Robert Maillart's Curved Concrete Arch Bridges

Starting from a description of his four curved concrete arch bridge projects it is shown how Maillart adapted his deck-stiffened arch concept to allow for a horizontally curved deck. Based on this review possible extensions of Maillart's concepts are discussed. For shortand medium-span curved bridges the advantages of longitudinally fixed frame systems with slender inclined columns and post-tensioned deck beams are pointed out. For long-span curved bridges, arch systems with post-tensioned deck beams and generously spaced columns or cross walls are found to offer similar advantages provided that the end supports are fixed and deck and arch are appropriately connected at midspan. For moderate live to dead load ratios an interesting variant is obtained by using a suspension cable instead of an inclined arch and by attaching the hangers along the inner edge of a suitably prestressed deck beam that is clamped at the abutments.