Cracks and settlements are facts of life when it comes to concrete foundation construction. There have been many methods of repairing structures once they have settled, including helical piles, thrust piles, and micropiles. Each have their own uniqueness and applications where they should or should not be used. Helical piles are a simple and cost effective solution for light structural repairs. Push pillars are excellent for lifting heavy structures cost effectively. Now, micropiles are gaining popularity to reduce the effects of settlement in new and existing structures.
There are many names for micropiles: minipiles, pins, and roots are the most common. These piles are small diameter, grout-reinforced, rotary-drilled piles that can be installed to depths of 200 feet and through very dense layers of soil and rock. Unlike helical piles or thrust piles, micropiles are not affected by cobblestones and debris on the ground. Their sacrificial bit is designed to drill through these hard soils and embed themselves into the load-bearing rock layers, while maintaining a column of grout around a structural steel member in the center of the column.
Like helical piles and thrust piles, micropiles can be installed in areas of limited access with relatively small equipment. This maneuverability makes them ideal for foundation repair applications. Portable kits have been developed to allow access to foundations and other low-rise applications where soils or access limit other more conventional methods of foundation repair.
The Micropiles installation process begins with drilling into bedrock using a specialized drilling rig. Soil cuttings are blown out with air, water, or slurry, followed by column slurry created by the sacrificial carbide bit and threaded rod. The tips of the Micropiles are cut in elevation and a sleeve is inserted to fit the bracing bracket system. Load tests can easily be performed on production piles or test piles near the proposed locations.
Micropiles and their inherent advantages have gained popularity and acceptance by contractors and engineers in recent years. With advances in drilling rigs and shoring supports, micropiles are sure to become more popular in the foundation repair industry. For more information on foundation repair, visit a site like http://www.earthcontactproducts.com.
