Characterisation of concrete cracking during laboratorial tests using image processing

The evolution of the crack pattern during laboratorial tests is quite important to adequately characterise the specimen’s response. Usually this is done by hand drawings. Hence, the development of an automatic tool capable of detecting, mapping and measuring crack patterns would be of upmost importance.The recent developments of digital optical equipment and methods widened their original field of application. Nowadays, laboratorial test monitoring is surely one of these potentially interesting new areas. In this paper, an innovative method named ‘MCRACK’ is introduced, aiming to automatically characterise cracking using digital image processing. First, ‘MCRACK’ is tested on a crack width ruler. Afterwards, the method is applied to push-off specimens tested until failure to study its advantages compared to traditional methods.It is concluded that ‘MCRACK’ gives a considerable increase of data, with higher reliability, automatically processed and at a significantly reduced working time.

► The method MCRACK uses image processing to map and measure cracking. ► A global–local approach allows studying an entire surface along the test. ► Apply a technique of low computational-cost. ► Uses non-professional cameras. ► Is a non-contact robust and cost-effective measurement method.