METHOD TO MANUFACTURE CAST-IN-PLACE PILES Russian patent published in 2012 - IPC E02D5/38 

FIELD: construction.

SUBSTANCE: method to manufacture cast-in-place piles consists in suspension of a casing pile to a pile driver, its resting against soil, filling the lower part of the casing pipe with a loose material and its compaction with a falling hammer of the pile driver to form a plug in the casing pipe, afterwards the casing pipe is submerged to the specified elevation by hitting the plug with the hammer, and then by dropping of the hammer from high altitude, the plug is knocked out with simultaneous formation of bottom broadening under the casing pipe, installation of a reinforcement frame and concreting of a pile shaft with simultaneous withdrawal of the casing pipe. After the casing pipe achieves the design elevation, the plug is pushed out with the help of higher strikes of the hammer until it starts moving, at the same time with every hit, while pushing the plug, the casing pipe is withdrawn to the height from 2 to 3 cm, and after pushing the plug to the depth equal to the half of the casing pipe diameter, withdrawal of the casing pipe is stopped, and it is again driven into soil with at least 20 hits of the hammer. The plug is pushed out leaving its safe remainder, at the same time the plug material forms an integral part of the pile foundation. The additional amount of loose material is added to the casing pipe, which is rammed using the hammer with simultaneous withdrawal of the casing pipe, thus forming a broader pile foot. Prior to installation of the reinforcement frame, the casing pipe is set into the finished pile foot, and the plug remainder is fully pushed out. The reinforcement frame is installed into the casing pipe with its forced deepening into strong bearing soil, and the entire pile body is concreted by means of continuous laying of cast concrete with simultaneous raising of the casing pipe.

EFFECT: higher rates of pile body concreting, increased bearing capacity of a cast-in-place pile due to reinforcement of weak soils, reduction of material intensity and labour intensiveness.

15 cl, 5 dwg