Process for supporting unlined trial bores comprises inserting flexible tubing in the bore hole and using a medium to place the tubing under pressure so that the bore hole is supported by controlled radial pressure

摘要

Process for supporting unlined trial bores comprises inserting flexible tubing (support tubing) in the bore hole and using a medium (gas, water) to place the tubing under pressure so that the bore hole is supported by controlled radial pressure and is prevented from falling in. Preferred Features: The pressure medium is let out of the tubing using a measuring device to reduce the bore hole volume so that the ground settles uniformly in the desired form. During preparation of the bore hole the radially expandable supporting tube is inserted with a lower medium pressure than the higher final pressure and therefore has a smaller diameter than the final diameter which in the final position completely fills and supports the bore hole.