Our Patented DDP: Original, Field-Proven
DeWaal pile diameters range from 12 to 24 inches and pile lengths routinely exceed 100 feet to a maximum of 165 feet. Ultimate geotechnical pile capacities commonly exceed 500 tons. DeWaal piles are installed by Morris-Shea’s fleet of powerful drill rigs. These state-of-the-art drilling platforms are equipped with clean diesel engines and advanced sound suppression technology that limits their noise level to as low as 70 decibels at 100 feet.
Prior to installing each pile, the pile ID is entered into Morris-Shea’s Automated Monitoring Equipment. Two drill tenders then use a special device to safely hold and secure a detachable endplate onto the DeWaal tool as it is slowly lowered to the ground. This endplate serves as a cutting edge and prevents soil or water from entering the tool during drilling.
No Vibrations or Drilling Spoils
The DeWaal pile is advanced into the ground using high rotational and crowd forces. As this innovative tool penetrates the soil, the partial displacement auger transports soil to the full displacement element. This action thrusts 100% of the cuttings laterally against the sidewalls of the borehole, causing densification of the soil profile. A centralizer at the bottom of the drill mast maintains horizontal control of the tooling. The heavy wall drill stem serves as a temporary casing that follows the DeWaal tool and stabilizes the borehole. This unique drilling process produces no vibrations and virtually no drilling spoils.
The sacrificial endplate is left behind in direct contact with the soil. The reverse flight located on the topside of the displacement element assists with the extraction by cutting and re-compacting any loose soils. This added soil densification helps to minimize concrete over consumption.
Upon attaining the specified depth in the bearing layer, advancement of the DeWaal tool is stopped. A drill tender uses an OSHA- approved personnel elevator to ride up the side of the drill mast to a level slightly above the rotary. A full-length center reinforcing bar is hoisted to this level by an auxiliary winch and guided by the tender into the 10 inch diameter drill stem. It ultimately reaches a specially-designed conical shaped recess in the center of the sacrificial endplate.
High Quality Piles Formed Every Time
Prior to lifting the tool, the drill stem is filled with a self-consolidating, high slump, coarse aggregate concrete. It functions as a tremie pipe from which pressurized concrete flows while the DeWaal tooling is withdrawn. The sacrificial endplate is left behind in direct contact with the soil. The reverse flight located on the topside of the displacement element assists with the extraction by cutting and recompacting any loose soils. This added soil densification helps to minimize concrete overconsumption. The reliable and easily repeatable DeWaal method of concrete placement ensures high quality piles are formed every time without risk of cross sectional reductions, which are a commonly associated with augercast piles.
All aspects of the drilling process and concrete placement are observed and recorded by the Morris-Shea Automated Monitoring Equipment. Upon completion of each pile, the rig automatically transmits installation data to our team of project managers and quality control professionals. The drill tenders finish by placing a prefabricated reinforcing steel cage manufactured by the Morris- Shea team into the concrete.
DeWaal DDP Installation
The DeWaal Pile System is a drilled, full displacement, cast-in-place concrete pile installed by powerful, fixed mast drill rigs capable of applying high rotational torque and crowd forces to the unique DeWaal tool. Installation of this patented system is performed in a safe, simple and rapid single-pass process that densifies the soil, improves shaft friction and increases overall pile capacity. The DeWaal pile is ideal for installation in loose to medium-dense soil profiles including those with shallow groundwater tables and seismic design requirements.
Safer, Faster, More Economical
DeWaal DDP can be installed as a one-to-one, equal capacity replacement for driven and augercast piles with no foundation redesign. DeWaal piles are safer, faster and more economical than driven piles. This field-proven pile eliminates pile driving concerns such as hammer noise and vibration, material lead times, large staging areas and excessive material waste. Unlike augercast piles, the DeWaal system provides higher load bearing capacity, improved quality control and the elimination of drilling spoils. DeWaal piles can be installed in close proximity to sensitive operating equipment or in urban areas with noise and vibration restrictions. DeWaal piles also eliminate the expense of hazardous waste removal from projects with contaminated soils.
A More Effective Pile
Since 1992, Morris-Shea has installed hundreds of thousands of DeWaal piles throughout the United States, the Caribbean and South America. Today, the DeWaal Pile System is providing foundation support for all types of structures including highrise buildings, hospitals, water treatment, manufacturing, industrial and petrochemical facilities. Many of these projects were initially designed with other types of piles before it was determined that DeWaal piles were a more effective solution.