黄原胶-粉煤灰联合处理酸污染土试验研究  

Experimental Study on Combined Xanthan Gum and Fly Ash Treatment on Acid-contaminated Soils

作　　者：倪静[1] 韩晓婷 贺青青 耿雪玉 NI Jing;HAN Xiao-ting;HE Qing-qing;GENG Xue-yu(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;College of Civil Engineering and Architecture,Wenzhou University,Wenzhou 325006,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]温州大学建筑工程学院,浙江温州325006

出　　处：《长江科学院院报》2024年第4期111-118,共8页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金项目(51978533,51608323)。

摘　　要：绿色环保型生物聚合物黄原胶应用于岩土工程,可提高土体强度及抗风蚀、水蚀能力。鉴于黄原胶分子中的丙酮酸基团和糖苷键在酸性土壤条件下易水解,导致凝胶黏性减小、固土效果减弱,拟采用碱性材料粉煤灰协同黄原胶固化酸污染土,并开展液塑限、击实及无侧限抗压强度试验。结果表明:粉煤灰有助于提高固化土的塑限、最优含水率及最大干密度。酸性土壤条件下,粉煤灰能明显改善黄原胶固土效果,联合法固化酸污染土强度甚至超过联合法固化未污染土。另外,粉煤灰可提高土壤的pH值,缓解黄原胶水解,使其发挥增黏及胶结土颗粒的作用。基于试验结果,建议采用联合法固化酸污染土(FA=9%,XG=3%),可比酸污染上海黏土强度提高310%;在未污染土中采用黄原胶即可(XG=4%),可比未污染天然上海黏土强度提高90%。研究成果有助于绿色环保型生物聚合物的推广与应用。Applying eco-friendly xanthan gum biopolymer(XG) in geotechnical engineering significantly enhances soil strength and boosts resistance against erosion from wind and water.The presence of pyruvate groups and glycosidic bonds in XG molecules leads to hydrolysis under acidic conditions,reducing the viscosity of XG hydrogels that bind soil particles.This study explores the effectiveness of using a combination of alkaline fly ash(FA) and XG to treat acid-contaminated soils through Atterberg limits,compaction,and unconfined compressive strength tests.The results demonstrate that FA contributes to increased plasticity limit,optimum moisture content,and maximum dry density,significantly enhancing the soil reinforcement capability of XG in acidic environments.The strength of acidcontaminated soils treated with this combined approach surpasses that of uncontaminated soils treated with the same approach.Moreover,FA mitigates the acidic soil conditions,preventing XG hydrolysis and enhancing soil treatment efficiency.Our findings recommend using a mixture of FA(9%) and XG(3%) for treating acid-contaminated soils,achieving a 310% strength increase compared to untreated soils.For uncontaminated soils,using XG alone(4%) results in a 90% strength improvement over untreated soils.

关 键 词：酸污染土 黄原胶 粉煤灰 界限含水率 击实 无侧限抗压强度 

分 类 号：TU411[建筑科学—岩土工程]