Bridges are essential structures that are often built over water bodies, valleys, or other obstructions to facilitate the smooth movement of vehicles and pedestrians.


In this article, we will discuss the basic components and functions of a bridge, as well as its types based on length, force characteristics, and structural system.


A complete bridge comprises several basic components, namely the bridge span structure, pier part, bearing part, abutment part, and pier foundation. Without these components, a bridge cannot be considered complete.


The bridge span structure is the part that spans across the river, valley, or any other structure.


Its primary role is to connect the bridge to vehicles, pedestrians, and other means of transportation.


Bridge piers, on the other hand, are the columns that support the bridge span structure on the river or bank.


They are responsible for bearing the downward force of the bridge span part and transmitting it to the foundation to maintain the stability of the bridge.


The bearing part is the force transfer device that connects the bridge span structure to the pier or abutment support.


Its role is to transfer a large load and ensure that the bridge span structure can produce a certain amount of displacement or strain.


The abutment part, located at the end of the bridge support part, plays a similar role to the abutment.


It bears the embankment of the earth's pressure and maintains the stability of the embankment.


The tapered slopes, retaining walls, and other protective works are often constructed on both sides of the abutment.


The pier foundation is the structure that ensures the safety of the bridge pier and transmits the load to the foundation.


It is the lowest part of the entire bridge, from which the load is transmitted to the earth.


There are various types of bridges classified based on their length, force characteristics, and structural system.


According to the length, bridges are classified as small, medium, large, and special bridges.


Based on force characteristics, they can be categorized as beam bridges, arch bridges, suspension bridges, cable-stayed bridges, rigid bridges, and combined system bridges.


The four basic structural systems of bridges are beam bridge, arch bridge, rigid frame bridge, and cable-bearing bridge.


Beam bridges use beams as the load-bearing structure, relying on their bending capacity to bear the load.


Arch bridges, on the other hand, use arch ribs or arch rings as the main load-bearing structure, mainly to bear the pressure.


Rigid frame bridges, due to the rigid connection between the beam and the column, rely on the bending stiffness of the column to bear the load, making it a compression-bending member and a structure with thrust.


Finally, cable-stayed bridges combine a pressure-bearing tower, tension-bearing cable, and bending-beam body as their structural system.


Bridges are essential structures that facilitate the smooth movement of vehicles and pedestrians over water bodies, valleys, and other obstructions. Understanding the basic components and types of bridges is crucial for ensuring their safety and efficiency in transportation.