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研究石膏含量为 64 %的压实石膏土长期浸水对加利弗尼亚承重系数 (CBR)的影响。依据ASTM(D1 883 -87)规范 ,准备 1 6个以最优含水量压实到AASHTO干密度的 95 %的试样。分为两组 ,每一组在 89N超载负荷下分别浸水 0 ,4,7,1 5 ,3 0 ,60 ,1 2 0 ,1 80d。浸水池中的水要不断更换以避免石膏过饱和。试验显示CBR在浸水期间急剧减小 ,第一个星期尤为明显。之后CBR以较小的速度减小 ,直到 6个月以后土壤强度趋于恒定。随着浸水时间的延续 ,土壤中总的溶性盐和石膏成分的减少与浸水期间CBR的减小完全一致。研究表明 ,4d的浸水时间对此类土壤来说 ,会导致土壤强度值估算过高
The effect of long-term flooding of compacted gypsum soil with a gypsum content of 64% on the load-bearing coefficient of California (CBR) was studied. According to the ASTM (D1 883-87) specification, 16 samples of 95% compacted to the dry density of AASHTO at the optimum moisture content were prepared. Divided into two groups, each group were immersed in 0, 4, 7, 15, 30, 60, 120, 180d under an overload of 89N. The water in the sink should be changed to prevent the gypsum from over-saturating. Trials have shown that CBR drastically decreases during flooding, especially in the first week. The CBR then decreases at a slower rate until the soil strength tends to be constant after 6 months. As the immersion time continues, the reduction of total dissolved salts and gypsum components in the soil is exactly the same as the decrease of CBR during immersion. Studies have shown that immersion time of 4 days can lead to over-estimation of soil strength values for such soils