摘要
为评价SH固土剂的固化作用及对盐渍土的固化效果,分别完成了固化前后蒙脱石、高岭石、石英砂、盐渍土的X射线衍射与红外光谱测试、4种固化土的实体显微镜和偏光显微镜观察、固化前后盐渍土的扫描电镜微观观察,以及固化盐渍土的力学性能测试与冻融实验。实验结果表明:4种固化土的X射线衍射谱图和红外光谱图与固化前的吻合;各固化土的矿物成分没有发生改变,SH固土剂的官能团与黏土矿物均未发生化学键的结合,没有生成新相物质;SH固土剂干燥后形成弹性立体丝网,将土颗粒黏结在一起,提高了固化土的强度;固土剂填塞部分孔隙,减小了土的孔隙度;SH固土剂包裹土颗粒,增强了土的憎水性。固化盐渍土的力学性能测试和冻融实验结果证实,掺加SH固土剂提高了土的强度与抗变形性能、水稳性、抗渗性和抗冻融性能。SH固土剂与黏土矿物及盐渍土未发生化学反应,固化土力学性能的提高为固土剂的物理作用所致。
This paper studies the solidification mechanism and identificates the chemical reaction between SH agent and clay minerals.It carries out the X-ray diffraction test,infrared spectrum test,microscope and polarizing microscope observation,and scanning electron microscopy detection,respectively,on clay minerals(montmorillonite,kaolinite),quartz,saline soil and theirs solidifying one with SH agent.At the same time,in order to evaluate the effect of solidification,it carries out the mechanical tests and freeze-thaw test on solidified lime-saline soils and SH agent-lime￣saline soils.The results show that XRD spectrum and IR spectrum of the solidified materials are generally consistent with one of original materials,and the mineral composition is not changed.The functional groups of SH agent are not combined with the clay minerals,and no new substance is generated.SH agent produces an elastic and three-dimensional network and the silk fills the pores,and the soil particles are bonded in a whole,which increases the strength and decreases pore ratio of solidifying saline soil.Meanwhile,because of SH agent wrapping soil particles,the adhesive force and hydrophobicity of soil particle are increased.The results of the mechanical tests on SH agent-lime￣saline soil have proved that SH agent can improve the strength in air and water,deformation resistance,anti-permeability of saline soil.The results of freeze-thaw experiments confirm that the three-dimensional network and the silk can partly resist the expansion and contraction of soil during freezing and thawing,and weaken the structural damage of soil.Therefore,the addition of SH agent is helpful to enhance the freeze-thaw resistance of solidified soil.SH agent does not generate chemical reaction with clay minerals.The improvement on the mechanical properties of saline soil mainly depends on the physical effect between SH agent and soil particles.
作者
魏丽
柴寿喜
WEI Li;CHAI Shouxi(Tianjin Chengjian University,Tianjin 300384)
出处
《工程地质学报》
CSCD
北大核心
2018年第2期407-415,共9页
Journal of Engineering Geology
基金
天津市自然科学基金项目(17JCYBJC22200
17JCZDJC39200)
天津市科技支撑计划重大项目(15ZXCXSF00070)
天津市高等学校科技发展基金计划项目(20120911)资助
关键词
固化作用
微结构
固化土强度
滨海盐渍土
SH固土剂
Solidification mechanism
Micro structure
Strength of solidified soil
Inshore saline soil
SH agent
作者简介
第一作者:魏丽(1979-),女,硕士,副教授,从事滨海盐渍土的改性固化与加筋研究.Email:weili_79@126.com
