Drilled shaft is also known as a drilled pier, is a deep foundation element used to support structures by transferring loads to deeper, more competent soil or rock layers. It is a type of foundation construction that involves drilling deep vertical holes into the ground and filling them with reinforced concrete. These holes are filled with concrete or reinforced with steel to form piles, which provide structural support for buildings, bridges, and other structures.
Several specialized tools and equipment are used in the construction of drilled shafts. Here are some commonly used tools:
drilling rig: A drilling rig is a large machine specifically designed for drilling deep holes in the ground. It provides the necessary power, torque, and stability to perform the drilling operation.
Augers: Augers are drill bits with helical flights that are used to remove soil or rock cuttings from the drilled hole. They come in various sizes and designs depending on the specific drilling requirements.
casing: Casing is a steel pipe used to stabilize the drilled hole during the drilling process. It helps prevent soil collapse and maintains the integrity of the hole.
tremie pipe: A tremie pipe is a long, flexible tube used to pour concrete into the drilled shaft. It is inserted into the hole from the bottom, and the concrete is poured through it to ensure a continuous and controlled flow.
Reinforcement Materials: Steel reinforcement bars, commonly known as rebar, are used to provide structural strength to the drilled shaft. The rebar is placed inside the hole according to the design specifications and provides reinforcement to the concrete.
Concrete Pump: A concrete pump is often used to transport the high-strength concrete from the mixing plant to the drilled shaft. It ensures a consistent flow of concrete and helps in filling the entire shaft with concrete.
It's important to note that the specific tools used can vary depending on the size and complexity of the project, soil or rock conditions, and the drilling method employed. The selection of appropriate tools is crucial to ensure the efficient and safe construction of drilled shafts.