Constructing Bridges and Walls, Part 2 - Retaining Walls
Retaining walls are built to hold back earth and to keep it from moving. They provide stability.
The 28th / 31st Avenue Connector Bridge project includes three types of retaining walls for different purposes.
- Mechanically Stabilized Earth (MSE) Retaining Wall - This type of retaining wall is used at both ends of the 28th / 31st Avenue Connector Bridge. Its purpose is to help support the roadbed approaching the bridge.
This type of retaining wall is constructed of soil and stone in combination with artificial reinforcing materials such as high-density synthetics that are formed into a grid pattern and attached to concrete blocks. These blocks are visible on the outside of the retaining wall.
- Gravity Retaining Wall – This type of retaining wall is used when a low wall under 5’ to 6’ in height is needed. A gravity retaining wall can be seen near the north end of the project adjacent to the Urology Associates parking lot.
Gravity retaining walls are constructed of unreinforced concrete. Their strength and stability come for their own weight and the way that they are positioned against the soil.
- Cantilever Retaining Wall – This type of wall is used when walls higher than 5’ to 6’ are needed. Cantilever retaining walls have been constructed on the HCA property where the surface parking lots are being altered.
This type of wall is constructed of reinforced concrete. It is supported by a concrete slab footing that is several inches thick and is placed directly on the ground.