* ICITE-CNR (Central Institute for Building Industrialization and Technology)
** UNICALCE (Lime and mortar producer)

The objective was the verification of the physical and mechanical behaviour of cement mortars with the addition of hydrated lime in order to identify those able to improve the performance of masonry. Tests were made on 14 types of mortar and solid masonry specimens to establish the bulk densities of cement times and sands and the grading curve of the sand; the compressive strength, capillary water absorption and soaking, of bricks; bending and compressive strength, capillary water absorption, soaking and modulus of elasticity of smaller mortar samples; and compressive and shear strength, mortar/brick adherence, watertightness, modulus of elasticity of solid masonry samples. The results clearly show that even with very small amounts of hydrated lime in mortars it is immediately possible to obtain better workability, an increased adherence between mortar and brick, mechanical strengths that are equal to or greater than the ones which could be obtained with cement mortars, as well as an increase of watertightness.