论文部分内容阅读
滤纸法是一种间接测量非饱和土吸力的测量方法,在用滤纸测定土壤吸力之前需获得能够表达吸力与滤纸含水率之间关系的率定曲线。国内外的研究人员对Whatman No.42、Schleicher&Schuell No.589和国产“双圈”牌定量滤纸的率定曲线已有研究,但是考虑到温度效应的滤纸率定曲线研究还有待深入。采用不同摩尔浓度的Na Cl溶液测定了国产双圈203滤纸分别在20℃、25℃、30℃、40℃下的滤纸吸湿过程的率定曲线,结果表明滤纸的持水性随着温度的升高而降低,且温度对低吸力段滤纸持水性能的影响要高于高吸力段。通过多元线性回归分析建立了考虑温度效应的率定方程,通过微观结构观测和表面物理化学理论分析了温度对率定曲线影响机制。
Filter paper method is a indirect measurement of unsaturated soil suction measurement method, before using the filter paper to determine the soil suction required to be able to express the relationship between suction and filter paper rate curve. Researchers at home and abroad have studied the calibration curves of Whatman No.42, Schleicher & Schuell No.589 and domestic “double circle” brand quantitative filter paper, but the study on the calibration curve of filter paper considering the temperature effect needs to be further studied. The calibration curves of the moisture absorption of filter paper in domestic double-circle 203 filter paper at 20 ℃, 25 ℃, 30 ℃ and 40 ℃ were measured by NaCl solution with different molar concentrations. The results showed that the water holding capacity of filter paper increased with the increase of temperature While the influence of temperature on the water holding capacity of filter paper with low suction is higher than that of high suction. Based on multivariate linear regression analysis, a rate-determining equation considering the temperature effect was established. The influence mechanism of temperature on the calibration curve was analyzed by microstructure observation and surface physico-chemical theory.