Brief Description of a Helical Pier and its Uses
Known as helical piers are deep foundation underpinning elements that are constructed with the use of steel shafts with helical flights. By twisting the shafts into the soil with advanced bearing depth, the torque is also monitored to reach a pile capacity.
It is recorded that the helical pier technology is more than 100 years old. For construction and repair or renovation works, this system is considered to be a proven system. For foundation repairs where soil condition would need installation to be deep piles, this system is proven to be very effective solution. Especially if the work requires on existing buildings, helical piers would have competitive advantages over other systems.
Helical piers foundations need equipment that are just smaller, lighter and less specialized unlike the equipment used in other kinds of deep foundations. 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.
It is advisable for the contractor to be monitoring the torque it is required when installing each helical pier. The capacity of each pier is directly related to the torque rating, therefore the contractor will know at the end of each installation the load or capacity that a pier can support.
Note that helical piers can be immediately loaded after installation, meaning there is no curing time after installation. Minimal excavation will suffice in a helical pile because it is turned or screwed in. Since there are no spoils that are to be hauled away from the site, you save on the costs of removal and disposal.
There is not violent hammering or banging to install helical piers and this is a big advantage with regards to the reduction of noise.
Those existing foundations that are failing, can be solved using helical piers, and this is another very important advantage of helical piers, aside from being used in new constructions. Instead of removing the present foundation that failed and dispose it in a landfill, the helical piers are used over the present foundation, thereby creating a deep foundation system plus contributes to a 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.