期刊论文

Swelling Characteristics and Microscopical Analysis of Expansive Soil Under Dry-wet Cycles in Acid Environment

Xiao, J.

中文

中国公路学报

1001-7372

2019

32

3

34-43

10.19721/j.cnki.1001-7372.2019.03.004

国家自然科学基金项目(51608053) 湖南省自然科学基金项目(2017JJ3335) 湖南省研究生科研创新项目(CX2017B458).

本校为第一且通讯机构

弄清酸雨及干湿循环共同作用下膨胀土的膨胀性能及其微结构与矿物成分的变化,对研究酸雨区膨胀土的基本性质劣化及工程问题意义重大。为此,以广西酸雨重灾区百色原状膨胀土为对象,模拟酸雨(pH=3,5,7)与干湿循环(n=1,2,3,4)两者共同作用的环境,开展了无、有荷膨胀率试验,并采用扫描电镜(SEM)、压汞仪(MIP)和X射线衍射仪(XRD)分析了该环境下试样的微结构及矿物成分的演变规律。研究结果表明:酸性环境使试样的膨胀率增大,溶液的pH值越小,膨胀率越大;随干湿循环作用次数的增加,不同溶液环境下试样的膨胀率均先增大后趋于稳定,且2次作用后的增幅最大;经酸性环境与干湿循环共同作用试样的膨胀率增大更...

The expansion properties of expansive soils and their microstructure and mineral composition are significantly affected by the combined effects of acid rain and dry-wet cycles. It is, therefore, of utmost importance to study the deterioration of their basic properties and subsequent engineering problems in areas of acid rain. For this purpose, Baise expansive soil from the heavy acid rain area of Guangxi was selected as the target sample. The coupled effects of acid rain (pH=3, 5, 7) and dry-wet cycle (n=1, 2, 3, 4) on expansion properties of e...