Weep-holes have provided relief from water build-up since ancient times, helping to provide a drainage outlet for water from the retained earth. Relieving hydrostatic load helps prevent damage to the retaining structure, such as a retaining wall, culvert, dam, tunnel, or seawall, and it helps extend the life of the structure as long as it continues to work. The problem is that traditional weep-holes, and all other traditional drainage systems see immediate efficiency loss upon installation, will eventually fail, and are not maintainable. This is where Jet Filter’s maintainable weep-hole systems are changing the way engineers are approaching drainage design and the use of this traditional approach.
Like all traditional drainage systems, the problem with traditional weep-holes is they are an unreliable drainage solution. As a stand-alone system, the lack of stone or geotextile filter fabrics, they allow soil loss leading to voids & sinkholes. In the case where geotextile fabrics are installed, soil fines will eventually clog the holes, and cause hydrostatic pressure to form behind the wall and begin compromising the structure as a whole. The only way to relieve this pressure is to redrill the hole, which would compromise the geotextile mesh and/or provide an outlet for loss of fines. Either way, the unsustainable circle of drill, clog, redrill begins. The Jet Filter weep-hole system addresses this with its maintainable conical mesh design.
One of the first issues Jet Filters address is keeping the soil fines behind the wall. The conical weephole filter system ensures that only water passes through both meshes, keeping the soil where it belongs. It additionally promotes the formation of a filter cake/transition zone, a granular filter that is self-formed by the fines and soil that drains to the mesh, on the upper portion of each of the meshes in order to keep water flow moving through the surface area of the filter. As most geotechnical engineers know, the creation of a filter cake is the goal of a geotextile drainage application, as it helps provide an optimal path for water flow and retention of soil fines.
The second issue Jet Filters address is long-term hydrostatic relief through optimal performance and maintainability. While the promotion of an optimal flow & soil filter is excellent, the fact remains is at some point all drainage systems will fail if not maintained. Traditional drainage systems are buried behind the wall and are not accessible to be maintained. Jet Filters provide maintenance opportunities in two ways. The first is the ability to remove the geotextile filter fabric, clean it, and reinstall it. This quick 2-3 minute process will knock out any material that may be causing the filter to perform sub-optimally. The second is being able to replace the entire filter cartridge quickly by removing it and replacing it within minutes. The maintenance schedule is approximately every 2-5 years, which is based on the amount of water flow and the soil conditions behind the wall.
Drainage efficiency is another problem Jet Filter weep-hole systems solve. The Jet filter conical design provides a much larger geotextile surface area than traditional weep-holes. While this helps promote the optimal filter cake, it also ensures surface tension of the water is never an issue and more water can drain from the weep-hole itself. With optimal spacing, water pooling of almost any volume can be effectively drained without compromising the structure.
In less than 10 minutes, a Jet Filter can be installed into an existing or newly cored weep hole in any material such as concrete, steel, vinyl, and more. The Jet Filter is simply inserted into the weep hole, fastened into place, and it’s complete.
To learn more about how Jet Filter Maintainable Weep-Hole systems can improve your designs, contact us for a presentation today!