硫酸盐干湿循环作用下烧结粘土砖劣化机理及强度预测

Study on the Deterioration Mechanism and Strength Prediction of Clay Bricks under Cyclical Wetting and Drying in Sulfate Solution

通过实验研究了粘土砖在浓度为10%硫酸盐干湿循环作用下质量、相对动弹性模量及强度退化机理,结果表明,粘土砖质量和相对动弹性模量随干湿循环次数的增加均表现出先略有增长,循环约30次后下降的规律,强度也是先增长而在循环约40次左右开始下降.采用灰色理论建立了硫酸盐环境下粘土砖强度退化预测函数,并与实验结果进行了对比,结果表明,模型预测值与实验值,除了个别点误差较大外,其余点上的误差均在5%以内,说明强度退化函数预测的合理性,并预测粘土砖使用寿命.

The degradation mechanism of mass,relative dynamic modulus of elasticity and strength of clay bricks under cyclical wetting and drying of 10%sulfate was studied experimentally.The results show that the mass and relative dynamic modulus of elasticity of clay bricks increase slightly with the increase of wet dry cycles,and then decrease after about 30 cycles,while the strength of clay bricks increases first and then starts to decrease after about 40 cycles.The grey theory was used to establish the prediction function of strength degradation of clay bricks in sulfate environment.Results show that the differences between the predicted value of the model and the experimental value are all less than 5%except for some larger differences at a few individual points,which proves the rationality of the prediction function of strength degradation in predicting the service life of clay bricks.