What are the Uses of Helical Piers?
Deep foundation of underpinning elements that are constructed using steel shafts with helical flights are known as helical piers. In performing the construction, shafts are moved to a bearing depth by twisting them into the soil, and at the same time the torque is monitored to the pile capacity.
The technology of helical pier is over 100 years old. Considered to be proven for new constructions and repairs or renovation works, this system is well used. For foundation repairs where soil condition would need installation to be deep piles, this system is proven to be very effective solution. Helical piers as compared to other systems will prove to be more advantageous especially if the work involves existing buildings.
Unlike deep foundations that require more specialized equipment, in the helical piers, the equipment used are usually smaller, lighter and less specialized. With these conditions, the cost of mobilization or the move in and move out, is generally lower compared to the other systems. These conditions allow contractors then to go in tight or confined areas in helical piles installation as compared to the larger equipment which cannot fit into the area.
Helical piers are turned in with a torque motor like a wood screw being turned into a piece of wood, and this makes helical piles vibration free when installed that gives it an advantage. Remember that it is not advisable to work on additional structure on neighboring properties with already existing structures.
The torque should be regularly monitored when contractors are installing helicals in each pier. The contractor usually would know at the end of the installation the load or capacity of each pier since the capacity of each pier is directly related to the torque rating.
After installation, there is no curing time in the case of helical piers installation. Also, there is minimal excavation required for helical piers that are turned on or screwed in. Costs of removal and disposal are saved when installing the piers because there are not spoils to be hauled or removed from the area of construction.
Noise pollution is drastically lowered when helical piers are installed because of the use of smaller installation equipment that do not require violent hammering or banging.
There is another very important advantage of using helical piers and that is they are great solution to projects with existing foundation that failed, on top of being used for new construction projects. Contractors also use the helical piers under the existing foundation, rather than remove and disposal it in a landfill, and when this is done, there is a deep foundation system that is created contributing to the green environment.
Several factors would affect your project, and so it is wise to ask the help of structural engineer to see which method would be best for your project.
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