Title:
A Helicoidal Concrete Ramp
Author(s):
Gilbert H. Beguin
Publication:
Concrete International
Volume:
29
Issue:
7
Appears on pages(s):
37-42
Keywords:
post-tensioned concrete; prestressed concrete; ramp; torsion
DOI:
Date:
7/1/2007
Abstract:
Curved ramps typically have symmetric sections with outer and inner edges equally supported, making torsion effects minimal. The ramp described in this article, however, was supported only at discrete points around the outer edge, producing significant torsion that was further complicated by the ramp’s asymmetrical, open cross section. Prestressing allowed the segmentally constructed, curved structure to be continuous and provided a large increase in the section’s torsional resistance. The ingenious introduction of a balancing lever that applied torque to a main segment also helped avoid excessive torsional stresses.