Retaining walls can be an integral part of keeping your Jamestown, RI, yard safe and usable. Especially with extreme weather events getting more common, retaining wall failures can be inconvenient, expensive, and even potentially dangerous. In this guide, we introduce you to common retaining wall failures and how having your retaining wall inspected by a certified mason who can address potential problems will help you avoid them.
Poor drainage is one of the foremost causes of retaining wall failures. Accumulation of water in the retained soil and backfill material can radically increase the forces acting upon the wall. This build-up of hydrostatic pressure can eventually cause a wall to crack and even collapse.
Naturally, the way to avoid such an outcome is to integrate the right drainage systems into the construction of the retaining wall, thereby allowing water to seep out. Weep holes are a common solution, consisting of perforated pipes leading water from the backfill material to the face of the wall. For more severe problems, underground drainage pipes and trenches may be required to help the soil drain more effectively. Addressing poor drainage is generally quite expensive after a wall has been constructed, which is why having an expert contractor well versed in the nuances of local climate and soil types is an invaluable asset during the construction and design phase.
A sturdy foundation is an important prerequisite for durable and safe retaining walls. This requires creating a base trench that is deep enough to support the weight of the wall as well as to withstand the pressure of the soil it’s retaining. The foundation has to be flat and properly compacted to provide a stable base for the weight of the wall to be evenly distributed. A weak foundation can cause a wall to sag and eventually collapse. Integrating a geotextile grid into the construction is also necessary as it can help spread the loading evenly across the soil while also providing traction for the coarse aggregate layer and preventing it from slipping.
Poor Construction, Materials, and Design
Correcting a wall that has been constructed with substandard materials and poor construction and design can be disastrous. Using the right wall stones from a reputable manufacturer and fortifying them with a rebar steel mesh is especially important for high load-bearing walls. The quality and correct application of the mortar is also important as it binds the wall stones together and provides structural rigidity.
Failing to correctly account for the weight of the soil during the design process is also a common cause of retaining wall failures. Ideally, the wall should be over-engineered with a deeper base and thicker wall stones to ensure that it can withstand pressures beyond its design, which can occur during heavy rain or because of gradient variations.
Placing excessive loads on the retained soil can spell disaster for the retaining wall as it experiences forces it wasn’t designed for. This can range from parking a car or constructing a shed on the retained soil. If such cases are unavoidable, the wall has to be first strengthened to accommodate the extra load.