Rotary augers have been around for decades. There are many different types available and they can be used in a number of ways. For instance, you can use a continuous flight auger or a crawler type auger for pile driving. Read on to learn more about these types of augers and why they may be suitable for your pile driving project.
Large Diameter Auger
Large diameter rotary auger bored piles are commonly used as foundations for medium to large structures. These piles can carry extremely high loads. They can also be used for retaining walls and basement construction.
Pile foundation types vary depending on the ground conditions. For example, in soft soils, it is better to use the Continuous Flight Auger (CFA) piling technique. This technique is ideal for most residential and business projects. However, it is not adequate for very soft silts or clays.
CFA piles are constructed by injecting concrete into a hollow stem of an auger. After this, the stem is removed and the soil is collected in spaces between the auger flights. Once the required depth is reached, the auger is removed. Depending on the size of the hole, the auger can be as long as three meters.
The method of installation of rotary bored piles is quick and easy. They can be built to any depth, from a shallow cut-off level below the platform to a full-depth cage.
Continuous Flight Auger
Continuous flight auger piles or drilled displacement piles are a fast and efficient method for installing foundations. They can be constructed with any type of soil or rock and are suitable for most applications. They are also low in noise and vibration.
Unlike bored piles, continuous flight augering requires less pressure and produces less noise. This is because the auger is withdrawn only when it reaches the desired depth. The resulting hole is never left unsupported.
Continuous flight augering is the most common method of piling. It is an effective method of constructing concrete deep foundations without leaving an open hole. Depending on the type of construction, the type of soil or rock, and the load bearing strata, the pile foundations can range from 12 inches to 48 inches.
In comparison to continuous flight auger piles, rotary bored piles can be used in soft rock and non-water bearing clays. They can also be used to overcome underground obstructions.
Crawler type auger pile driver
The present invention relates to a pile driving device. It has a number of unique features. Some of the notable characteristics include a low settling speed, a resonant response, a small diameter, and the ability to convey the monkey impact.
A first embodiment is illustrated in the following figure. This embodiment is particularly suited to hollow piles. However, the exemplary features of this invention can be found in other embodiments as well.
In the case of the present invention, a sonic hammer is used to generate a resonant response in a pile. These hammers work in the 90 to 120 Hz range. The resonant response makes the pile easier to drive.
Another exemplary embodiment is based on a rotary auger bore and a cylinder. While the rotary auger is widely used to drive steel pipe piles into the ground, the cylinder is best suited to drive a hollow pile.
One embodiment includes a cylinder, a sonic hammer, and a piston. The cylinder is the most technologically advanced of all the parts. For example, the cylinder has two rams, or rams I6 and 16a. Among other things, these rams contract and expand.
When the Swedish company NCC Construction was given a contract to install a storm sewer in the Central Station in Gothenburg, Sweden, it was important to reduce the noise emitted by the rotary auger bore to meet local restrictions. The construction was located in a busy area and a time limit of 14 days placed efficiency at a premium. Riggtech, a Swedish manufacturer of drilling and boring equipment, was contacted.
Typical methods for reducing the noise emitted by an auger include the use of noise dampening material between the shaft and the mounting flange, isolation of the auger from the machine, and construction of the auger to reduce the vibrations caused by the outer shaft. Other variations are possible in exemplary embodiments.
In one method, a steel temporary casing is installed into the ground. This casing is either vibrated into place using specialist vibrator equipment or screwed into the ground using a rig. Once in place, the casing is sealed into clay to prevent ground water from entering the bore.