含水量对黄土震陷性定量影响研究

Study on the Influence of Water Content to Subsidence Characters of Loess

摘要:

含水量是影响黄土震陷性非常重要的参数。本文以洮河三级阶地上典型的Q3黄土为研究对象,对其震陷性特征进行了全面、系统的研究。通过在20 m深探井中依次取得4 m、8 m、12 m、16 m、20 m处黄土原状试样进行室内试验,得到以下结果:(1)天然黄土存在震陷性随深度增加而逐渐减弱的规律;(2)通过增湿、减湿获得5%,10%,15%和20%四种不同含水量黄土试样,同一深度黄土随着含水量增加其震陷性增长的规律明显;(3)通过实验数据分析得到了含水量对黄土震陷性定量影响规律,并根据其规律给出了不同动应力作用下的黄土震陷临界含水量。

Abstract:

Water content of loess is a very important parameter for seismic subsidence.The subsidence characters of the typical Q3 loess,located on third terrace of Tao River are systemically investigated.The samples taken at depth of 4 m,8 m,12 m,16 m,20 m in a 20 m depth pit are researched in laboratory.The results show some primary achievements：（1） the seismic subsidence capacity of natural loess gradually weakens with depth increasing;（2） there is a obvious law that the seismic subsidence capacity of loess increases with the growth of water content in same depth from experimenting 4 samples with 5%,10%,15% and 20% water content,which were acquired by humidification and dehumidification of the samples;（3）Through analyzing the experiment data,the quantitative law of water content influence on the seismic subsidence capacity of loess is found,and based on the law,the critical water contents of loess seismic subsidence are given under different dynamic stress.