基于颗分曲线预测可降解土体土水特征曲线的初探研究

可降解土体的土水特征曲线测试较复杂，文中改进了Arya-Paris模型，通过颗分曲线和孔隙比来预测土体的土水特征曲线，获得的微分形式的计算模型能够应用颗分曲线的连续表达公式预测土水特征曲线，避免了人为划分颗分曲线进行计算带来的较大偏差|针对可降解土体，提出指数形式的颗分曲线计算模型描述降解过程中固相颗粒粒径的衰变。利用上述改进后的土水特征曲线预测模型和可降解土体的颗分曲线计算模型，基于不同龄期城市固废钻孔样颗分曲线的实测数据，对不同龄期城市固废钻孔样的土水特征曲线进行了预测。通过与实测结果对比发现，预测结果能够较好的反映降解引起城市固废持水特性衰变的总体规律，即城市固废持水能力随着龄期的增大而增加。文中理论工作为研究其他类型可降解土体（不同降解模式）持水特性衰变规律奠定了一定基础。

Prediction on the soil-water characteristic curve of degradable soil from particle-size distribution curve

Testing soil-water characteristic curve (SWCC) of degradable soil is rather complex. The Arya-Paris model was modified to predict SWCC of degradable soil from particle-size distribution (PSD) curve and void ratio. The modified model expressed in the differential form could use continuous PSD data, and hence avoid the prediction error caused by artificial division of PSD curve. An exponential model describing the changing of PSD with degradation time was established for degradable soil. Based on the above models, SWCCs of borehole municipal solid waste (MSW) specimens were predicted from the tested PSD curves. The comparison between predicted and tested SWCCs indicated that the proposed models could capture the changing behavior of SWCC with degradation for MSW: higher water retention capacity for the MSW with larger fill age. The theoretical work in this study would be helpful for studying the changing behavior of SWCC for other kinds of degradable soil.