The Isaiah David Hart Bridge is a truss bridge

Truss bridge

A truss bridge is a bridge composed of connected elements which may be stressed from tension, compression, or sometimes both in response to dynamic loads. Truss bridges are one of the oldest types of modern bridges...

 that spans the St. Johns River

St. Johns River

The St. Johns River is the longest river in the U.S. state of Florida and its most significant for commercial and recreational use. At long, it winds through or borders twelve counties, three of which are the state's largest. The drop in elevation from the headwaters to the mouth is less than ;...

 in Jacksonville, Florida

Jacksonville, Florida

Jacksonville is the largest city in the U.S. state of Florida in terms of both population and land area, and the largest city by area in the contiguous United States. It is the county seat of Duval County, with which the city government consolidated in 1968...

. It is named after Isaiah Hart

Isaiah Hart

Isaiah David Hart was an American plantation owner and the founder of Jacksonville, Florida. Originally from Georgia, he began setting out the plans for the town in 1822 after moving to the area named Cowford. The Isaiah D. Hart Bridge over the St. Johns River in Jacksonville is named after...

, the founder of Jacksonville. It was designed by Sverdrup & Parcel

Sverdrup & Parcel

Sverdrup & Parcel was an American civil engineering company formed in 1928 by Leif J. Sverdrup and his college engineering professor John I. Parcel. The company worked primarily in a specialty field of bridges. Many of the company's projects were located in the St...

.

Details

The bridge has traditionally been painted green and is often referred to as "The Green Monster" by locals. The westbound end of the bridge delivers drivers to downtown Jacksonville or Martin Luther King Expressway, while the eastbound end sends motorists to Beach Boulevard. Daily traffic is 47,000 vehicles. The stretch of highway between downtown and Beach Blvd. is known as the Commodore Point Expressway, but more commonly referred to by locals as the Hart Bridge Expressway.

The truss is either a cantilever

Cantilever bridge

A cantilever bridge is a bridge built using cantilevers, structures that project horizontally into space, supported on only one end. For small footbridges, the cantilevers may be simple beams; however, large cantilever bridges designed to handle road or rail traffic use trusses built from...

 or a continuous truss bridge

Continuous truss bridge

A continuous truss bridge is a truss bridge which extends without hinges or joints across three or more supports. A continuous truss bridge may use less material than a series of simple trusses because a continuous truss distributes live loads across all the spans; in a series of simple trusses,...

, as it has been reported by different sources as each kind. Jackson Durkee listed the bridge as a cantilever truss in his 1999 report on longest spans. Alexander Svirsky publishes a copy of the National Bridge Inventory Database at NationalBridges.com, where the Florida Department of Transportation

Florida Department of Transportation

The Florida Department of Transportation is a decentralized agency charged with the establishment, maintenance, and regulation of public transportation in the state of Florida. The department was formed in 1969. It absorbed the powers of the Florida State Road Department...

 data lists the bridge as a continuous truss.

External links

• City of Jacksonville article about the bridges (PDF
  Portable Document Format
  Portable Document Format is an open standard for document exchange. This file format, created by Adobe Systems in 1993, is used for representing documents in a manner independent of application software, hardware, and operating systems....
  
  )