SWCC model for double-pore structured unsaturated clay

CAI Guo-qing; HAN Bo-wen; WANG Ya-nan; JIANG Tian; XIE Lin; ZHANG Ce

doi:10.11779/CJGE2022S1001

Volume 44 Issue S1

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Chinese Journal of Geotechnical Engineering > 2022 > 44(S1): 1-5. > DOI: 10.11779/CJGE2022S1001

CAI Guo-qing, HAN Bo-wen, WANG Ya-nan, JIANG Tian, XIE Lin, ZHANG Ce. SWCC model for double-pore structured unsaturated clay[J]. Chinese Journal of Geotechnical Engineering, 2022, 44(S1): 1-5. DOI: 10.11779/CJGE2022S1001

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SWCC model for double-pore structured unsaturated clay

1.
Key Laboratory of Urban Underground Engineering of Ministry of Education, Beijing 100044, China
2.
School of Civil Engineering and Architecture, Beijing JiaoTong University, Beijing 100044, China
3.
Henan Provincial Department of Transportation, Zhengzhou 450003, China

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Received Date: September 24, 2022
Available Online: February 06, 2023

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Abstract

Abstract

Some mercury intrusion test results show that the soils using the compaction sample preparation method usually present a typical double-pore micro structure, while the existing unsaturated SWCC models are mostly directed to single-pore structural soils. In order to reflect the double-pore structure inside the soils and the joint effects of deformation on water-holding performance, a unsaturated SWCC model for the double-pore structure considering deformation is proposed and verified through experiments. The "junction point" in the double-pore SWCC is regarded as the boundary point of different pore sizes of the double-pore structured unsaturated soils, and equations for the SWCC of different sections are established. The parameter is introduced in the segment equation to reflect the influences of the deformation. According to the compacted samples of Guilin lateritic clay, the SWCC tests in the full suction range are carried out based on the shaft translation technique, the filter paper method and the saturated salt solution steam balance method. The model parameters are calibrated, and the proposed model is verified.
- unsaturated soil,
- soil-water characteristic curve,
- double porosity soil,
- deformation,
- junction point

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References (17)

References

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