土工基础

›› 2014, Vol. 28 ›› Issue (4): 138-141.

• 工程实录 • 上一篇    下一篇

南阳中膨胀土水泥改性的室内试验研究

岑 胜1，王协群2，焦秋霞3，范华伟4   

  1. （1.厦门翔业集团有限公司,福建厦门  361006；2.武汉理工大学 土木工程与建筑学院，武汉  430070；
    3.洛阳水利勘测设计院有限责任公司，河南洛阳  471000;4.中国医药集团联合工程有限公司,武汉  430000）
  • 收稿日期:2013-07-31 出版日期:2014-08-20 发布日期:2014-08-27
  • 作者简介:岑胜（1986-），男，硕士，研究方向为岩土工程。
  • 基金资助:

    基金项目：膨胀土判别指标及分类体系探究（125206009），武汉理工大学自主创新研究基金，批准号：2012ZY050

Laboratory Experimental Testing of Cement Modified NanyangMedium Expansive Soils

CEN Sheng1, WANG Xiequn2, JIAO Qiuxia3, FAN Huawei4   

  1. （1.Xiamen Iport Group Co. Ltd, Xiamen 361006;2.College of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070;
    3.Luoyang Hydrological Investigation and Design Co., Ltd., Luoyang 471000; 4.Sino Pharmengin Corporation, Wuhan, 430000)
  • Received:2013-07-31 Online:2014-08-20 Published:2014-08-27

摘要： 取南水北调中线工程南阳段自由膨胀率77%的中膨胀土，开展了一系列不同水泥掺灰率和不同龄期下，压实度为98%试样的物理力学特性试验。通过对素膨胀土与改性膨胀土的胀缩性、界限含水率、级配及无侧限抗压强度的对比，揭示了掺灰率及养护龄期对膨胀土改性效果的影响。试验结果表明：（1）随掺灰率的增加，改性膨胀土的胀缩性指标及反映黏土亲水性的液限和塑性指数均降低、胶粒含量减小、级配曲线随趋于平缓、无侧限抗压强度和弹性模量增加；合理的掺灰率应取6%；（2）随养护龄期的增加，胀缩性指标、液限、塑性指数、胶粒含量减小，无侧限抗压强度和弹性模量则增大。

关键词: 膨胀土, 水泥改性, 室内试验

Abstract: A cement modified Nanyang medium expansive soil with a free expansion ratio of 77% is extensively studied in the laboratory conditions under a degree of compaction of 98%. The expansive properties of modified and unmodified expansive soil samples, such as, free expansion ratio, shrinkswelling indices, Atterberg Limits, grain size distribution and unconfined compressive strength, are tested with different cement ratios and curing ages. The following conclusions can be drawn: 1) with the increase of cement content, the liquid limit and plastic index, which are the indices of shrinkageswell and plasticity of modified expansive soils, are reduced. The clay content in soil samples is also reduced. A flat gradation curve is observed. The unconfined compressive strength and elastic modulus are increased. The optimum cement ratio is tested to be 6%. 2) with the increase of curing time, the shrinkageswelling indices, liquid limit, plasticity index and clay content are reduced and the unconfined compressive strength as well as elastic modulus are increased.

Key words: Expansive Soils, Cement Modification, Laboratory Testing