Bridge foundations are crucial components in bridge construction. It's important to know that there are several types of bridge foundations commonly used, each with distinct uses and requirements. For example, a spread footing foundation can only be used on certain types of soil.
Typically, bridge construction utilizes precast concrete to expedite the process. Precast concrete is a popular choice in construction projects due to its practicality. If you're unfamiliar with the types of bridge construction and foundation varieties, keep reading to learn more.
Types of Bridge Foundations
The primary function of a bridge foundation is to support the bridge’s load. Essentially, there are two types of bridge foundations: shallow foundations and deep foundations.
A shallow foundation relies on the soil for most of its load-bearing capacity. In contrast, a deep foundation involves embedding the foundation structure into the ground, relying on the friction at the foundation's depth to support the load.
Based on these two categories, several other types of foundations are commonly used in bridge construction projects. Here are some bridge foundation types you should know:
1. Spread Footing
Spread footing falls under the shallow foundation category. This type consists of two components: the footing and the stem. The bridge’s load directly transfers to the stem, which is made of concrete. The stem then distributes the load to the footing. The footing, in turn, spreads the bridge’s load across a wider area.
It's important to note that this foundation type isn’t suitable for all soil conditions. Additionally, preparing the concrete pour for a spread footing must be done manually due to the large volume of concrete required. Despite this, spread footing has some advantages, such as greater durability because the bridge load can be evenly distributed.
2. Raft Foundation
A raft foundation is suitable for areas with low soil-bearing capacity. This type of bridge foundation is common in regions with soft clay, mud, or where hard soil is not available at a certain depth. Additionally, this foundation is commonly used in bridge projects that bear high loads.
3. Driven Piles
Next is the driven piles foundation, also known as a pile foundation. This is a deep foundation type where piles are driven into the ground to support the bridge’s load. The piles can be made of steel, concrete, or wood.
One advantage of this foundation type is its versatility across various soil conditions. It’s also cost-effective. However, the installation process can be disruptive to the surrounding area due to the noise and vibrations generated.
4. Drilled Shaft
The drilled shaft is another type of deep foundation. Creating this foundation involves drilling a hole into the ground, which is then filled with concrete and reinforcement. The shaft is embedded deep enough to reach bedrock, providing high load-bearing capacity.
This foundation’s advantages include strong lateral and axial load resistance. However, the costs associated with this foundation type can be high.
Types of Bridge Construction
Apart from foundations, bridges can also be classified based on their construction types. Here are some bridge construction types you should be familiar with:
1. Truss Bridge
The first type is the truss bridge, which uses a triangular frame. This framework enhances the bridge’s strength and distributes the load evenly across the structure, preventing collapse due to excessive load on any single area.
2. Beam Bridge
The next type is the beam bridge, commonly known as a girder bridge. This bridge uses concrete girders as its primary material. Typically, beam bridges have a horizontal structure supported by vertical piles to bear the load.
Beam bridges are often used to connect two areas that are relatively close, such as crossing a river.
3. Arch Bridge
As the name suggests, an arch bridge features a curved, bow-like shape. Arch bridges are known for being material-efficient. Despite this, they offer higher durability compared to beam bridges or truss bridges.
In the past, these bridges were made from simple materials like bricks and wrought iron. However, modern arch bridges are constructed from prestressed concrete and steel, allowing them to span greater distances. This type of bridge is ideal for areas with hard soil, providing a solid foundation support.
4. Cable Stayed Bridge
Cable-stayed bridges are commonly used in earthquake-prone areas because of their low center of mass. The construction relies on steel cables to support the bridge’s load. Typically, cable-stayed bridges span lengths between 100 meters and 600 meters.
The cables are anchored to towers on the bridge’s pillars. While these bridges can withstand axial tension forces, they are susceptible to wind forces.
5. Suspension Bridge
Similar to cable-stayed bridges, suspension bridges also use steel cables to support the bridge’s load. The difference is that, in suspension bridges, the cables are not connected to towers.
This means suspension bridges can sway easily in strong winds or under heavy loads, making them unsuitable for heavy traffic or use during bad weather. However, they can be built to span up to 1,400 meters.
That's an overview of various bridge construction types and foundation varieties. In bridge construction, precast concrete is often used for its practicality and efficiency. If you’re looking for precast concrete for bridge construction or other projects, you can rely on Merah Putih Beton products.
Merah Putih Beton offers a wide range of precast concrete options, including PC-I Girder. PC-I Girder from Semen Merah Putih features concrete quality of K550-K800 based on cube tests. The PC-I Girder comes in lengths ranging from 10-5 meters, with several height options: 0.9 m, 1.25 m, 1.6 m, 2.1 m, and 2.3 m.
If you have further questions about other products from Semen Merah Putih, don’t hesitate to contact us. With Semen Merah Putih, make your structures stronger and more durable.
