundation. After reinforcement，the moisture content is reduced by 20% and the void ratio of silt is reduced by 30%. The vane shear strength increased by 22.3–32.23 kPa.

Key words： foundation silty sand mixed with silt vacuum preloading sealing performance field test PVD spacing

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	FU Hongtao1
	2
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	4
	WANG Xiaofeng1
	WEN Zuojia1
	GAO Ziyang1
	2
	5
	WANG Jun1
	2
	3
	4
	LI Xiaobing1
	2
	3
	4
	YE Shuxiang6
	LIN Zhongzhe6

Cite this article:

FU Hongtao1,2,3, et al. Vacuum preloading sealing performance and field test of soft soil foundations with silty sand layer[J]. , 2024, 43(10): 2581-2589.

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https://rockmech.whrsm.ac.cn/EN/10.13722/j.cnki.jrme.2023.1247 OR https://rockmech.whrsm.ac.cn/EN/Y2024/V43/I10/2581

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