Presentation on bridges
- 2. ADNAN ALI CHEEMA FA15-BCV 4A-003
- 3. BRIDGES
- 4. CONTENTS v What are bridges. v History of bridges. v Importance of survey in bridge construction. v Types of foundations for bridges. v classification of bridges. v types of bridges.
- 5. BRIDGES • Bridge is a structure that provides passage over obstacles such as valleys, rough terrain and water bodies. • These obstacles may be natural or manmade materials.
- 6. Historical background • For the first time bridges were used by first modern civilizations in Mesopotamia. • In the beginning bridges were very simple structures that were built from easily accessible natural resources- wooden logs, stone and dirt
- 7. HISTORY OF BRIDGES • Initial bridges were made of logs and stones. • • 100 B.C romans constructed first arch bridge. • • In 700 A.D great stone bridge of china was constructed. • • In 1900 truss bridge was introduced. • • In 1920, first suspension bridge was constructed. • • In 2000 pre stressed concrete bridge was constructed.
- 9. SURVEY FOR BRIDGE CONSTRUCTIONS• Bridge surveying is necessary to: 1. locate a site. 2. Obtain information for design. 3. plan the construction properly.
- 10. FOUNDATION • • Lowest and supporting layer is called foundation. There are two types of foundations. 1. Deep 2. Shallow •
- 11. TYPES OF FOUNDATION • Shallow foundation is a foundation that transfers loads to ground near the surface • some types of shallow foundation are: 1. Combined footing. 2. Mat footing. 3. Spread or isolated Footing. 4. Strip Footing. 5. Strap or cantilevered footing.
- 12. TYPES OF FOUNDATION Deep foundation is a type of foundation in which depth is much more than its width. Types of deep foundations : 1. Pile Foundation (cylindrical tubes are drilled and filled with concrete) 2. Pier Foundation (large excavated area filled with concrete) 3. Well Foundation or Caisson (hollow substructures constructed near construction area and sunk as a single unit).
- 15. On the basis of material Types of Bridges based on Materials 1. 2. Timber bridge 3. Masonry bridge 4. Steel bridge 5. R.C.C bridge 6. Pre stressed concrete bridge
- 16. Timber Bridge Bridges constructed using timber are called timber bridges. • These are generally constructed for short spans or as temporary bridges. • These are not useful for heavy loads.
- 17. Masonry Bridge • Masonry Bridge are constructed by using bricks or stones. • These are generally constructed for short spans and in low depth canals. Steel Bridges • Steel bridges are constructed using steel bars or trusses or steel cables. • These are more durable and bear heavy loads.
- 18. R.C.C Bridge • R.C.C bridges are constructed using reinforced cement concrete. • These are more stable and durable. They can bear heavy loads and are widely used nowadays. .
- 19. Prestressed Concrete Bridge • If concrete material is placed under compression before applying the loads, then it is called as prestressed concrete. • To construct pre stressed concrete bridge, pre-stressed concrete blocks are arranged as deck slab with the help of girders.
- 20. Classification on the basis of span • • Culvert bridge • Minor bridge • Major bridge • Long span bridge
- 21. On the basis of span • On the basis of span bridges have following types: 1. Culvert bridge: When the bridge span length is below 6meters then it is called as Culvert Bridge.
- 22. 2. Minor Bridge If the bridge span length is in between 8 to 30 meters, then it is called minor bridge. • Major Bridge • For major bridge, the span is generally about 30 to 120 meters.
- 23. • Long Span Bridge When the span of bridge is more than 120 meters then it is termed as long span bridge.
- 24. TYPES OF BRIDGES
- 25. TYPES OF BRIDGES Main types of beams are: 1. BEAM BRIDGE: Consists of a horizontal beam supported at each end by piers or abutments. • The weight of the beam pushes straight down on the piers. • The force farther apart its piers, and the bridge is not constructed too long. • Beam bridges rarely span more than 250 feet.
- 27. ARCH BRIDGES: • An arch bridge is a type of bridge whose abutments at each end shaped as a curved arch. • they have a very strong structure and they transfers loads to the abutments along its curve. • Arch may be given above or below the deck. • It can have a span of up to 800 ft. • Examples of arch bridge is The Hell Gate Bridge in New York
- 29. Suspension Bridges:Suspension Bridges: A suspension bridge is a type of bridge in which the deck is hung below by suspension cables on vertical suspenders. • these bridges can have a span of 2000 to 7000 ft.these bridges can have a span of 2000 to 7000 ft. • Base of suspension bridge is supported by trusses.Base of suspension bridge is supported by trusses. • golden gate bridge calefornia is an example.golden gate bridge calefornia is an example. •
- 30. CABLE STAYED BRIDGE • The cable-stayed bridge seems same to the suspension bridge but is different. • In cable stayed bridge the cables run directly from the roadway up to a tower, forming a unique "A" shape
- 31. Truss bridge: A truss bridge is a bridge whose load-bearing superstructure is composed of a truss. • generally trusses are made of steel.