PSI - Issue 11

Sonia Boschi et al. / Procedia Structural Integrity 11 (2018) 169–176 Author name / Structural Integrity Procedia 00 (2018) 000–000

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evolutions and transformations over the centuries, the geometrical survey and focusing on the structural aspects: the typologies of floors, roofs and masonry walls are investigated through both visual inspections and non-destructive (NDT) in-situ tests. Subsequently, and thanks to this full knowledge acquired, the structure is disaggregated into identified structural units, that may be considered having a unitary response against seismic actions. Each of them is seismically analysed, thus identifying properties, peculiarities and deficiencies and designing preliminary retrofit interventions.

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Fig. 1. (a) Civitali Institut aerial image; (b) internal cloister; (c) Civitali main front street on the East side.

2.2. Structural description and in situ investigation

The extensive investigation campaign adopted to fully know the structure included:

• n.47 essays on vertical masonry structure through the removal of plaster portions (about 1×1 m) in order to identify the types and quality of masonry types, those of the constituents and the structural details; • n.14 essays on horizontal elements (n.9 horizontal slabs and n.5 vaulted structures) aimed at identifying types, thicknesses and structural slab packages; • thermographic investigations by means of a thermal imaging camera, to identify the wall texture or the type of horizontal elements (where essays could not be done); • experimental tests on the walls aimed at directly defining their mechanical characteristics; in particular: ‒ n.7 tests with single and double flat-jacks, to estimate the in situ stress state and the modulus of normal elasticity of the masonry (E); ‒ n.8 tests with penetrometric instrumented drill for the evaluation of the mortar compressive strength; ‒ n.7 endoscopies to verify the consistency of the wall thickness; • n.7 static and dynamic tests on tie-rods of the major vaults covering the ground floor to estimate the stress state.