用废玻璃改善混凝土高温性能的研究

Concrete was made with 0.155.00 mm waste glass replacement of natural sand and limestone crushed stone at levels of 10%, 30%, 60% and 100% (by mass). Concrete specimens were tested for their mass loss rate, compressive strength and splitting tension strength at 300, 400, 600, 900°C. The experimental results obtained show that mass loss rate increase with increase of temperature(t). Concrete internal defects and degradation are developed with temperature increases, leading to concrete strength decrease. It is found that the replacement of concrete aggregate with waste glass hindered concrete degradation from high temperature effect, the enhancement effect of waste glass at high temperature increases with its replacement level, the optimal beneficial effect on concrete strength is achieved for concretes with 80%-100% waste glass replacement at temperature 800-900°C. The enhancement effect can be described and analyzed using keeping rate (P) of strength, gradient of regression equation for keeping rate (Pc) of compressive strength-time(t) and high temperature enhancement coefficient (δ) of waste glass, and δ tends to be the best parameter.