Evaluation of damage evolution in masonry due to environmental parameters and salt capillary rise

Masonry constructions, historically used all over the world, largely show the effects of environmental decay in their structure and materials. Accurate studies on the causes of damage and on the consequences on physical, chemical and mechanical properties of masonry are still required. In the frame of the 7FP EU project SMooHS, a laboratory research is conducted aimed at provoking the damage, evaluating its evolution in brick walls and at establishing a correlation between environmental decay and loss of load-bearing capacity of masonry. Thus, two large specimens made of bricks and lime mortar have been built and placed outside the lab to address environmental degradation, in addition to brine capillary suction, using different salt solutions (sodium chloride and sodium sulphate). The decay effects on the two walls have been compared. The monitored climatic parameters (air T, RH, rainfall) have been used for determining the number of possible salt crystallization/hydration cycles occurred and, thus, to estimate the inner decay of the structure. In parallel, the masonry component materials have been physically and chemically characterized. Sonic tests in superficial transmission mode have been repeated after 2 seasons of aging, in order to estimate the decay history on the masonry materials.