FOLDED SLAB ROOFS
• A thin-walled building structure of the shell type
• Movable form work can be employed.
• Form work required is relatively simpler.
• Design involves simpler calculations.
• Folded plate consumes more material than shells.
Folded slab roof
• Modern folded plate structures are typically
made of cast in site or precast reinforced
concrete, or steel plate.
• Doubly curved surface- shape of a saddle.
• It has a convex form along one axis and
concave form on along the other.
• Easy to construct using a series of straight
• Constructed using concrete.
• The curvature reduces its tendency to buckle
in compression and achieves stiffness.
• Series of parabolas stung together.
• The use of reinforcing steel in the upward
curvature of the parabola allows for the
tensile forces to flow into first the neutral sag,
or catenary then the thrust of the forces flow
into the compression on the downward
• Both the axial parabolas are compressed and
A paraboloid is a particular kind of three-dimensional
surface. In the simplest case, it is the revolution of a
parabola along its axis of symmetry. This kind of surface
will open upwards in both sideways dimensions. A
hyperbolic paraboloid will open upward in one dimension
and downward in the other, resembling a saddle. Like in a
two-dimensional parabola, scaling factors can be applied
to the curvature of a paraboloid.
y = x2
• TWA terminal,NYC Intl. Airport
The variants of Paraboloids are:
•Elliptical paraboloid (silmilar to paraboloid)
A saddle-shaped quadric surface whose sections by
planes parallel to one coordinate plane are
hyperbolas while those sections by planes
parallel to the other two are parabolas if proper
orientation of the coordinate axes is assumed
In simple words, I is a combination of hyperbolae
and parabola within a single entity.
•Lee Valley Velo Park
•House by James R. Mowry