超轻陶粒土的一维压缩特性及其微观机理  

Study on Physical and Mechanical Behavior of Granular Soil Composed of Ultra-Light-Weight Expansive Clay Aggregates

作　　者：葛晓永 徐玉桂 张军 王志华 申志福 GE Xiao-yong;XU Yu-gui;ZHANG Jun;WANG Zhi-hua;SHEN Zhi-fo(Nanjing Jiangbei New District Center Zone Development Co.Ltd.,Nanjing 211899,China;College of Transportation Science and Engineering,Nanjing Tech University,Nanjing 210009,China)

机构地区：[1]南京江北新区中心区发展有限公司,南京211899 [2]南京工业大学交通运输工程学院,南京210009

出　　处：《工程建设与设计》2021年第13期190-192,共3页Construction & Design for Engineering

摘　　要：超轻陶粒土作为土工回填材料具有质量轻、强度高、透水性好、施工简便等优点。为更好理解其物理力学特性,采用电镜扫描获取了陶粒内气孔尺寸分布特征,进行了净陶粒土和水泥胶结陶粒土的一维压缩试验及单颗粒压碎试验,并从微观上进行了机理分析。结果表明,陶粒是一种"外强内弱"的壳-核复合颗粒,水泥胶结能显著提高单颗粒的抗压强度并因此可降低陶粒土的压缩性。Ultra-light-weight expansive clay aggregates(ULECA)can be used as geotechnical backfill due to its advantages in light weight,high strength,high permeability and easy workability.To understand the physical and mechanical behavior of ULECA soils,SEM image analyses on the size distribution of internal pores,odeometer tests on clean and cemented ULECA soils,and single particle compression tests were performed.The effects of cementation on single particle crushing strength and deformation behavior of ULECA soils and the related microscopic mechanisms were analyzed.The results show that ULECA is a kind of compound particle with a stronger coating layer and a weaker inner core.The extent of particle breakage in clean ULECA soil increases with load and decreases as the void ratio reduces.The addition of cementation can significantly increase the single particle crushing strength and as a result lower the compressibility of ULECA soil.

关 键 词：陶粒土 多孔轻质材料 水泥胶结 一维压缩 

分 类 号：TQ174.41[化学工程—陶瓷工业] TU45[化学工程—硅酸盐工业]