纳米SiO2改性陶粒混凝土冻融损伤规律及模型研究

为研究纳米SiO2改性陶粒混凝土在不同溶液冻融环境下的抗冻性能,设计了四种溶液(水、硫酸盐、碳酸盐、复合盐)冻融环境,采用快速冻融法,以质量损失率及相对动弹性模量为指标对其冻融损伤规律进行了研究,并基于试验数据建立了抗冻性能退化模型。结果表明:在盐溶液冻融环境下,陶粒混凝土质量损失及相对动弹性模量高于水冻环境;当盐溶液浓度相同时,硫酸盐溶液冻融环境对混凝土的质量及动弹性模量的损伤较碳酸盐溶液强,复合盐类溶液冻融损伤居中;基于试验数据建立的抗冻性能模型可较好地反映纳米SiO2改性陶粒混凝土在不同冻融溶液环境下的冻融损伤规律。

Research on Freeze-thaw Damage Law and Model of Nano-SiO2 Modified Ceramsite Concrete

In order to study the antifreeze performance of nano-SiO2 modified ceramsite concrete in different freeze-thaw solution environments,four freeze-thaw environments(water,sulfate,carbonate,compound salt)were designed.The rapid freeze-thaw method was used to study the freeze-thaw damage law using the mass loss rate and the relative dynamic elastic modulus as the measurement indicators.And based on the test data,a degradation model of frost resistance performance was established.The results show that the mass loss and relative dynamic modulus of elasticity of ceramsite concrete are higher in the freezing and thawing environment of salt solution than in the water and freezing environment.When the salt concentration is the same,the damage of the freeze-thaw environment of the sulfate solution to the concrete quality and dynamic elastic modulus is stronger than that of the carbonate,and the freeze-thaw damage ability of the compound salt solution is in the middle.The frost resistance model established based on the experimental data can better reflect the freeze-thaw damage law of nano-SiO2 modified ceramsite concrete in different freeze-thaw solution environments.