PSI - Issue 11

Massimiliano Lucchesi et al. / Procedia Structural Integrity 11 (2018) 177–184 M. Lucchesi, B. Pintucchi, N. Zani/ Structural Integrity Procedia 00 (2018) 000–000

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were unfortunately performed for the most part unmindful of the building’s architectural and structural aspects. An in-depth study of this structural system is particularly warranted for several reasons. Firstly, the size of the overall structure is substantial, in particular the height of the pillars sustaining the upper system of vaults is considerable. Moreover, the aforementioned previous, misguided attempts at structural consolidation have seriously altered the structure. These works, consisting of steel-profile beams and columns, will likely need to be removed in view of the plan to restore and reuse the building complex. Another important issue is the fact that the vaults underlie a roadway and are therefore subject to significant vibrations from traffic loads. In light of the foregoing, some numerical investigations have been performed to check the static state and stability of the Palazzo Monte di Pietà cellars (in accordance with current Italian building codes). For this purpose, the finite element code MADY, developed by the authors for the static and dynamic analyses of masonry constructions, has been used (Lucchesi et al., 2017a). The code provides fairly general constitutive equations for dealing with different types of masonry, taking into account both its low tensile strength and its limited ability to withstand compressive and tangential stresses (Lucchesi et al., 2017b, 2018). Moreover, in the case of particularly slender masonry beams, the code can also consider the effects of geometric non-linearities (Pintucchi and Zani, 2009). In the following, after a description of the building and its historical importance, the main results of the nonlinear analyses performed under vertical loads are presented. As a preliminary study, these analyses have been conducted with reference to a sub-system consisting of a four-bay two-level vaulted structure. Originally, Livorno was a small, poor town south of the Sinus Pisanus , the extra-urban port of Pisa. During the sixteenth century, the Grand Duke of Tuscany was in dire need of a port, as the Sinus was being filled with alluvial deposits, making it unnavigable: the Medici had to construct another new port 1 . To create a large enough port, a new city firstly had to be founded and the citizens engaged. Hence, some laws were promulgated to favor the settling of merchants of whatever nation, by granting them certain privileges as an incentive. From the second half of the sixteenth century, the expansion of the city required redesigning the defensive walls and fortresses. The New Fortress (so-called to distinguish it from the previous one known today as the Old Fortress built between 1518 and 1532 by Antonio Sangallo il Vecchio) was built as part of the city-fortress project commissioned in 1576 by the Grand Duke Francesco I to Buontalenti. The New Fortress, originally much larger than the current one, was joined to the Old Fortress by a defensive wall. Over time, however, the system of fortifications and canals lost its military-defensive function as the city’s port commercial activities grew in importance. The city expanded further west both by reclaiming land from the sea and by reducing the size of the New Fortress. Crossed by three canals, a new district was built with stilt houses over consolidated soil, and for these reasons called Venezia Nuova . The project led to the construction of twenty-three new city blocks, seven bridges over the canals, twenty-five streets and three squares (see Fig. 1a). Completed in the early 18th century, Venezia Nuova had to respond efficiently to the functions of storage and movement of merchandise. To this end, each lot was guaranteed a landing on a canal, so as to make it possible to dock boats (called “navicelli”) loaded with goods to store in the cellars under the road level, which were accessible through pulleys, slides and stairs. Above ground, the buildings were divided into further warehouses and service rooms on the ground floor and luxury residences on the upper floor. Goods could thus be transported to Pisa, Florence, Siena, and Lucca by boat through the Navicelli Canal and then the Arno river, the Ripafratta Canal, the river port of Empoli and the Elsa river, and delivered to destination by mule caravans. The goods thus reached the most inland places, or could be shipped onward by sea to other ports. The Venezia Nuova city quarter became home to many of the regions wealthiest merchants and most important consulates; there were residences of all classes, warehouses, shops, theaters, academies and services. 2. The system of canals and cellars in Livorno

1 . Information mainly drawn from Storia della città by C. Testa; Una passeggiata nel quartiere della Venezia Nuova by L. Pellegrino, M. De Vincenzi.