MAKING CFA DRILLED PILES WITH A CONTINUOUS SPIRAL WITH A DIAMETER FROM 400 TO 1000m
LHR performs these piles with a diameter of 400 to 1000 mm and a length of up to 24 m.
These piles have the same purpose and load capacity as the classic drilled piles. They are performed faster and easier. The technology of making piles consists of drilling the soil with an endless spiral with a diameter of 400 to 1000 mm to the projected depth. Then, the concrete pump outlet is mounted on top of the endless spiral and concrete is installed in a controlled manner through the central opening of the endless spiral from the bottom of the shaft to higher, with the endless spiral gradually being pulled out of the shaft. After the concreting is finished, with the help of a vibrator, the previously prepared reinforcement cage is installed in the fresh concrete.
Continuous Flight Auger piles, known as CFA piles, are increasingly used because their construction is very economical. With proper design and planning, efficient equipment and an experienced workforce, exceptional effects can be achieved. The advantage of these piles, in addition to economy, is the production with slight vibrations and noise. Also, if problems arise during the construction of the piles, it is relatively easy to re-drill and place the pile in the same spot, which eliminates the need to redesign the groups of piles and pile caps.
The construction of a parking space under future buildings opens up several interesting engineering problems, one of which is the most important protection of foundation pits that can go several floors in depth. Anyone who has dealt with this issue in theory and practice knows what problems the occurrence of groundwater causes in the construction of such structures, it is usually not recommended to lower the groundwater level in all terrains and when the surrounding facilities are close, and especially not when open excavation is planned to last a long time. In these cases CFA piles can be very efficiency solution