Seawalls typically fail prematurely due to a couple of common causes. One of the main causes of seawall failure is soil migration, which can destabilize the entire structure. Another cause is hydrostatic pressure buildup on the landward side, which often contributes to soil migration.
Soil Migration and Seawall Failure
Soil migration is the movement of soil from one location to another due to various factors such as waves, tides, and storms. This can cause erosion at the base of the seawall, undermining its stability. In addition, soil migration can lead to the formation of voids or empty spaces behind the seawall, which can cause further destabilization. Void formations can occur when soil is washed away from behind the seawall, creating a space between the seawall and the ground. These voids can undermine the integrity of the structure, increasing the risk of failure. Soils that are not sufficiently compact or stable are more prone to erosion and void formation.
Hydrostatic Pressure and Seawall Failure
Hydrostatic pressure is the pressure exerted by a fluid, such as water, on a structure. When there is a buildup of hydrostatic pressure on the landward side of a seawall, it can cause the structure to become unstable and potentially fail. This water buildup can be caused by a variety of factors, such as high tides, waves, and storms. The effects of hydrostatic pressure buildup on the landward side of a seawall can be significant. It can cause the seawall to tilt or lean, increasing the risk of failure. In addition, the added pressure can cause the seawall to crack or break, leading to further destabilization.
Preventing Seawall Failure
To prevent premature failure of a seawall due to soil migration and void formation or hydrostatic pressure buildup, it is important to have a professional evaluate the condition and stability of the structure. If necessary, the supporting soil and the structure can be stabilized, and a hydrostatic pressure release system can be installed to prevent undue pressure on the wall.