Erosion protection of riprap exposed to flowing water
We deliver permanent solutions for erosion protection of ground areas where there is a danger of erosion from running water.
Landfills close to rivers or ocean currents can be vulnerable to erosion. Big ships with strong side thrusters can also cause problems under quays and around pillars. Culverts, jetties, bridges and riverbanks are other areas where heavy water erosion can occur. Our technology is a robust, flexible, steel reinforced concrete mattress. The mattress is designed for each use, and engineering and installation is provided by our company.
Quay protection
A quay is normally built to last a long time, maybe 100 years. The ground around the construction is sometimes a weak point, especially if it consists of gravel/riprap and it is in contact with flowing water. Even if the concrete construction in itself is in good conditions the slope under quay deck or the ground around the pillars must normally be repaired several times during the lifetime of the quay.
Typical symptoms of erosion are settings in the ground on the surface behind the quay, slides in the plastering wall and riprap slope under the quay deck, and sediments on the bottom at the end of the slope.
Strong currents from the ships side thrusters can wash out fine sand and gravel very quickly. If it is the same area exposed to these currents every time it will need special protection.
The Marecom solution
The method is to cover the critical area with a steel reinforced, flexible PVC-mattress, and fill it with concrete. This provides a durable and robust protection of the riprap for the whole lifetime of the quay construction.
Erosion damages
Example of erosion damages under the quay. The plastering layer and slope is washed out in the hit area of the ships thrusters. The bearing of the construction is undermined.
The foundation undermined
The quay foundation is “hanging in thin air” several places, and if the erosion continues the whole construction is in danger of collapse. All the finer gravel is washed out of the slope.
Erosion stopper
Steel reinforced concrete mattresses are installed, and give a permanent protection of the ground. Each mattress on the picture is about 7 x 21 meters, and weighs about 100 metric tons.