Leaning site walls are a typical problem that, until now, have not had many cost effective solutions for replacement. In the past, the most often used remedy involved removal of the existing leaning portion and replacing it on top of the existing footing. Few have actually replaced the footing itself. The issue is that even with the replacement of the footing; the original soil that is causing the foundation problem is still under the new footing and will likely produce similar performance of the new wall.
For costs that are now competitive with replacement, we can offer a solution that brings superior results. Arizona Foundation Solutions of Tucson, with the help of Dr. Peter Fleming, has developed a proprietary technology that will stabilize and raise the retaining wall, rotating it back into it's original position.
Micro piles are essentially small diameter piles that have the ability to be installed in any type of ground. They can be installed quickly in practically any type of environment, particularly in restricted or hard to reach areas with low headroom, because of the adaptive drilling equipment. Micro piles do not rely on end-bearing capacity, with design loads as small as three tons and as high as 500 tons.
Micro piles include a drilling process, placing reinforcing steel, and grouting - which bonds to the soil. One of the latest developments is known as a system and method, which combines all of these steps in a single step installation. This new method uses hallow bars.
The pile integrates completely with the soil. It forms a foundation system of reinforced soil mass, in particular if placed in groups. The piles are drilled and grout-injected in one step, using the hallow bars as drill rods and grouting ducts with disposable special drill bits and rotary drilling methods.
The drill bits have jet openings, allowing for pressure grout penetration while drilling into the soil. With the aid of a flushing head, the drill cuttings are continuously flushed by the cement grout during drill advancement and grout injection through the hollow bars. This method has a clear advantage because while the drill hole is stabilized, the ground cannot relax or cave around the drill location, as the soil around this area is being penetrated by the grout and causing it to densify.
The basic idea is that this method produces a pile with a very high capacity, but can still operate in tight areas with limited overhead space. For example, this method of micro piles can operate inside buildings to underpin foundations and even upgrade existing foundations. If using helical or push piers and micro piles won't work because of space limitations, this new method proves to be very adaptable.
Contact Arizona Foundation Solutions of Tucson for any foundation repairs, big or small.