阿拉伯树胶改性预崩解炭质泥岩路用性能及改性机制  

Road Performance and Modification Mechanisms of Disintegrated Carbonaceous Mudstone Modified with Gum Arabic

作　　者：曾铃[1,2] 余慧聪 高乾丰 查焕奕 祖宇轩 卞汉兵 ZENG Ling;YU Hui-cong;GAO Qian-feng;ZHA Huan-yi;ZU Yu-xuan;BIAN Han-bing(Key Laboratory of Bridge Engineering Safety Control by Department of Education,Changsha University of Science&Technology,Changsha 410114,Hunan,China;School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;School of Traffic&Transportation Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;International College of Engineering,Changsha University of Science&Technology,Changsha 410114,Hunan,China;Laboratoire de Génie Civil et Géo-environnement,Universitéde Lille,Lille 59000,Nord,France)

机构地区：[1]长沙理工大学桥梁工程安全控制教育部重点实验室,湖南长沙410114 [2]长沙理工大学土木工程学院,湖南长沙410114 [3]长沙理工大学交通运输工程学院,湖南长沙410114 [4]长沙理工大学国际工学院,湖南长沙410114 [5]里尔大学土木工程与岩土环境工程实验室,诺尔里尔59000

出　　处：《中国公路学报》2023年第10期42-54,共13页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(52078067,52078066,51838001,52008041);湖湘青年科技创新人才项目(2020RC306);长沙市杰出创新青年培养计划项目(kq2206030);湖南省自然科学基金项目(2021JJ40576,2023JJ10045);桥梁工程安全控制教育部重点实验室开放基金项目(15KB01);湖南省研究生科研创新项目(CX20230874)。

摘　　要：为提升预崩解炭质泥岩路用性能以用作路堤填料,采用阿拉伯树胶对预崩解炭质泥岩进行改性,分析改性后预崩解炭质泥岩的路用性能及改性机制。开展加州承载比(CBR)、回弹模量、无侧限抗压强度(UCS)及单轴抗拉强度试验,研究阿拉伯树胶掺量与养护龄期对改性预崩解炭质泥岩路用性能的影响,并通过崩解性、酸碱度(pH)、电导率、溶解性固体总量(TDS)及Zeta电位试验分析改性前后预崩解炭质泥岩理化特性的变化,结合扫描电镜(SEM)、X射线能谱分析(EDS)与傅里叶变换红外光谱分析(FTIR),探讨阿拉伯树胶对预崩解炭质泥岩的改性机制。研究结果表明:阿拉伯树胶能有效改善预崩解炭质泥岩的路用性能,且随掺量与养护龄期增加,路用性能改善程度逐渐增大;结合经济性考虑,阿拉伯树胶掺量为4%时路用性能改性效果最佳,CBR与回弹模量分别提升495%和427%,UCS与单轴抗拉强度均提升230%以上;掺入阿拉伯树胶可大幅降低预崩解炭质泥岩的崩解率、pH值、电导率、TDS及Zeta电位绝对值,改善预崩解炭质泥岩的水稳性;阿拉伯树胶通过降低预崩解炭质泥岩碱性、提供阳离子与颗粒表面离子发生离子交换并吸附在颗粒表面的方式,优化改性预崩解炭质泥岩内部结构性,通过胶结预崩解炭质泥岩颗粒、填充内部孔洞与孔隙的方式提升黏聚力与整体性,并包覆在颗粒与团聚体表层,阻隔外部环境直接作用。研究结果可为预崩解炭质泥岩再利用提供思路,并为阿拉伯树胶用作其他岩土材料的改性剂提供参考。The aim of this study is to improve the road performance of disintegrated carbonaceous mudstone,enabling it to qualify as an embankment filler.For this purpose,disintegrated carbonaceous mudstone was modified with gum arabic,and the road performance of the modified disintegrated carbonaceous mudstone and its modification mechanisms were analyzed.The effects of the gum arabic content and curing duration on the road performance were examined using the California bearing ratio(CBR),resilient modulus,unconfined compressive strength(UCS),and uniaxial tensile test.The physicochemical property changes of the disintegrated carbonaceous mudstone before and after modification were analyzed by measuring the disintegration,pH,conductivity,total dissolved solids,and zeta potential.The mechanism by which the gum arabic modified the disintegrated carbonaceous mudstone was explored using scanning electron microscopy,X-ray energy dispersive spectroscopy,and Fourier-transform infrared spectroscopy.The results of the study show that gum arabic effectively improves the road performance of disintegrated carbonaceous mudstone,and the degree of improvement gradually increases with increasing dosages and maintenance age.From an economic perspective,the best modification effect on road performance is achieved when the gum arabic dosage is 4%at which point the CBR and resilient modulus increase by 495%and 427%,respectively,and the UCS and uniaxial tensile strength increase by more than 230%.Gum arabic significantly reduces the disintegration rate,pH,conductivity,TDS,and absolute zeta potential of disintegrated carbonaceous mudstone,thereby improving its water stability.Moreover,the internal structure of the modified disintegrated carbonaceous mudstone is optimized by reducing its alkalinity,thus facilitating ion exchange between the cations and ions on the particle surfaces.Furthermore,the cohesion and integrity improve through the cementing of disintegrated carbonaceous mudstone particles,filling of internal pores,and encapsulation of su

关 键 词：路基工程 预崩解炭质泥岩 试验研究 路用性能 阿拉伯树胶 改性机制 

分 类 号：U416.1[交通运输工程—道路与铁道工程]