The most commonly used foundation repair method in Texas has received significant engineering design upgrades, announced Dawson Foundation Repair. Martin Dawson, owner, stated that these advancements are the result of years of experience and a years-long focus on improving a system that has a number of inherent limitations. His staff and several independent structural engineers were involved in this process and the result is a greatly enhanced foundation repair system that is comparable in cost to the earlier system it is derived from.
“For over 30 years we have known that some homeowners simply cannot afford our premium product, Bell Bottom Piers, which offer a permanent solution. Usually these homeowners have homes valued at $150,000 or less and they would frequently choose a cheaper and lower quality option, commonly known as Pushed Piles. And the problem with Pushed Piles is that they have a number of inherent disadvantages that frequently lead to failed foundation repairs within ten years or less. So we put our heads together to design a better system, with similar costs, to serve the more economical part of the market,” stated Mr. Dawson.
Mr. Dawson explained, “The independent structural engineers were key to our efforts. We had a number of ideas and they helped us narrow them down to three key improvements.” The first improvement, as described by Mr. Dawson, was connecting the concrete cylinders (piles) together with a design that is sufficiently strong so that the column of cylinders will act as a single unit, or monolithic. This is accomplished by a steel rod that runs through the center of each concrete cylinder to connect all concrete cylinders is a vertical column. This greatly reduces the chance of “skewing” which is the “angling-off” of the cylinders during installation. It is very important to keep the concrete cylinders in a vertical column or the column will be unable to support the necessary weight. “This a significant design improvement,” states Mr. Dawson, “because none of the foundation repair contractors, including us, can guarantee a vertical installation of the pushed concrete cylinders. There is simply no test to confirm that the column is vertical during or after installation. However, with this innovation we have significantly improved the odds that the column will be vertical and will be able to support the weight of the house or structure.”
The second improvement involves the cap, which is a rectangular block of concrete that rests atop the vertical column of concrete cylinders. The Dawson team has strengthened the cap with a steel cage inside the cap. Therefore the steel cage can support much higher loads or weight without fracturing.
The third improvement includes the pressure injection of a grout slurry around the perimeter of the cap. One advantage of this process is that the cap will have a larger footprint in the soil and limit or eliminate the amount of water seepage downward along the column of concrete cylinders. This is importsant enhancement because too much water around the column will reduce its weight bearing capacity. Water reduces the skin friction between the concrete and the soil. Another advantage of this grouting process is that with the greater footprint the system can handle more weight, by a factor of 4 to 8. “All of the foundation contractors know that the Factor of Safety for the older Pushed Pile systems is 1. That is, the older systems will never be able to handle any additional weight after installation. Now the homeowner doesn’t have to worry about moving file cabinets, adding a home gym, or parking cars in the garage because our enhanced design can easily handle these additional weight loads,” added Mr. Dawson.
“We provide other services to our customers that most foundation companies do not offer. We perform a soil test before each job to confirm the depth of the stable soil, which is key to the successful installation of support columns. And we fill all sizable voids under a slab foundation with a soil/concrete slurry in order to give the foundation the necessary support,” added Mr. Dawson.