Cased augered/secant piles
Technologies
CAP/CSP (Cased augered/secant piles) technology was conceived for lined piles with the continuous flight auger method. A particularly efficient method of building secant piles for the formation of continuous structural and/or sealed bulkheads.
In the operating phases piles are dug with simultaneous driving of the casing and the augers into the soil. When casing is completely driven the pile’s digging may continue only with the blades. Once the digging phase is finished, the blades and lining are extracted; at the same time the concrete is poured through the internal passage in the core of the blades. Once pouring is done, the cage is inserted into the still wet concrete. The continuous diaphragm is constructed with secant primary and secondary piles, properly overlapped; with this application it is necessary to construct guiding walls to ensure correct planimetric positioning of the piles and to guide the lining pipe on the surface. The great performance of the rig is guaranteed thanks to the double independent rotary head that, assisted by crowd-force of the crowd-winch system, assures the best production rate.
Advantages
• The cased augered/secant piles method can be utilised in a wide range of cohesive and cohesionless soils, with or without the presence of a water-bearing stratum and without bentonite fluid as wall support. The use of a casing allows to overpass concrete existing structures and penetrate rocks.
• The technology does not produce shocks, vibrations, noise, allowing to work in urban areas.
• Cased augered/secant piles does not induce disturbances to adjacent structures and it prevents soil decompression.
• The cased piles grants verticality in the range of 0,5%.
• The minimum required equipment (the rig plus the concrete pump) allows to minimise the job site installation plant and to operate in very restricted areas.
• High industrial production rates can be easily reached.
Technical data
• Pile diameter: 800 to 1200 mm
• Pile depth: 22,5 to 28 m
• Cased depth: 16 to 21 m
