Permanently And Temporarily Cased CIDH
Morris-Shea installs Permanently and Temporarily Cased, Helical Cast-In-Drilled-Hole piles that are ideal for use in restricted access sites. Helical CIDH piles are installed using a safe, quiet and vibration-free drilling technique similar to a conventional helical pier, only larger in diameter and with higher load bearing capacity. A powerful and compact drill rig advances the helical steel casing into the ground by simultaneously applying 20 to 50 meter-tons of torque and 20-tons of crowd force.
Permanently Cased Helical CIDH piles rely on a steel casing to improve load capacities and add lateral support. Temporarily Cased Helical CIDH piles typically achieve higher frictional capacity and implement the use of reinforcing steel cages, rather than steel casing, for lateral support. For certain projects, the temporarily cased pile can be a more economical solution.
CIDH Installation Method
Casings are inserted through the bottom of the rotary with the assistance of an excavator. A tube clam on the rotary secures the casing. Overhead lifting is not required. The four outrigger supports provide superior stability. Our powerful and compact rigs can handle individual casings as long as 80 feet in a single piece or short enough for use in low overhead applications.
The Morris-Shea drilling platform can easily maneuver in tight environments where applications still require high-powered drilling and high capacity piles. Our compact foundation equipment is suitable for restricted access sites such as inside buildings. The leader length is adjustable to the optimum height for every site. Some of our drill rigs can pass through openings as restrictive as 10 by 11 feet and operate efficiently in an interior space with only 13 feet of vertical clearance.
Typical casing diameters range from 8 to 18 inches. Helical CIDH piles can be installed within height restrictions as low as 13 feet. Where long piles are required with limited headroom, short casing sections can be welded together to achieve nearly any required pile length.
High rotational torque and crowd force are used to install Helical CIDH piles to the required depth. During installation, the Helical CIDH pile displaces and densifies the soil around the pile. No drilling spoils are produced or transported to the ground surface, making the system ideal for projects with contaminated soil. Casings are filled with self-consolidating concrete and reinforcing steel as required. This combination of steel casing, reinforcing steel and concrete fill creates load bearing capacities equal or greater than driven piles.