December 28, 2020
The purpose of all precast concrete retaining walls is to hold soil behind them. However, the specific requirements will differ depending on the project. Concrete retaining walls can range from small landscape stone walls to surround a garden to enormous soil-retaining projects along a highway. Others can help control erosion from heavy rains or create a terraced yard to minimize maintenance. When you start the initial planning, there are a few considerations that will affect the material and type of retaining wall you build. Below we look at four of them.
Location:
When choosing a location for your retaining wall structure, make sure you have a detailed understanding of guidelines and both over the ground and underground utilities including storm water management systems and irrigation system. Additional factors to consider about the region may include:
If your retaining wall is on a slope, where will you store extra infill that should be brought to the site? If you are cutting into a hillside, where will the abundance soil be stored?
Natural drainage patterns: Depending on the retaining wall size, a retaining wall can block on natural drainage patterns and have natural consequences downstream.
If your retaining wall is along with the property boundary, will the reinforcement system infringe the property line?
Overcharge Loads: Will there be extra weight or vertical forces above the wall such as fencing, guardrails, driveways, parking areas, or swimming pools? Remember about temporary construction equipment.
Soil:
The soil that creates the foundation, or base, should be analyzed to ensure it meets the strength needed to support the retaining wall. You should determine the characteristic, bearing capacity (the capacity of soil to support a load), stress boundaries, and friction angle (resistance to movement) of the soil used for the establishment and reinforced zone along with the retained soil zone.
In general, the base soil should be firm, solid, and strong, and it should not be moist. Wet soils such as clay soil are also not suggested for infilling. They are as of now soaked with water, so additional moisture cannot make its way through to the drainage channels. Likewise, in regions where there is freezing, Also, in areas where there is freezing, wet soil can expand and contract which will damage the retaining wall structure. Counsel the geotechnical report which describes the on-site soils, expansive soils, poor compound properties, groundwater conditions, and more.
Drainage:
Considering that water is the main reason for the retaining walls to fail, So it’s important to make sure your wall structure has good drainage system and that there will be no build-up of water bodies behind the retaining wall structure. Recognize potential surface water sources and make sure to drainage adjacent to the retaining wall site has been represented. It is essential to grade the site for drainage patterns and construct a drainage system behind the retaining wall structure to minimize the measure of hydrostatic pressure the groundwater could make. An example drainage system could include refilling with rock, using channel lines, and using “weep” openings to allow water to pass through the wall. Larger wall construction projects, such as those for transportation, should have a hydrology analysis done.
Design:
To begin the design, you should compute the corresponding retaining wall heights, footprint sizes, slopes, and the setback angle which are dependent on the site elevation and grade. You should also consider that gravity will cause the retained material to move naturally down a slope. This should be counteracted within the design to limit the amount of earth pressure behind the wall structures, which, at maximum value, can eventually overturn the wall. Your retaining wall structure height is dependent on soil and slope, setback, and size of the block.
Have a look at some of the concrete retaining walls we’ve done.