偏高岭土改善灰土强度的试验研究  

Study on thestrength of lime-soil improved by metakaolin

作　　者：刘春龙[1] 刘乃飞 刘奉银[1] 杨珺珑 LIU Chunlong;LIU Naifei;LIU Fengyin;YANG Junlong(Institute of Geotechnical Engineering, Xi'an University of Technology, Xi'an 710048, China;School of Civil Engineering, Xi'an Univ. of Arch.&Tech., Xi'an 710055, China;Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering, Xi'an Univ. of Arch.&Tech., Xi'an 710055, China)

机构地区：[1]西安理工大学岩土工程研究所,陕西西安710048 [2]西安建筑科技大学土木工程学院,陕西西安710055 [3]西安建筑科技大学陕西省岩土与地下空间工程重点实验室,陕西西安710055

出　　处：《西安建筑科技大学学报（自然科学版）》2019年第2期206-211,共6页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：国家自然科学基金(41372304;10872162);西安建筑科技大学人才科技基金项目(RC1804);西安建筑科技大学自然科学专项(ZR18017)

摘　　要：灰土被广泛用作建筑物和构筑物的基础,本文通过添加偏高岭土来进一步改善其力学性能,以期为改性灰土的应用提供试验依据.灰土强度受其组成原料如石灰含量、含水率和粘土性质的影响较大,通过控制石灰和偏高岭土含量以及水固比等因素,研究偏高岭土的加入对常规灰土材料抗压强度和软化系数的影响,并通过对含水率变化分析和扫描电镜揭示其内在机理.根据试验结果的对比分析,发现偏高岭土不仅能改善灰土材料的强度,明显缩短其强度形成时间,而且明显的提高灰土试样的软化系数.无论添加偏高岭土与否,试样抗压强度随水固比、石灰含量和偏高岭土含量均存在一个最佳配比.偏高岭土与Ca(OH)_2和水发生化学反应,反应产物致使灰土试样的结构更加致密,从而改善了试样的力学性能.The lime-soil is widely used as the foundation of buildings and structures. In this paper, the addition of metakaolin is used to further improve its mechanical properties, to provide experimental basis for the application of modified lime soil. The strength of lime soil is greatly affected by its constituent materials such as lime content, water content and clay properties. The effects of the addition of metakaolin on the compressive strength and softening coefficient of lime soil materials are studied by controlling the contents of lime and metakaolin and water-solid ratio. The intrinsic mechanism is revealed by analyzing the moisture content and scanning electron microscopy (SEM) photos. Regardless of the addition of metakaolin, the compressive strength of the sample has an optimal ratio with water-solid ratio, lime content and metakaolin contents. The reaction products of metakaolin and lime makes the structure of the lime soil sample more compact, in improving the mechanical properties of the sample.

关 键 词：偏高岭土 灰土 火山灰反应 抗压强度 细观结构 

分 类 号：TU444[建筑科学—岩土工程]