考虑龄期影响的福州地区超声回弹综合测强曲线

依据福州地区常用配合比,采用当地常用原材料,制作强度等级从C20~C45的200余个混凝土试块.利用超声回弹法进行测量,在不同龄期下,对不同强度的混凝土试块在与实测强度进行比较后,提出考虑龄期影响的修正后的地区超声测强曲线.结果表明:提出的福州地区综合测强曲线的预测精度有明显提高,综合误差小于15%,可以满足规范对地区测强曲线的要求.

Prediction Curves of Concrete Strength Considering Influence of Different Concrete Ages Using Ultrasonic-Rebound Combined Method

More than 200 standard concrete samples with strength from C20 to C45 are casted using local material in Fuzhou with common mix proportion. Ultrasonic-rebound combined method is utilized to test different age concrete samples. An improved prediction curves considering the influence of ages is proposed by comparing the prediction results with the experimental results. Compared to the prediction curve suggested in the current code, the proposed curve greatly improves the prediction precision. The result shows that the comprehensive error is less than 15%, which can meet the requirement of the current code.