闽南砂性填料土水特征曲线的滤纸法试验研究

针对闽南地区典型砂性土填料，采用滤纸法试验测定滤纸含水率与平衡土体含水率，根据滤纸率定方程计算出土体基质吸力；进而采用三种数学模型拟合试验数据，选取最适合的V-G模型拟合得到其基质吸力的土水特征曲线。研究表明:同一干密度下，基质吸力随体积含水率下降而增大，初始增速缓慢，但随着含水率减小，基质吸力显著增大。由于闽南地区砂性土填料持水能力较弱，在设计时可考虑基质吸力引起的附加剪切强度以增大地基承载力，维持边坡稳定性。

Experimental Study on Soil-water Characteristic Curve of Sandy Soil Filler in South Fujian by Filter Paper Method

For typical sandy soil filler in south Fujian area, filter paper test method was used to find the water content of filter paper and soil mass in equilibrium state, and then the matric suction of soil mass was calculated by the calibration equation of filter paper; furthermore, the test data fitting was carried out by use of three mathematical models, wherein the V-G model most appropriate was selected to get the soil-water characteristic curve of matric suction by fitting. The study shows that, under the same dry density, the matric suction increases with the decrease of volume water content slowly at first, but rapidly as the water content reduces. The water holding capacity of sandy soil filler in south Fujian is so weak that the additional shear strength caused by the matric suction may be taken into consideration in design to improve the bearing capacity of foundation and maintain the stability of slope.