A girder bridge is a bridge that uses girders as the means of supporting its deck . The two most common types of modern steel girder bridges are plate and box.
17-674: The Doran Memorial Bridge is the twin pair of steel girder bridges that carry eight lanes of road traffic on Interstate 280 over San Mateo Creek near Hillsborough, California in San Mateo County . The Doran Memorial Bridge was originally known as the San Mateo Creek Bridge according to Caltrans plans. It was named the Eugene A. Doran Memorial Bridge in 1969, after the Hillsborough police officer who
34-628: A "Pedestrian Day" was held on May 25, with more than 30,000 crossing the new span on foot. It won the Medium Span, High Clearance category in the 1970 AISC steel bridges contest. Markers commemorating Eugene A. Doran and the AISC award are at the Crystal Springs Safety Roadside Rest Area off northbound I-280, approximately 1 ⁄ 2 mile (0.80 km) north of the bridge itself. That stop also features
51-827: A 22 ft-high (6.7 m) statue of Junipero Serra . The Doran Memorial Bridge was featured on the cover of the 1972 Highway Statistics report published by the Federal Highway Administration with other recently completed major structures, including the Verrazano-Narrows Bridge , the Chesapeake Bay Bridge-Tunnel , and the Cowlitz River Bridge. The bridge was designed by Caltrans architect Warren S. Ludlow, engineers Robert Cassano and Delmar Janson, with assistance from Mario J. Ciampi . Ciampi
68-466: A combination of both. The concrete elements may be reinforced or prestressed . Such modern bridges include girder , plate girder , and box girder bridges, all types of beam bridges. Types of construction could include having many beams side by side with a deck across the top of them, to a main beam either side supporting a deck between them. The main beams could be I-beams , trusses , or box girders . They could be half-through , or braced across
85-498: Is concealed by a slanted panel on either side. Bids were opened on April 7, 1965, for the stretch of freeway including the San Mateo Creek Bridge. To minimize impact on the gorge below, materials were lowered from a "high line" built between towers on the adjoining cliffs. It is next to the 1888 Crystal Springs Dam , which was (at the time of its completion) the largest concrete structure in the world. Construction of
102-423: Is everything from the bearing pads, up - it is what supports the loads and is the most visible part of the bridge. The substructure is the foundation which transfers loads from the superstructure to the ground. Both must work together to create a strong, long-lasting bridge. The superstructure consists of several parts: The substructure is made of multiple parts as well: Beam bridge Beam bridges are
119-408: Is no longer a true girder bridge. Girder bridges have existed for millennia in a variety of forms depending on resources available. The oldest types of bridges are the beam , arch and swing bridges, and they are still built today. These types of bridges have been built by human beings since ancient times, with the initial design being much simpler than what we utilize today. As technology advanced
136-461: Is opposed to viaducts using continuous spans over the piers. Beam bridges are often only used for relatively short distances because, unlike truss bridges, they have no built in supports. The only supports are provided by piers. The farther apart its supports, the weaker a beam bridge gets. As a result, beam bridges rarely span more than 250 feet (80 m). This does not mean that beam bridges are not used to cross great distances; it only means that
153-462: Is typically used to refer to a steel beam. In a beam or girder bridge, the beams themselves are the primary support for the deck, and are responsible for transferring the load down to the foundation. Material type, shape, and weight all affect how much weight a beam can hold. Due to the properties of the second moment of area , the height of a girder is the most significant factor to affect its load capacity. Longer spans, more traffic, or wider spacing of
170-404: The beams will all directly result in a deeper beam. In truss and arch -style bridges, the girders are still the main support for the deck, but the load is transferred through the truss or arch to the foundation. These designs allow bridges to span larger distances without requiring the depth of the beam to increase beyond what is practical. However, with the inclusion of a truss or arch the bridge
187-502: The first pier began in January 1966. Girder bridge The term "girder" is often used interchangeably with "beam" in reference to bridge design. However, some authors define beam bridges slightly differently from girder bridges. A girder may be made of concrete or steel. Many shorter bridges, especially in rural areas where they may be exposed to water overtopping and corrosion, utilize concrete box girder. The term "girder"
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#1732791380318204-401: The methods were improved and were based on the utilization and manipulation of rock, stone, mortar and other materials that would serve to be stronger and longer. In ancient Rome , the techniques for building bridges included the driving of wooden poles to serve as the bridge columns and then filling the column space with various construction materials. The bridges constructed by Romans were at
221-470: The simplest structural forms for bridge spans supported by an abutment or pier at each end. No moments are transferred throughout the support, hence their structural type is known as simply supported . The simplest beam bridge could be a log (see log bridge ), a wood plank , or a stone slab (see clapper bridge ) laid across a stream. Bridges designed for modern infrastructure will usually be constructed of steel or reinforced concrete , or
238-496: The time basic but very dependable and strong while serving a very important purpose in social life. As the Industrial Revolution came and went, new materials with improved physical properties were utilized; and wrought iron was replaced with steel due to steel's greater strength and larger application potential. All bridges consist of two main parts: the substructure, and the superstructure. The superstructure
255-578: The top to create a through bridge . Because no moments are transferred, thrust (as from an arch bridge ) cannot be accommodated, leading to innovative designs, such as lenticular trusses and bow string arches , which contain the horizontal forces within the superstructure . Beam bridges are not limited to a single span . Some viaducts such as the Feiyunjiang Bridge in China have multiple simply supported spans supported by piers. This
272-517: Was commissioned to design freeway structures for I-280 by the Division of Highways in 1963. Four arched concrete piers support the twin girder bridges. They use modified Gothic arches ; the finish was left in the natural concrete color, and the surfaces were contoured to help them blend into their surroundings. The twin bridges contain five parallel welded steel girders and are connected by a 22-foot (6.7 m) wide concrete slab. The structural steel
289-606: Was killed near the site on August 5, 1959; Doran's widow attended the ribbon-cutting ceremony on May 28, 1969. In 2004, the bridge was rededicated as the Officer Eugene A. Doran and Marine Lance Corporal Patrick M. Doran Memorial Bridge to include his son, Patrick, who died in Vietnam on February 18, 1967 while serving in the United States Marine Corps . Prior to the opening ceremony on May 28, 1969,
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