HOW BRIDGES ARE BUILT?


As a daily commuter, we use bridges almost every day. We see bridges not only in major cities, but also in rural areas. Bridges are important not just for traveling from point A to B, but also in connecting people’s lives, hopes, and dreams. But ever wondered how bridges are built? The finish product may look simple; however, each bridge is built with painstaking planning and tedious labor.
In this post, let us look at the basic steps on how a bridge is built.

PREPARATION:-

The preparation phase is the most important part of bridge construction. It is a must that you identify the place where the bridge will be built. After that, surveyors should determine whether a bridge is really needed or not.
Bridges can be constructed in different types of natural obstacles. Though it is commonly built over a body of water, it can also be built over valleys, roads, and even over another bridge.
Moreover, before the construction should begin, the necessary papers and documents should be submitted to the local government officials. This is to ensure that no historic structure or geological formation would be affected by the construction.
When the proposed plan is approved, then design will be the next phase.

DESIGN:-

As the need for a bridge is identified, the next step would be planning its design. Since there are different designs to choose from, engineers and architects should be able to look into the construction area and identify the best design that will fit the current and future need.
The most basic and common designs used around the globe is the truss, cable-stayed, suspension, and arch model. Each of these designs has its unique features, advantages, and drawbacks. The engineers and architects should be able to look into the construction site and collect information that will help make the right design selection. Not only that, the weather pattern of the area, along with the amount of expected traffic from vehicles and people and the availability of construction materials should be considered as well.
The arch bridge can be an ideal choice if the foundation of the earth is tough and strong enough. Thus, it needs natural rock and stone to be already in place.
The beam bridge is the most common bridge design used today; since it is relatively cheaper, easier to construct, and more functional. However, beam bridges have limited opening that can be crossed.
Suspension bridges are more expensive, delicate, and complicated. It can be built over a great distance.
Finally, the cable-stayed bridge is the newest design. The main support of the bridge is from the center sustained by the large ship-like mast. The longer the bridge, the more mast is needed.

CONSTRUCTION:-

Finally, when the preliminary design and plan have been approved, construction will proceed. Again, the construction method will be done according to the design of the bridge. Some methods of construction may involve bringing all the construction materials in the area, while others are brought in the area as pre-formed materials. A typical bridge construction may take less than a year to even a decade.

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