Bored Pile
Another type of reinforced concrete pile which is used to support high building which has a heavy vertical load. A bored pile is a cast-in-place concrete pile where the bored piles have to be cast in the construction site while other concrete piles are pre-cast concrete pile cast in the factory. The machine used for this pile method is a bored piling machine which has specially designed drilling tools, bucket, and grabs, which can drill into 50 meters depth of soil.
Bored piling is best for tall buildings or massive industrial complexes, which requires foundations which can bear the load of thousands of tons. Bored pile drilling method has little vibration and a lower noise level.
Continuous Flight Auger Pile (CFA)
CFA Piles are formed by drilling a continuous flight auger into the ground. The sides of the hole are supported at all times by the soil-filled auger, eliminating the need for temporary casing or bentonite slurry. Upon reaching the required depth, sand element grout or concrete is pumped down the hollow stem as the auger is steadily withdrawn. Reinforcement is placed immediately after withdrawal of the auger.
There are numerous benefits to this approach, including immediate replacement, zero subsidence, lack of free water within the shaft, computer monitoring of depth and concrete placement and no need for casing/slurry.
Micropile
Micro piles are also called mini piles. Micro piles are normally made of steel with diameters of 60 to 200mm. A typical micro pile construction involves drilling the pile shaft to the required depth, placing the steel reinforcement, initial grouting by tremie and placing additional grout under pressure where applicable.
The advantages of micropile are high carrying capacity, less site constraint problems, and self-sustained operation. This piling system is therefore attractive to both the client and the foundation designer. Apart from the light compact drilling rigs, other auxiliary equipment, like grout mixer and grout pump is very compact in size. Where the demands of the job require piles in low headroom or otherwise restricted areas and for specialty or smaller scale projects, micro piles can be ideal.