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DRMS and penetrometric tests were applied directly on site on bedding mortars of bricks in San Francesco Church, in Pisa (Tuscany, Italy ) and on drilling core samples of nucleus of walls (Fig. 1) coming from San Francesco Church (Pisa), Giotto’s Bell Tower and Palazzo Vecchio (Florence, Italy).

San Francesco Church (Pisa, Italy), built between XIII and XV century, is a very important catholic church in Italy, now undergoing to an extensive restoration plan.

Figure 1: Examples of drilling core samples subjected to drilling (left side) and penetrometer (right side) tests.

During the most recent diagnostic campaign promoted by Opera del Duomo of Florence and conducted on the Giotto’s Bell Tower to investigate the history, the structures and the materials of external façades and masonry, some samples of mortars were obtained. The mortar samples were taken from the foundations and from the masonry of the II and V levels of the bell tower, using a core drill.

Core samples of foundation structures from Palazzo Vecchio (headquarters of municipality of Florence town) were also tested.

Tested mortars were prepared before the measurements: for San Francesco Church on site case study, the plaster of the wall was removed, in order to have bedding mortars of bricks exposed; the core samples were cleaned from coring residues.

The chemical, mineralogical and petrographic studies carried out on these mortar samples allowed us to classify these mortars as aerial lime mortars or weakly hydraulic mortars. They have a fine grained aggregate (mean grain size ranges from 500 to 200 mm, maximum grain size from 1 mm to 1.2 mm) with a prevalently silicatic composition and a binder/aggregate ratio from 1/1 to 1/3.