The investigation of aggregate grain size effect on fracture toughness of ordinary concrete structures

✍ Scribed by Andrzej Bochenek; Grzegorz Prokopski

• Publisher: Springer Netherlands
• Year: 1989
• Tongue: English
• Weight: 441 KB
• Volume: 41
• Category: Article
• ISSN: 1573-2673
• DOI: 10.1007/bf00018657

✦ Synopsis

The material under investigation was ordinary concrete of B 20 class, different in the sizes of coarse aggregate and water-cement ratio of the same value w/c = 0.55. It was found during the tests that there were two kinds of sample cracking mechanisms. Some samples cracked at the moment of the initiation of slit (when Po = Pmax); in others the decohesion force Pma~ exceeded PQ, which was identified as a minor deflection or relative extremum of the curve. The frequency of the second type of cracking increased with the growing size of coarse aggregate grains. Together with the growth of the grain size, the angle of curve inclination also became smaller. This phenomenon can be explained by the fact that, in the process of decohesion, the aggregate grains are relocated and the system of contact between them changes, so the K~, depends on coarse aggregate.