I understand that foundations are used in structures to support and spread the weight of the bridge over a large area. However I am struggling to understand why certain materials such as concrete are used in foundations over others. My first thoughts were based on how uplift may be effected.
Concrete is a strong, reasonably low cost, readily available, versatile construction material.
It lasts forever and keeps getting even stronger over time.
It can become into a very flexible, or very stiff part of the structure, depending on the type of reinforcement and their position.
It can be placed in a wide range of weather conditions and will last submerge under running corroding water.
It can be used almost all over the world from Antarctica to hottest arrid climates in the desert.
It can be modified, drilled into, attach brackets or hardware to to receive new configuration of superstructures.
It is responsible for some of the wonders in modern engineering and architecture in the world. Some examples are the highways in Europe, high-rises in Dubai and Hong Kong.
All are built on concrete foundations that withstand the harsh salty ocean waters, none of which would be possible without concrete foundations.