A LANDMARK CONCRETE ARCHED BRIDGE

摘要

The Greater Toronto Area (GTA) hosts some of the most scenic routes and landscapes in all of Ontario and Canada. The global concept of sustainability and environmentally-friendly structures has its aesthetics dimension towards blending with nature. For millennia, arched bridges have been some of the most effective structural systems that serve both function and appearance. The viaducts built by the Romans followed by the structures of both medieval and Renaissance periods along with modern bridges are standing examples for how arched bridges can be in great harmony with nature. This paper presents a concrete arch bridge that is portrayed as a landmark in the picturesque area of the subject project within the GTA. The bridge will carry both vehicular and pedestrian traffic over a water stream and a trail along the side of the stream. The proposed single span arched bridge will accommodate two lanes of vehicular traffic and a sidewalk for pedestrian traffic on each side of the deck. In addition to satisfying the high profile aesthetics criterion of the bridge, two bridge alternatives are investigated (a Bow-String and a Fixed Arch) in order to achieve the most economical and efficient design. The Bow-String alternative involves an arch above the deck with hangers placed at set intervals, acting as tension members to transfer the load from the deck to the arch. The second alternative, Fixed Arch, is comprised of an arch below the deck with posts in-between, acting as compression members transferring loads from the deck to the arch. Both options are evaluated from the technical, financial and aesthetics aspects to obtain an optimum landmark bridge structure.