再生混凝土抗压强度尺寸效应试验研究

Experimental study on size effect of compressive strength of recycled concrete

以废弃混凝土块经过分离、破碎、清洗分级后充当再生骨料,制作12个边长分别为70、100、150、200 mm的再生混凝土立方体试块。研究了同一取代率、同一配合比、同一强度等级下,不同尺寸再生混凝土抗压强度实测值与试块尺寸之间的关系。试验结果表明,再生混凝土立方体抗压强度存在明显的尺寸效应,随着再生混凝土试块尺寸的逐渐增加,再生混凝土立方体抗压强度值逐渐减小,但减小的幅度逐渐变缓。

Twelve sets of recycled concrete cubes with 70,100,150 and 200 mm lengths were arranged with waste concrete as recycled aggregate.These cubic specimens are constructed by the same substitution rate,the same mixing ratio and the same strength grade.The relationship between the measured compressive strength and the size of specimen is obtained by experiment.The test results show that the compressive strength of recycled concrete decreases with the increase of specimen size.Furthermore, the magnitude of the decrease on the compressive strength is gradually slowing down as the size of the specimen increases.