高温作用后粉煤灰混凝土的无损检测

Nondestructive Examination of Fly Ash Concrete After High Temperature

[摘要]以养护龄期28d不同掺量粉煤灰混凝土试块为研究对象，250～650℃高温作用后经自然冷却和喷淋冷却两种方式，对其进行超声及回弹试验，利用Excel的一元线性回归、二元线性回归、二元非线性回归，分析了回弹、超声一回弹检测高温作用后粉煤灰混凝土残余抗压强度方法的适用性，并且建立高温后粉煤灰混凝土强度与回弹值、声速值之间的回归方程。

Taking concrete specimens with different amount of fly ash after 28d maintenance for the study, the specimens are heated in 250 - 650℃ high temperature then cooled in two ways of natural cooling and spray cooling. Authors have the tests with ultrasonic method and rebound method, then using a linear regression, binary linear regression, binary non-linear regression of Excel to analyze the applicability of residual strength of fly ash concrete at high temperature with the rebound method and ultrasonic method. The regression equations of rebound values, sound values and fly ash concrete strength after high temperature are established.