粉煤灰混凝土高温后力学性能与龄期的关系

RELATIONSHIP BETWEEN MECHANICAL PROPERTY AND CRUING AGE OF FLY ASH CONCRETE AFTER HIGH TEMPERATURE

粉煤灰混凝土硬化过程中,由于粉煤灰的水化速度慢导致混凝土的早期强度偏低,但能显著提高混凝土后期强度(28 d以后),并且可改善混凝土的耐热性。以三种养护龄期28,56,90 d的粉煤灰混凝土试块为研究对象,高温作用后自然冷却,分析养护龄期对残余立方体抗压强度、残余劈拉强度、超声声速值、回弹值的影响。

During fly ash concrete hardening process,the slow hydration of fly ash leads to low early strength of concrete,but can significantly improve the late strength of concrete（28d later）,and also improve the heat resistance of concrete.In this paper,three kinds of curing ages including 28,56,90 d of the fly ash concrete specimens were used for the study,which naturally cooled after high temperature,it was analyzed the effect of curing age on the residual compressive strength,the residual splitting tensile strength,ultrasonic sound velocity and rebound value.