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4.1 Primary structure: arches and columns
The primary structure of the platform canopy consists of twenty parabolic twin
steel arches.
The outer ten arches at each side span 52 m, the inner ten arches span 39 m.
The arches are composed of 3 or 4 longitudinal sections of 13.8 m, in horizontal
projection, which consist of two half-bent HEM or HEB 200 sections.
The sections are cut in half longitudinally and pre-bent in the workshop. Next
they are welded together with rectangular plates of 10 to 15 mm thickness, and a
variable height of 30 to 50 cm. The plates at the ends of the 13.8 m long parts are
moment resistant in horizontal projection.
Both pre-bent arches are placed at a 36° angle. To assure adequate stiffness of the
double parabolic arch, the two arches are joined together every 3.25 m. The twin
arches are specifically designed to deform vertically under thermal expansion/
contraction stresses.
metal plate
metal plate Plate to be moved
10mm from the edge
of the roof plates
construction joint
details 3 or 5
roof platessee plan exe 05/19
construction joint
details
1 or 1a
Plate to be moved
10mm from the
edge of the roofplates
roof platessee plan exe 05/19
metal plate
metal plate