IMPACT OF POSTPONED WATER FEEDING TIME ON THE INFILTRATION-REDUCING EFFECT OF CEMENT INTO ALLUVIAL SOILS

摘要

Based on a series of indoor simulating infiltration tests, which experienced different postponed water feeding times after fine particulate matters infiltrating into the river alluvial sandy soils, the impact of postponed water feeding time to infiltration-reducing in the case of cement infiltrating into alluvial soils is revealed, and its mechanism is explained as well. The results show preliminarily that (1) compared to the method of instant water feeding after cement infiltrating into the riverbed alluvial soil, the method of postponed water feeding may enhance the infiltration-reducing effect 2 4 times on both tap water and sewage infiltration process, and extending the postponed time can enhance infiltration-reducing effect; (2) the infiltration-reducing rate is exponentially positive correlated to the postponed time and the reducing effect reaches to an ideal level when the postponed time rises to 12 h; however, the reducing effect is not obvious any more when the time is exceeding 24 h, especially for exceeding 36 h; (3) the trend of the infiltration-reducing rate changing is consistent after cement infiltrating into different textures of alluvial soil, yet, the postponed time that different soils reach to the ideal reducing effect is not the same. The results may provide a useful reference for the study of cutting pollutants migrating into the groundwater through surface water infiltration.