doi:10.16186/j.cnki.1673-9787.2020.5.22

Received:2019/12/08

Revised:2020/02/20

Published:2020/09/15

Laboratory experimental study on industrial alkali residue-modified expansive soil

SUN Xiaohai, XIE Jianbin, ZHAO Yijin, CHEN Wei, ZHANG Wenhao, JIANG Sheng

School of Architecture and Urban Planning， Yunnan University， Kunming 650500 ， Yunnan， China

Abstract:In order to verify the effect of industrial alkali residue on improved typical expansive soil in Mengzi area of Yunnan Province， the basic characteristics of expansive soil under different admixture ratios of cement， industrial alkali residue and cement + industrial alkali residue were discussed by way of comparative tests. The improved expansive soil was generally through lime， cement， gravel and so on， and the application of industrial alkali residue in the improvement of expansive soil was rare. Laboratory test were adopted to study on improving of typical expansive soil in Mengzi area of Yunnan Province industrial alkali residue. By controlling different cement amount， industrial alkali residue amount， cement + industry alkali residue amount， the variation of basic characteristics of expansive soil were studied. The test results show ： Industrial alkali residue reduced the free expansion rate of pure expansive soil from 71% to about 18% ， and the minimum expansion rate of industrial alkali residue modified soil was only 0.75 times of that of cement modified soil. Industrial alkali residue， cement， cement + industry alkali residue all could improve the grading curve of expansive soil， and the effect of industrial alkali residue at the ratio of 30% was the most obvious. When the ratio of industrial alkali residue was 40% ， the plastic limit of pure expansive soil increased from 23% to 37% ， the liquid limit decreased from 64% to about 42% ， and the plasticity index decreased from 41.6 to 5.3.With the increase of the admixture ratio of industrial alkali residue， the maximum dry density decreased gradually， and the optimum moisture content decreased first and then increased. When the mixing ratio was 30% ， the maximum dry density and the optimal moisture content reached the optimal values.

Key words:typical expansive soil in Yunnan Province;industrial alkali residue;free expansion rate;liquid lim

工业碱渣改性膨胀土室内试验研究_孙孝海.pdf