华东地质2026，Vol.47Issue(3)：476-485,10.DOI:10.16788/j.hddz.32-1865/P.2024.10.002
滇东竹园地区沉积型膨胀土的发育特征及工程特性
Development characteristics and engineering properties of sedimentary expan-sive soil in the Zhuyuan area,Eastern Yunnan
摘要
Abstract
This study employs multiple methodologies including field investigation,geophysical exploration,shallow well engineering operations,and laboratory analysis to examine the development characteristics and engi-neering geological properties of expansive soil in the Zhuyuan area of Eastern Yunnan.The findings reveal that the sedimentary expansive soil in the Zhuyuan area primarily occurs in the upper Neogene Ciying Formation(N2c),with its distribution significantly controlled by faults systems.From the perspective of material composi-tion,expansive soil predominantly consists of quartz and clay minerals,with notable proportions of feldspar and gypsum.In terms of engineering characteristics,the expansive soil in this area has challenging properties includ-ing high dispersibility,high plasticity,and high porosity.The soil presents clay content ranging from 22.0%to 69.1%,liquid limit from 38.1 to 63.0,plastic limit from 20.4 to 36.9,plasticity index from 14.8 to 26.1,and natu-ral porosity ratios predominantly approaching 1,with maximum values reaching 1.51.The free expansion rate ranges from 33-65,classifying it as weak expansive soil.Microstructural analysis indicates that the primary clay minerals comprise curved sheet-like illite/montmorillonite mixed layers.The microstructure exhibits a"face edge"configuration with well-developed interlayer micropores,facilitating water migration and wet swelling and drying shrinkage process.These adverse engineering geological characteristics of sedimentary expansive soil in the Zhuyuan area constitute the primary factors contributing to frequent geological disasters in the region.Conse-quently,geological disaster prevention and control efforts must thoroughly consider the engineering geological characteristics of expansive soil,particularly the influence of hydrodynamic forces.The implementation of com-prehensive prevention measures including drainage systems,support structures,and slope protection,is essential for management of these geological challenges.关键词
膨胀土/发育特征/工程特性/滇东地区Key words
expansive soil/development characteristics/engineering property/Eastern Yunnan分类
天文与地球科学引用本文复制引用
陶兰初,朱星强,陈超,马一奇,寸得欣,邹石林,和成忠,张七道..滇东竹园地区沉积型膨胀土的发育特征及工程特性[J].华东地质,2026,47(3):476-485,10.基金项目
中国地质调查局"全国国土变更调查国家级外业核查(昆明中心)(编号:DD20230526)""川滇生态屏障重点地区生态修复综合调查(编号:DD20230098)""滇西北高山峡谷区生态修复综合调查(编号:DD20230483)"项目联合资助. （昆明中心）
