盐冻环境下混凝土抗盐冻性能研究OA

Under the erosion and freezing of rain and snow,the hydraulic structures in northern China often suffer from salt freeze failure,which has a serious impact on the impermeability,durability and long-term stable operation of hydraulic structures.In order to reduce the degree of salt freeze damage,the effects of slag powder,silica fume and fly ash on the salt freeze resistance of hydraulic concrete were experimentally explored,and the mechanism of bubble characteristics against salt freeze was analyzed by SEM scanning electron microscope.The results show that the introduction of independent and evenly distributed airtight bubbles in hydraulic concrete can significantly enhance its salt freeze resistance,and the salt freeze resistance when the water glue is relatively large is mainly affected by the bubble structure,and the addition of air entraining agent to generate a good bubble structure can effectively improve the salt freeze resistance.When the water-glue ratio<0.32,the influence of bubble structure characteristics decreases,and under this condition,no air-entraining agent can maintain a high level of salt freeze resistance.