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Photogrammetry is a method developed in the early XIXth century. Nowadays, with digital photography associated to the development of image processing and its automation, this technique has become appealing in different fields of application. In this paper, the authors analysed the current feasibility and advantages of using photogrammetry in structural monitoring. First, the method was calibrated using two laboratorial tests: (1) monitoring of failure and creep tests of long-span reinforced concrete beams; and (2) monitoring of steel beam-to-column connections. Then, the method was tested on site, namely, in monitoring the deformations of a footbridge subjected to different loading situations. It was concluded that photogrammetry can be used in structural monitoring with accuracy and exhibiting additional advantages in relation to traditional methods, namely: (1) an almost unlimited number of measuring points can be considered and automatically processed; and (2) hardware is unnecessary and, therefore, it can be used under almost any situation where traditional methods cannot be employed. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]