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| PREDICTION OF SWCC FOR UNSATURATED CRACKED SOIL CONSIDERING DEVELOPMENT PROCESS OF CRACKS |
| LI Jinhui1，GUO Lingbo2，ZHANG Limin3 |
| (1. Department of Civil and Environmental Engineering，Shenzhen Graduate School，Harbin Institute of Technology，Shenzhen，Guangdong 518055，China；2. Huasen Architectural and Engineering Designing Consultant Ltd.，Shenzhen，Guangdong 518054，China；3. Department of Civil and Environmental Engineering，The Hong Kong University of Science and Technology，Kowloon，Hong Kong，China) |
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Abstract Cracks are widely presented in natural and engineered soils. Cracks provide preferential pathways for water flow and significantly increase the hydraulic conductivity of the soil mass. The soil-water characteristic curve(SWCC) for the cracked soil is a key factor in seepage analysis. This paper presents a new method to predict the SWCC for a cracked soil considering the crack development process during drying-wetting cycles. The cracked soil is divided into a crack network system and a soil matrix system. The SWCC for the cracked soil at a specified crack state can be obtained by combining the estimated SWCCs for the two pore systems. Then，the SWCCs for the cracked soil at different crack states along a crack development path can be obtained and combined to give the SWCC for the cracked soil considering the crack development process. The dynamic development of cracks in a soil specimen during drying and wetting and its drying SWCC are also measured in the laboratory. The SWCC for the cracked soil considering the crack development is predicted. The predicted results are verified by test results. The SWCC for the cracked soil shows bimodal features. At low matrix suctions，the SWCC is mainly controlled by the crack network. When the matrix suction is larger than the air-entry value of the soil，the SWCC is mainly controlled by the soil matrix suction.
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Received: 14 January 2013
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2013, Vol. 32 
