膨润土对混凝土抗渗透性能影响的研究

为研究膨润土对混凝土抗渗透性能的影响,测试了不同试验条件下混凝土气体渗透系数和电通量,分析了混凝土抗气体渗透性能和抗氯离子渗透性能的相关性,并利用扫描电子显微镜观察了内掺膨润土混凝土的微观结构。研究表明:膨润土掺量在0~8%范围内,混凝土的气体渗透系数与电通量均先降低后升高,当膨润土掺量为4%时,混凝土气体渗透系数和电通量最低;适当降低水胶比可以有效改善混凝土抗气体渗透和抗氯离子渗透性能;混凝土气体渗透系数与电通量显著正相关;微观分析表明:掺膨润土混凝土的抗渗透性能可能与水化硅酸钙凝胶体系内孔隙的填充和C-S-H之间的连接程度有关。

Effect of bentonite on the permeability resistance of concrete

In order to study the effect of bentonite on the permeability resistance of concrete,the gas permeability coefficient and electric flux of concrete under different test conditions were tested,the correlation between gas permeability resistance and chloride ion penetration resistance of concrete was analyzed and observed by scanning electron microscope,the microstructure of the concrete mixed with bentonite.The research shows that the content of bentonite is in the range of 0~8%,and the gas permeability coefficient and electric flux of concrete are first decreased and then increased,when the amount of bentonite is 4%,the concrete gas permeability coefficient and electric flux are the lowest.Properly reducing the water-to-binder ratio can effectively improve the resistance of concrete to gas permeation and chloride ion penetration.Correlation analysis found that the concrete gas permeability coefficient is significantly positively correlated with the electric flux.Microscopic analysis shows that the permeability resistance of bentonite-incorporated concrete may be related to the degree of pore filling and C-S-H connection in the hydrated calcium silicate gel system.