If you happen to notice that the retaining wall on your property has started to bulge, crack or slip, you need to take urgent action. Though it is unlikely, your wall may be about to come crashing down, this could lead to some unpleasant outcomes like landslides or the reappearance of drainage problems that the wall was built to overcome. It is likely that you can save your wall so prompt action may prevent further damage.
You probably expected your wall to stand for decades so what caused it to fail? Appropriate retaining wall engineering should have prevented this from happening.
The Reasons Retaining Walls Fail
There are three main reasons why retaining walls fail
- Poor drainage – mud is considerably heavier than dry soil. If the drainage system is poorly designed water will accumulate behind the wall. This will cause a buildup of water pressure against the rear of the wall. Appropriate drainage will ensure that the water is correctly channeled
- Inappropriate backfill – with the incorrect backfill, the weight behind the wall may increase as water collects. Clay may swell. Insufficient gravel in the backfill will prevent effective drainage and could lead to wall failure
- Design error – design errors shouldn’t happen if you hired a trained engineer to design your retaining wall. Engineers have formulas and tables that they use to ensure that the retaining wall is up to the task
Retaining Wall Engineering Corrections
Most times, it is possible to the save the retaining wall by taking quick action. Here are some of the remedies for failing walls
- Redirect surface drainage
- Make more or bigger weep holes
- Replace the backfill
- Use tie-backs – the wall can be strengthened by using tie-backs but it requires an analysis of the force of the retained soil
- Extend the footing
An effective retaining wall engineering design will ensure that you can avoid the problems of poor retaining wall design and construction. Alternatively, a structural engineer can help fix the problem for you.
Learn more about Xpress Engineering’s affordable Engineering Retaining Wall Designs or Request a Retaining Wall Design for your own project.