U n c o n v e n t i o n a l C o n s t r u c t i o n T e c h n o l o g y
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As shown by investigations of walls, carried out by means of appropriate removal of
plaster, masonry types have proved to be fairly consistent, with a few exceptions, such
as the basement of the west building and other recent buildings.
Generally the mortar used is made up of an aggregate of very fine particle-size
distribution, with magnesian lime-based binder material with hydraulic characteristics,
probably taken from the south east of the Euganean Hills.
The recovery project
The recovery project was born in accordance with specific rules imposed by the
designers and the client. First, it envisaged the preservation of the original features so as
to limit, as far as possible, work on the building and ensure a project which was
sustainable and respectful of the pre-existing building.
Therefore there was the desire to propose renewable technology and a low
environmental impact energy use. Discovering that the original porch was closed
certainly offered a good reason for designers to proceed in that direction.
The problems related to the reopening of the gallery derive from the non-load bearing
properties of the walls and foundations, especially if considered in relation to the loads
required by new uses.
The project involves the construction of university classrooms and thus takes into
account the location of the building (the historic centre of Padova) certainly optimal for
reducing the impact due to private vehicles allowing all users to make use of public
transport.
A further problem is the lack of original capitals, as these were removed long ago.
For this reason, the area of confluence of the two adjacent arches must be supported by
a new capital of considerable rigidity to prevent sagging and deformation, which might
cause instabilities in the masonry known to be very rigid and not able to resist traction
stress.
In relation to expected new loads and overloads, and to meet the static requirements,
also considering geotechnical report data on the type, size and texture of individual
layers of the soil, it was decided to opt for a new system of deep foundations, made up
of small micro diameter piles (diameter about 22-25 cm), able to guarantee absolute
minimum subsiding (and therefore differential subsiding) in the structures that are
supported by them.
The proposed micropile has an armour made of steel pipe
∅
101.6 mm, with a thickness
of 8 mm and a diameter of 22-25 cm. The actual lengths range from 12 m and 15 m. The
tip of the micropile is positioned on the same deposit of sand placed at -15 m.
To complete the structure of the foundation, micropiles are mutually connected by a
concrete slab reinforced with variable thickness between 15 and 20 cm depending on
the loads present (Fig. 45).
