CAISSON TYPE PILE METHOD MAKING USE OF PACKED CONCRETE

PROBLEM TO BE SOLVED: To provide a caisson type pile method making use of packed concrete capable of eliminating voids between earth retaining material and bedrock hole wall, eliminating a backing material and carrying out simple execution in sound work environment. SOLUTION: Water permeable ring shaped bags 20 are arranged along a hole wall of an excavated hole to cast concrete. Water is dewatered by casting pressure to form packed concretes 21. Repeating the constitution, the packed concretes 21 are piled up and down to use them as an earth retaining material. The bag is swelled in a state to project onto the outside of a ring, and it is tightly contacted to the hole wall and is dewatered to harden. By the constitution, in a caisson type pile method for a caisson type pile and shaft excavation, the collapse of a bedrock hole wall is prevented, the conventional execution of the backing material can be eliminated, and execution with safe and high economic efficiency can be carried out. Since water is only permeated, the sound work environment can be realized.