In The Name Of Allah. Report No ( 1) Arch Bridge. Mansoura University. Faculty Of Engineering. Civil Eng . Dept. Contents. 1- Overview. 2- How do the abutments support an arch bridge?. 3- Stone Arch Bridge. 4- Concrete Arch Bridge . 5- Precast Concrete Construction.
Report No ( 1)
Civil Eng . Dept.
2- How do the abutments support an arch bridge?.
3- Stone Arch Bridge.
4- Concrete Arch Bridge .
5- Precast Concrete Construction.
6- THE STONE ARCH BRIDGE .
7- THE KEYSTONE .
8- HOW TO BUILD AN ARCH .
9- Skew Arch Bridge .
10- THE END.
Arch bridges are one of the oldest typesof bridges and have great natural strength. Instead of pushing straight down, the weight of an arch bridge is carried outward along the curve of the arch to the supports at each end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out.
The Romans developed considerable skill in constructing arches and many of their structures remain intact today. However, they were not able to calculate the strength of their-arches although their knowledge of geometry inherited from the Greeks led them to adopt semicircular spans. Their arches were constructed
Today materials like steel and pre-stressed concrete have made it possible to build longer and more elegant arches, including a spectacular 1700 foot span in New River Gorge, West Virginia. (More typically, modern arch bridges span between 200-800 feet.)
Cut a strip of cardboard that\'s about one inch by 11 inches. Gently bend the strip so that it has a curve. Position the cardboard on a table so that it resembles an arch. Press down on the center of the arch. What happens to the ends of the cardboard?
Next, place a stack of books at each end of the arch. Press again. Now what happens? Notice how the stacks of books act as abutments, keeping the ends of the arch from spreading apart.
When supporting its own weight and the weight of crossing traffic, every part of the arch is under compression. For this reason, arch bridges must be made of materials that are strong under compression.
Constructing an arch bridge can be tricky, since the structure is completely unstable until the two spans meet in the middle. The method of construction of precast concrete arches is similar to the method of construction used during the Roman period.
Concrete arch bridge
The most common form of precast concrete bridge construction is with the use of the conventional precast bridge beams. Different types of precast concrete decks and their structural advantages have been dealt with other speakers on this course. The construction of these types does not in general require special techniques. Their construction will therefore not be considered.
Arch bridges are one of the oldest types of bridges and have been arounded for thousands of years. Arch bridges have great natural strength.
They were originally built of stone or brick but these days are built of reinforced concrete or steel. The introduction of these new materials allow arch bridges to be longer with lower spans.
These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out.
The Arch Bridge is very common. They were built with stone before iron and steel bridges were introduced. A good example is seen in the picture below. The Romans used arch bridges throughout Europe and many of them are still standing today as they are very strong.
The keystone is the most important stone in an arch bridge, without this stone the arch would collapse. The keystone holds the arch together.
Draw a stone arch and label the keystone. Explain why the Keystone is very important.
Before an arch can be built a wooden frame is built. This allows the stones to be put in position. The frame is removed after the stones are in position.