peter rice

The choice of the structural system for
a new church is a major element of
the design. The important nature of the
Padre Pio church, its size and location,
calls for a very particular structural
solution for supporting the roof.
For the Padre Pio church it is
proposed to use a series of arches in
natural stone to provide a distinct
primary structure from which a
secondary roof structure will be
supported. The arches will be set out
on a radial plan converging towards
a focus at the altar of the church. Two
sets of primary arches, inner and
o'uter, will be used . Inner arches, with
approximately 50m spans, will fan
out from the focus point to support the
roof over the central part of the
church whilst a set of smaller outer
arches will span over the outer part of
the floor, which will vary in width
around the central zone.
Although largely ignored as a
possible choice for most
contemporary buildings, natural stone
can have strength and durability
characteristics which make it a valid
modern structural material if it is used
properly and where geometric forms
are not constrained by conventional
building requirements. The successful
cathedrals built in stone demonstrate
the strength of natural stone and the
types of form for which it works best.
Essentially, natural stone is a material
which should be used for its good
compressive strength. The avoidance
of tensile strains within stonework can
be achieved by finding a suitable
geometry which allows load
transmission by primarily compressive
thrust. Thus, for larger spans, the arch
form is an obvious preference for
stone structures.
The roof system between the arches is
proposed to be of timber
construction. A variety of options
exists for the precise geometry and
structural configuration for this part of
the roof and the final choice of
construction may be influenced partly
by environmental and acoustic
considerations within the church. The
roof level structure will be used to
provide the lateral stability necessary
to the primary arches. These
stabilising forces will be transmitted
via a three-dimensional intermediate
transfer structure between the arches
and roof.
The project combines the strong
traditions of material use and
craftsmanship associated with church
buildings, with the application of the
most modern technology to structural
design and construction.
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