摘要
【目的】混凝土材料的多孔亲水特性易受水和腐蚀介质的影响,严重降低材料的耐久性。聚焦于混凝土疏水性相关的物化性能,采用了一种新型的甲基硅氧烷基疏水粉对混凝土进行改性,旨在增强混凝土的耐久性能。【方法】对不同水灰比下的甲基硅氧烷基疏水混凝土样品进行力学性能、疏水性能、水化反应、热重、晶体结构和基团特性分析,研究这种疏水粉对混凝土物化性能的影响。【结果】疏水粉的掺入可使混凝土的疏水性能显著提高,0.2、0.3和0.4水灰比试样的最大疏水角分别达到156.5°、152.6°和152.9°,表现出超疏水性能;疏水粉的掺入使得砂浆试样的吸水率降低,0.2、0.3和0.4水灰比试样的吸水率最低值分别达到0.84%、0.86%和2.89%;具有疏水性能的0.2、0.3和0.4水灰比试样的抗压强度降低率为7.3%~22.7%;疏水粉会抑制水泥早期水化,促进最终水化程度的增加;疏水粉的掺入对晶体结构的影响不大,能够使混凝土的疏水基团增多。【结论】甲基硅氧烷基疏水粉的掺入明显增强了混凝土的疏水性能,提高了混凝土的水化程度,降低了疏水外加剂对混凝土的不利影响,提升了混凝土的耐久性。
【Objective】The porous hydrophilic characteristics of concrete materials are susceptible to the effects of water and corrosive media,which severely reduce the durability of the material.Focusing on the physicochemical properties related to the hydrophobicity of concrete,this study investigates the use of a novel methylsiloxane-based hydrophobic powder to modify concrete with the aim of enhancing its durability.【Methods】By analyzing the mechanical properties,hydrophobicity,hydra-tion reactions,thermogravimetric behavior,crystal structure,and functional group characteristics of methylsiloxane-based hy-drophobic concrete samples with different water-to-cement ratios,the effects of this hydrophobic powder on the physicochemi-cal properties of concrete were studied.【Results】The incorporation of hydrophobic powder significantly enhanced the hydro-phobicity of concrete,with the maximum water contact angles of 156.5°,152.6°,and 152.9°observed for samples with wa-ter-cement ratios of 0.2,0.3,and 0.4,respectively,demonstrating superhydrophobicity.The addition of the hydrophobic powder reduced the water absorption of the mortar samples,with the lowest water absorption of 0.84%,0.86%,and 2.89%for the 0.2,0.3,and 0.4 water-cement ratio samples,respectively.The compressive strength of the hydrophobic concrete samples decreased by 7.3%to 22.7%.The hydrophobic powder inhibited the early hydration of cement but promoted in-creased hydration at later stages.The addition of the hydrophobic powder had minimal impact on the crystal structure of the concrete,but it increased the quantity of hydrophobic groups in the material.【Conclusion】The incorporation of methylsilox-ane-based hydrophobic powder significantly enhances the hydrophobicity of concrete,increases its hydration degree,mitigates the adverse effects of hydrophobic additives on concrete,and ultimately improves the durability of the material.
作者
吕亚军
张康捷
乔敏
项腾飞
党钧陶
董树林
侯泳辉
宋彩红
马肖峰
LYU Yajun;ZHANG Kangjie;QIAO Min;XIANG Tengfei;DANG Juntao;DONG Shulin;HOU Yonghui;SONG Caihong;MA Xiaofeng(North China University of Water Resources and Electric Power,Zhengzhou 450046,China;State Key Laboratory of High Performance Civil Engineering Materials,Jiangsu Sobute New Materials Co.,Ltd.,Nanjing 211103,China;Anhui University of Technology,Ma′anshan 243002,China;China MCC22 Group,Tangshan 063000,China;Henan Textile and Architectural Design Institute Co.,Ltd.,Zhengzhou 450007,China)
出处
《华北水利水电大学学报(自然科学版)》
北大核心
2025年第5期132-141,共10页
Journal of North China University of Water Resources and Electric Power:Natural Science Edition
基金
国家自然科学基金项目(51979169,52201056)。
关键词
甲基硅氧烷基疏水粉
疏水混凝土
疏水性能
物化性能
methylsiloxane-based hydrophobic powder
hydrophobic concrete
hydrophobic property
physicochemical properties
