What is deck type plate girder?
What is deck type plate girder?
Overview. In a plate girder bridge, the plate girders are typically I-beams made up from separate structural steel plates (rather than rolled as a single cross-section), which are welded or, in older bridges, bolted or riveted together to form the vertical web and horizontal flanges of the beam.
What is deck girder on bridge?
Girder bridges are the simplest bridge type in structure and consist of steel beams shaped to an I-section or box section, called a plate girder bridge or a box girder bridge, respectively. Girder bridges are comprised of deck slabs, on which vehicles and people pass, and of main girders supporting the deck slabs.
What is through type plate girder?
For long or heavily loaded bridge spans, restrictions on depth of structural system imposed by vertical clearances under a bridge generally favor use of through construction. Through girders support the deck near their bottom flange.
How do you use a plate girder?
A plate girder is a built up I-beam section, used to carry heavy loads which cannot be carried economically by rolled I-sections. It is made by riveting or welding the steel plates in I-beam shape.
What is deck type and through type plate girder bridge?
• Deck-type bridges refer to those in which the. road deck is carried on the top flange or on top of the supporting girders. • Through type bridge – The carriageway rests at. the bottom level of the main load carrying. members.
What is stiffener plate?
Stiffeners are secondary plates or sections which are attached to beam webs or flanges to stiffen them against out of plane deformations. Almost all main bridge beams will have stiffeners. However, most will only have transverse web stiffeners, i.e. vertical stiffeners attached to the web.
Why plate girders are used?
The purpose of the plate girder is to build a beam that is larger than anything that can be built by a steel mill or factory. 5. The size and shape of the girder allows builders to construct structures that are much longer and heavier duty.
What kind of bridge is supported by plate girders?
Deck-type plate girder bridge. In the deck-type bridge, a wood, steel or reinforced concrete bridge deck is supported on top of two or more plate girders, and may act compositely with them. In the case of railroad bridges, the railroad ties themselves may form the bridge deck, or the deck may support ballast on which the track is laid.
How is the length of a plate girder determined?
Plate girders are usually prefabricated and the length limit is frequently set by the mode of transportation used to move the girder from the bridge shop to the bridge site. Anatomy of a plate girder.
Can a triangulated bracing be used on a girder bridge?
Triangulated bracing as shown in Fig. is provided for deck type of plate girder bridges to increase lateral stability of compression flange. But, it can not be adopted for the half-through or through girder bridges because it interferes with functions of the bridge.
What should be used in a railroad bridge?
If a structure is unusual in some respects, designers should use their best engineering judgment in selection of proper design criteria. Most railroad companies permit and prefer high strength bolted or shop welded steel plate girders, reinforced concrete or prestressed concrete members in bridge construction.