| The swelling index of some typical soils on Loess Plateau was measured to probe into the influence of soil texture, soil organic matter, soil bulk density, Ca2+, and intensity and frequency of ADW (Alternative Drying and Wetting) on soil swelling rate and soil structure. The results showed that the content of clay particles was significantly correlated with soil swelling rate. The content of soil organic matter affected soil swelling rate remarkably when soil texture was not obviously different. With the increase of soil bulk density, soil swelling rate was increased by 1.70%~30.22%. Ca2+ showed crucial restraint to soil swelling rate. The intensity of ADW affected soil swelling rate, and the swelling rate of the soil dried at 40℃ was higher than that dried at 30℃, with an increase rate of 30.28%81.20%. The frequency of ADW also affected soil swelling rate. The soil swelling rate was raised when the frequency was increased, and the effect was most remarkable in the first time of ADW. |