Usually decorated with
fretwork or relief ornamental motifs, the pulvino reaches its maximum expression in the
Byzantine architecture; some examples can be found in the early Christian architecture of
Ravenna. Its particular convex shape gives the pulvino the structural function of concentrating the tensions generated by the loads above it and passing the tensions on the column located below the capital. An example can be seen in
the church of San Lorenzo in Florence designed by
Filippo Brunelleschi around 1420. There he resorted to additional segments of entablature improperly defined as "Brunelleschian nut". The pulvino in this case created a balanced entablature, on which the round arches are set. ==Modern engineering==