Structures
Both bridges are located adjacent to each other along Highway 82 approximately one-half mile (1 km) east of the traffic circle where Maroon Creek Road, the access route to the Maroon Bells leaves to the south, just outside the developed portion of the city of Aspen. Due west of that are the remnants of the Holden Mining and Smelting Co. facility, also listed on the National Register as a historic district. The city's corporate limit follows the bridge, with the land to the north within Aspen and the south just Pitkin County. The creek flows through a deep gorge below, roughly 1 mile (1.6 km) upstream of where it drains into the Roaring Fork River to the north. On all corners but the southeast are golf courses; that corner has a small residential neighborhood of modern construction.
A steel safety net has been installed since construction of the new bridge in the two-foot (60 cm) gap between the bridges. The original bridge has 20 plate girder spans supported by nine tapered steel piers. Two deep deck girders, iron plate webs with riveted angle flanges and web stiffeners, carry the road. The piers are made up of two bents, their legs made of two back-to-back steel channels with cover plate and double lacing. They are braced by tiers of compression beams and tension eyebars. At the ground they are supported by masonry piers.
The new bridge is 620 feet (190 m) long, 30 feet (10 m) shorter than its older neighbor. It consists of a 270-foot (82 m) main span with two 170-foot (52 m) end spans. Its deck is formed from a 73-foot–wide (22 m) single-cell box girder at a constant depth of 13½ feet (4.1 m) with ribbed elements supporting the long slab spans. Most segments are 15 feet (4.6 m) long, with a deck rib 5 feet (1.5 m) from the leading edge. The segments are laid out on 25-foot (7.6 m) pier table, with eight in the main cantilever, ten in the side spans and a 5-foot segment closing the two cantilevers.
They are supported by A-shaped concrete piers with a capital at the top flared outward at the same angle as the outriggers on the historic bridge. The piers themselves are a constant 10 feet (3 m) in the direction of the bridge but stretch from 6 feet (2 m) at the top to 10 feet (3 m) at the bottom. Their footings are on 12 4-foot–wide (1.2 m) drilled 20 feet (6 m) deep into the bedrock. The abutments on either side of the gorge are supported by 72 8-inch (200 mm) micropiles designed to support 150 kips each.
Read more about this topic: Maroon Creek Bridge
Famous quotes containing the word structures:
“It is clear that all verbal structures with meaning are verbal imitations of that elusive psychological and physiological process known as thought, a process stumbling through emotional entanglements, sudden irrational convictions, involuntary gleams of insight, rationalized prejudices, and blocks of panic and inertia, finally to reach a completely incommunicable intuition.”
—Northrop Frye (b. 1912)
“If there are people who feel that God wants them to change the structures of society, that is something between them and their God. We must serve him in whatever way we are called. I am called to help the individual; to love each poor person. Not to deal with institutions. I am in no position to judge.”
—Mother Teresa (b. 1910)
“The American who has been confined, in his own country, to the sight of buildings designed after foreign models, is surprised on entering York Minster or St. Peter’s at Rome, by the feeling that these structures are imitations also,—faint copies of an invisible archetype.”
—Ralph Waldo Emerson (1803–1882)