Laboratory experience of flood effects monitoring in fired-clay bricks and adobe

Due to climatic change, extreme natural events such as storms, heavy rains, floods, landslides become more and more frequent and prolonged. This constitutes a hazard for economic activities, people, structures and infrastructures. With regard to constructions, these undergo rapid changes of their termo-hygrometric conditions due for example to wind-driven rain or flooding. Although the dramatic effects of these extreme events on constructions and buildings become very evident, very little has been studied so far about the behaviour of construction materials when undergoing sudden and abundant changes of physical parameters, for example moisture content and propagation. These changes may have direct consequences on the mechanical characteristics of the construction materials. With attention to historical constructions, an experiment was carried out in the laboratory, considering construction materials in particular masonry units new or sampled from historical structures. These units, including fired-clay bricks and adobe were subject to capillary moisture rise in order to study their swelling behaviour at increasing moisture content, but also the speed of capillary rise and the capillary suction rate. The monitoring of the experiment has taken place by means of IR thermography camera and high definition optical monitoring through digital image correlation. Initial results obtained, together with porosity characteristic, visual observations and mechanical tests carried out on the materials, showed unexpected differences of behaviour between the chosen specimens. The values obtained will be critically discussed in view of risk protection and mitigation measures from flooding in historical constructions.