Civil arch bridge is carried outwards along

Civil engineering is one type of engineering that deals with constructed environment such as, designing and overseeing construction and maintenance of buildings, roads, bridges etc. The purpose of this report is to discuss the different types of bridges and stating their advantages and disadvantages. The report will discuss the materials used in constructing different types of bridges and the style and shapes used to construct a bridge also, discuss the approximate cost of each design. A bridge design project follows this report and it represent one type of bridge design that would withstand heavy weight with standard amount of materials provided.  There are several types of bridge designs. They vary depending on the material and shapes used in constructing a bridge design. Some bridges have been used centuries ago. Some are still being used nowadays.  Types of bridges: Arch bridge:  Arch bridges are one of the oldest bridge structures and have been around for thousands of years. Arch bridges were first built by ancient Romans. The load on an arch bridge is carried outwards along the curve of the bridge to the supports at each end. The supports are also called abutments. In the old days stone was used in constructing arch bridge. If a load was placed on the bridge, the load is distributed and each stone pushes on the one next to it until the load is applied to the abutments on each end. Materials used in construction of arch bridges compact closer and closer together during time and use giving it a solid foundation. On the other hand, they take a long time and large amount of labor to build an arch bridge. Regular maintenance is required to ensure that the bridge is safe and stiff. This includes repairing damages caused by any types of storms and painting the bridge to prevent rusting. Less amounts of materials are required comparing to other bridge designs and how load is distributed, this keeps it in use until now.   The materials used in constructing an arch bridge, has changed over time. In the Roman age, arch bridges were built of stone or bricks. After the production of steel, arch bridges are built of reinforced concrete and steel. Steel has properties that makes it suitable for bridge construction. Steel has a yield strength of maximum 550MPa which means that it can withstand high amount of stress without causing plastic deformation. It is affordable. Concrete has compressive strength of 20-40 MPa. Difference between steel arch bridge and stone arch bridge is that steel is stronger under tension whereas stone bridges are stronger under compression. This what makes them suitable for designing an arch bridge. in modern days steel is used more in constructing an arch bridge because it is cheaper to manufacture and can be used for longer distances than a stone bridges. Arch bridges attract tourists due to their attractive view. This can benefit the country’s economy. An example of an arch bridge that attracts tourists is (The Harbour Bridge) in Sydney, Australia.  Beam bridge: Beam bridges are the simplest and oldest structural forms of bridge designs. A beam bridge is a beam supported by an abutment at each end. The idea of beam bridges came from nature. Ancient people saw a tree fallen across a stream and they imitated the idea and started building bridges classified as beam bridges. At the start of beam bridges, timber was used across a stream and the abutments were made of stone. After centuries of making beam bridges, wooden beams were replaced with steel beams that have higher yield strength and can with stand higher loads without failure. Constructing a beam bridge using timber faced a few issues such as availability and cost. Also, pests that ate wood were risking the bridge which require regular maintenance. Engineers started painting timber with a material to avoid termites. This material is dangerous and causes lung cancer.  beam bridges are helpful for short spans and reasonable cost. Requires shorter time to build a beam bridge than building any other bridge designs. They are not used over long distances because they would not withstand a heavy load unless they use abutments in between the side supports. In this case a different bridge design could be used that can withstand a heavier load with standard amount of materials that can save a lot for a country. Engineers figured out different shapes created in the beam. The beams have shapes L and T beams.   Truss bridge Truss bridge is one kind of bridge designs that are based on connected materials in a triangular shape. They are very rigid structure as they