Helical Anchors/Tie Backs

Ram Jack® helical screw anchors, also known as helical piles, are round tubular steel shafts to which helix plates are welded. The helix plates arc simply round plates of various sizes that have been pressed into the form of a flat screw thread. When the anchor is rotated in the ground, the helix plates generate an axial thrust, causing it to advance just like a wood screw into wood.

Ram Jack® Foundation Repair Systems manufactures two standard sizes of helical anchor shafts, 2-3/8" O.D. and 2-7/8" O.D. Additional sizes are available by special order. The standard shaft material consists of high strength carbon steel tubing. The shafts are manufactured in various lengths, with couplings on the ends to allow them to be strung together to penetrate deep into the ground where necessary to engage competent bearing stratum. Special care is taken to ensure the helix spiral has a uniform pitch angle to minimize disturbance of the soil during anchor installation.

Shaft sections are connected together with a user-friendly threaded connection that resists axial (tension and compression) and lateral (shear and overturning) loads. This patented connection allows rapid make-up in the field and produces a rigid joint with better flexural and torsional stiffness than competitive products, resulting in better buckling resistance under compressive loads.

Applications

Ram Jack® helical screw anchors are used to transfer loads from the soil near the surface to deeper, more suitable load-bearing strata. They may be used in tension as for tower guys and tieback retaining walls, in compression as for building foundations, or in shear/overturning as for lighting pole or self-supporting tower foundations. They may be installed plumb, as for supporting gravity loading, or at an inclination to anchor tower guy wires or retaining walls for deep excavations. They can be used to support light loads such as wing walls, interior floors, porch slabs and parking lot light poles as well as heavier ones such as tiebacks on basement or retaining walls, masonry buildings and roadway lighting poles.

Ram Jack® helical screw anchors may be used in new construction where the costs or risks associated with conventional concrete foundations dictate, or they can be utilized to stabilize or remediate existing structures whose foundations are in distress. In these latter applications, they are often used in conjunction with (prefabricated steel brackets) that facilitate connection of the helical screw anchors to the foundation.

Advantages

• Can be installed in any weather
• Installation requires no excavation
• Installation utilizes no impact forces and produces no vibration minimizes the risk of damage to adjacent structures from soil movement
• Ready for use immediately after installation
• Installation produces no spoils to be disposed of or remediated
• Installation equipment is small and lightweight allowing work in tight quarters and on soft surface conditions

Ram Jack® helical screw anchors are superior to many other brands because of their innovative coupling method. This coupling method produces joints with absolutely no free movement in any direction, unlike the telescoping couplings of other manufacturers, making Ram Jack® anchors much more resistant to buckling under compressive loading.

Installation

Ram Jack® helical screw anchors are installed by screwing them into the ground. As with wood screws, it is necessary to provide both twisting effort and axial thrust to the top of the anchor shaft. These forces must be maintained during the installation to ensure the anchor does not either cease to rotate or cease to advance at the proper rate of about one pitch length (3- 1/2") per revolution. Installation can be done with either hand-held or machine-mounted equipment.