针对花岗岩残积土遇水易软化、崩解的特性,通过干湿循环下花岗岩残积土的崩解试验,研究了花岗岩残积土的压实度和干湿循环次数对其崩解特性和崩解参数指标的影响。得到以下结论:花岗岩残积土的压实度越小、经历的干湿循环次数越多,崩解速率越快,试样完全崩解所需的时间越短;拟合了平均崩解速率与干湿循环次数、压实度之间的函数关系式。利用电镜扫描试验,分析干湿循环作用下花岗岩残积土的微观结构变化,解释了崩解机理:随着干湿循环次数增加,片状颗粒间的层叠结构遭到破坏,颗粒的团聚性减弱,平面孔隙率增大,结构趋向疏松,加速了花岗岩残积土的崩解。
Abstract
Granite residual soil is prone to soften and disintegrate in contact with water.The effects of compactness and number of dry-wet cycles on the disintegration characteristics and disintegration indexes of granite residual soil were examined via disintegration test under dry-wet cycles.Results demonstrated that the smaller degree of compaction and the more times of dry-wet cycles,the faster the disintegration and the shorter the time required for the sample to completely disintegrate.The functional relations of average disintegration rate against number of dry-wet cycles and degree of compaction were fitted.The microstructure change of granite residual soil under dry-wet cycle was obtained by scanning electron microscope test.The micro-mechanism of disintegration was explained:with the number of dry-wet cycles increased,the lamellar structure of flake particles was destroyed,the agglomeration of particles was weakened,the plane porosity increased,and the structure tended to loose,which accelerated the disintegration of granite residual soil.
关键词
花岗岩残积土 /
干湿循环 /
压实度 /
崩解 /
扫描电镜
Key words
granite residual soil /
dry-wet cycle /
degree of compaction /
disintegration /
scanning electron microscope
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 李善梅,吴 孟,蒙剑坪,等.压实度与初始含水率对红黏土崩解特性的影响[J].河南科技大学学报(自然科学版),2021,42(4):54-59.
[2] 尹 松,白林杰,李新明,等.压实花岗岩残积土的崩解特性试验研究[J].长江科学院院报,2021,38(9):121-127.
[3] 李家春,崔世富,田伟平.公路边坡降雨侵蚀特征及土的崩解试验[J].长安大学学报(自然科学版),2007,27(1):23-26,49.
[4] CHAN K Y,MULLINS C E.Slaking Characteristics of Some Australian and British Soils[J].European Journal of Soil Science,1994,45(3):273-283.
[5] 张先伟,孔令伟,陈 成,等.炎热多雨和突降暴雨气候影响下玄武岩残积土的崩解试验研究[J].中国科学(技术科学),2016,46(11):1175-1184.
[6] 柴肇云,张亚涛,张学尧.泥岩耐崩解性与矿物组成相关性的试验研究[J].煤炭学报,2015,40(5):1188-1193.
[7] 张 抒,唐辉明.非饱和花岗岩残积土崩解机制试验研究[J].岩土力学,2013,34(6):1668-1674.
[8] 吴能森.花岗岩残积土的崩解性及软化损伤参数研究[J].河北建筑科技学院学报,2006,23(3):58-62.
[9] 王幼麟,蒋顺清.葛洲坝工程某些粉砂岩软化和崩解的微观特性[J].岩石力学与工程学报,1990,9(1):48-57.
[10]兰泽鑫.花岗岩残积土崩解试验研究[D].广州:华南理工大学,2013.
[11]吴 文.干湿循环下花岗岩残积土特性试验研究[D].南昌:南昌大学,2018.
[12]刘文骏,陈秋南,赵磊军,等.水泥改良花岗岩残积土的强度和崩解特性研究[J].湖南科技大学学报(自然科学版),2016,31(1):54-59.
[13]COLLINS K,MCGOWN A.The Form and Function of Microfabric Features in a Variety of Natural Soils[J].Geotechnique,1974,24(2):223-254.
[14]MITCHELL J K.岩土工程土性分析原理[M].高国瑞,译.南京:南京工学院出版社,1988.
[15]孔令伟,吕海波,汪 稔,等.海口某海域软土工程特性的微观机制浅析[J].岩土力学,2002,23(1):36-40.
[16]施 斌.粘性土微观结构简易定量分析法[J].水文地
质工程地质,1997,24(1):7-10.
[17]李中森,汤连生,桑海涛.花岗岩残积土颗粒及水分形态三维微观结构[J].中山大学学报(自然科学版),2017,56(6):15-21.
[18]杨鹏飞,李 显,阙 云,等.RVE孔隙模型细观结构特征分析与对比[J].长江科学院院报,2022,39(8):99-104.
[19]周翠英,景兴达,刘 镇.华南红层风化土崩解特性及其改性研究[J].工程地质学报,2019,27(6):1253-1261.
[20]曾 朋.花岗岩残积土的压实特性及崩解特性研究[D].广州:华南理工大学,2012.
基金
厦门市交通基础设施智能管养工程技术研究中心开放基金项目(TCIMI201804)