(1. Institute of Rock and Soil Mechanics，Chinese Academy of Sciences，Wuhan，Hubei 430071，China；2. College of Urban Construction，Wuhan University of Science and Technology，Wuhan，Hubei 430081，China；
3. School of Civil Engineering，Tongji University，Shanghai 200092，China)
Abstract：In order to study the effects of dry density and initial water content on water retention of coral sand，soil-water characteristic curves of samples with different dry densities and initial water contents were tested and analyzed by pressure plate apparatus test，and the pore water distribution characteristics of samples under different suction forces were obtained by nuclear magnetic resonance technology. The results show that the air entry value of coral sand increases with the increase of dry density and decreases with the increase of initial water content. The residual water content increases with the increase of dry density and initial water content. In general，the samples with high dry density and initial water content have better water retention. The F‐X model has good applicability to soil-water characteristic curves of coral sand samples under different conditions. Dry density and initial water content have important effects on pore size distribution and water retention of compacted coral sand samples，but their effects on water retention gradually weaken with the increase of matric suction. At different suction stages，the effects of dry density and initial water content on water retention of coral sand were different. At 0–10 kPa，the initial water content was the main factor，while at 10–70 kPa，the dry density had a greater effect，and at 70–300 kPa，neither of them had a major effect on water retention of coral sand. The poor connectivity of coral sand pores results in large pores that can still store water under high suction，which enhances the water retention of coral sand to a certain extent.
吴 昊1，2，沈建华1，雷学文2，陈 翔3，丁浩桢1，王新志1. 干密度和初始含水率对珊瑚砂持水性的影响研究[J]. 岩石力学与工程学报, 2024, 43(S1): 3568-3577.
WU Hao1，2，SHEN Jianhua1，LEI Xuewen2，CHEN Xiang3，DING Haozhen1，WANG Xinzhi1. Effects of dry density and initial water content on water retention of coral sand. , 2024, 43(S1): 3568-3577.
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2024, Vol. 43 
