Effect of high temperature heat treatment on mechanical and thermal conductivity of foam concrete
Three kinds of foam concrete with different water binder ratio were prepared by physical foaming with Portland cement as raw material.The effects of high temperature heat treatment on the phase structure,micro morphology,compressive strength residual rate,mass loss rate,water absorption rate and thermal conductivity of foam concrete were studied.The results showed that when the heating temperature was lower than 500 ℃,the concrete surface cracks were less,the compressive strength residual rate and mass loss rate of foam concrete with water binder ratio of 0.5 decreased most,and the mass loss rate of foam concrete with water binder ratio of 0.4 decreased least.When the heating temperature reached 900 ℃,there were many cracks on the concrete sur-face and obvious through cracks appearing.The compressive strength residual rate of foam concrete with three water binder ratios tended to be the same,all of which were below 20％.The mass loss rate of foam concrete with water binder ratio of 0.4 was the lowest 20.18％,and the water absorption rate of foam concrete with wa-ter binder ratio of 0.5 was the highest 69.2％.The thermal conductivity test showed that at the same tempera-ture,the thermal conductivity of foam concrete with water binder ratio of 0.4 was the lowest.When the heating temperature reached 900 ℃,the thermal conductivity of foam concrete with water binder ratio of 0.4 was at least 0.2975 W/(m·K),which had excellent performance in fire prevention and thermal insulation applica-tions.
foam concretehigh temperature heat treatmentwater binder ratiomechanical propertiesthermal conductivity
万方数据
维普
