The design and construction of drilled foundations in the recent years has become widely popular, owing to the developments in drilling techniques related to equipment, materials, and overall improved methodologies in construction. Furthermore, all the advancements in technology for testing has resulted in high improvements in performance, design, and reliability.
Cased Drilled Shafts are necessary when ground conditions are so unsound that drilled holes cannot safely be maintained with drilling slurry, or, where loss of ground must be managed. Casing can be temporary or permanent steel pipe that offers a 100% even excavation for the entire length of the drilled shaft. Casings may be installed by either vibro hammers (when vibrations and noise are of no concern environmentally or to surrounding structures), or by high capacity impact. Otherwise, the use of oscillators and/or high torque drill rigs is the only remaining option.
Cased Drilled Shafts are the only established technique to drill large diameter shafts in caving conditions, such as gravelly soils with cobbles and boulders and loose sands. Boulders numerous feet in diameter can be safely removed by using specialty grab tools which cause no major interruptions to the excavation method. Environmental concerns are minimized or completely eliminated by this process since only water is used for drilling. The Oscillator method provides a more advanced technique for drilled shaft construction with ensuring an uninterrupted construction timeline through the elimination of anomalies.
Cased Drilled Shafts integrates Oscillators and/or high torque drill rigs to advance heavy wall steel casing into the ground simultaneously with the excavation without any vibrations or ground loss. Permanent steel casings or sectional temporary (detachable) casings can be installed over a certain depth, or the full length of the drilled shaft. Temporary drill casings are installed in sections of usually 1000mm to 5000mm and attached with a double wall bolted connector, giving a level outside diameter of the casing. Carbon teeth on the casing tip permit for greater installation depth and allow the advancement through obstructions as well as insertion into rock.
Uncased Drilled Shafts are one choice when the soil is secure enough to support itself or caving of the borehole can be avoided with the use of a water head or drilling slurry (Polymer or Bentonite). Shaft pile diameters most often range from 500mm to roughly 2400mm, with sizing of up 3600mm or more, which are only feasible in very stable ground conditions. Average shaft lengths vary from 3 meters if bearing layers are fairly shallow, to common depths of 18 to 20 meters. Depths of upwards of 77 meters are only achievable with specialized drilling equipment.
Red Deep Piling owns and operates some of the largest and most technologically advanced drilling systems in the country. Being a completely family-owned business we have earned a reputation through the years and today that no job is too big or too small for us. We can drill shafts that range between 400mm to 3 meters, and can install piles as deep as 77 meters. We have extensive experience in belled piles and rock sockets drilled cast in place piles. With us, you do not have to worry about any kind of difficulty because we know exactly what it takes to give you accurate measurements and the right advice for your design solutions.