Retaining walls serve to retain the lateral pressure of soil. More simply, retaining walls are used to hold back soil and substrate from moving due to the effects of gravity and erosion. Retaining walls are typically designed out of concrete, stone, wood (including railroad ties), vinyl, masonry, steel, or brick.
This article discusses how to identify retaining wall-related issues and how to repair them.
Identifying Retaining Wall Failure
Signs of a failing retaining wall are usually easy to identify, but it's important to know that these symptoms will become increasingly worse over time. Unless proper repairs are made, the wall will eventually fail completely.
Most often, a retaining wall will show signs of failure in one of three ways:
Collapsing/Tilting Retaining Walls
Soil issues and/or poor construction are often the culprits for retaining walls that are tilting. This can happen if the footing toe is too small or if the wall wasn't properly reinforced. Railroad tie retaining walls can begin to collapse due to wood rot or deterioration. Most retaining walls require drainage "weeps". If water accumulates behind the wall, this additional weight can cause clay soils to expand, leading to cracks and tilting.
Retaining Walls Separating from Adjacent Walls
Like collapsing/tilting retaining walls, walls that are separating from adjacent walls are often caused by poor quality construction. A separating retaining wall may not have been designed to withstand the weight that actually bears on the wall. Poor drainage and inadequate reinforcement or connection to the adjacent wall are other possible causes. In unusual cases, expansive soils may also cause a retaining wall to separate from an adjoining wall.
Crumbling/Failing Retaining Walls
Retaining walls can crumble for a wide variety of reasons, most related to improper design of the walls itself. Often, the wall was not designed to bear the weight load behind it. In the case of concrete retaining walls, the issue may be inadequate, weak, or poorly mixed concrete. Concrete retaining walls may also have been designed with inadequate steel rebar, resulting in insufficient strength.
How to Repair Retaining Walls
To repair retaining walls, Thrasher typically recommends either wall anchors or helical tiebacks to restore structural integrity. Both wall repair techniques use a strong steel wall bracket on the exterior of the retaining wall to brace the wall and properly distribute the anchor's clamping pressure.
With both wall anchors and helical tiebacks, we will also attempt to return the wall to its original position, restoring its appearance and structural integrity.
Wall anchors accomplish this by driving an anchor rod through 1" holes driven into the retaining wall. These rods are connected to earth anchors that are placed within augured holes within the soil beyond the retaining wall. Once assembled, the wall plate is installed, and the rod assembly is tightened. This can potentially straighten the wall and return it to its original position.
Helical anchors are installed from the exposed face of the retaining wall, through a hole cut in the wall. The anchor's helical blades help to pull it deep into the soil and anchor it there. After closing the hole in the retaining wall, a wall plate is installed and a nut is tightened over the protruding threaded rod to brace the wall.
Wall anchors are generally the more economical solution to repairing a retaining wall. However, in some cases, wall anchor installation is not a possibility, and helical anchor installation must be considered. This includes situations where rocky soil is an issue, or when space restrictions make auguring a hole beyond the retaining wall an impractical solution. Our foundation repair specialists will be able to advise you on the most appropriate solution for you.
Contact the Retaining Wall Repair Experts
If your retaining wall is tilting, separated from adjoining walls, buckling, cracked, or crumbling, Thrasher can provide you with an expert repair solution. Our experts can identify the cause of the problem and restore your wall to its original condition. We provide warrantied solutions for retaining wall repair throughout Nebraska, Iowa, and Missouri. For homeowners interested in learning more about their unique problem, we offer free retaining wall repair inspections at no obligation.
Contact us today to get a free inspection for retaining wall repair.