不同干密度对兰州地区黄土毛细吸水影响的试验研究

Experimental Study on Effects of Different Dry Density on Capillary Water Absorption of Loess in Lanzhou Gansu Province

以甘肃省兰州市青白石乡的黄土为研究对象,通过对3组相同含水率,不同干密度(1.5,1.6,1.7)下的重塑试样进行毛细吸水试验,研究了干密度对毛细吸水的影响。研究发现:干密度越大,毛细吸水速率越慢,水分到达顶端需要的时间越长;试样底部的含水率最高,在26%~30%之间,含水率沿着试样向上逐渐降低,在试样中部4 cm处出现明显变化,0~4 cm含水率变化幅度大,4~8 cm含水率变化幅度小,说明毛细作用主要集中在试样的中下部分;在相同初始含水率条件下,干密度越小,毛细作用越明显。

In order to investigate the influence of capillary water absorption by different dry density,we conduct free capillary water absorption test by using 3 different dry density（1. 5,1. 6,1. 7） remodeled loess which from Qingbaishi village,Lanzhou,Gansu province. Research shows that：（1） The greater the dry density,the slower the capillary water absorption rate,and the longer it takes for the moisture to reach the top;（2） The moisture content of the sample at the bottom of the sample is the highest,between 26 % - 30 %,the moisture content along the sample gradually decreased,at the middle of the sample 4 cm significant changes,0 - 4 cm water content changes is large,the rate of change is small at 4 - 8 cm. Indicating that the capillary effect is mainly concentrated in the middle and lower part of the sample;（3） Under the same initial moisture content,the smaller the dry density,the more obvious the capillary effect.