PILE HOLE DRILLING METHOD AND FOUNDATION PILE CONSTRUCTING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a pile hole drilling method and a foundation pile constructing method which use a proper amount of a drilling liquid, cement milk, etc., under automatic control in correspondence to the strength of the nature of soil to enable efficient pile hole drilling and construction of a rational foundation pile structure fit to the nature of soil, and reduce an amount of muddy water discharge and of earth discharge.;SOLUTION: (a, b) As a drilling head 2 of a drilling rod 1 drills a pile hole 6, smearing drums 5 and 5a smear excavated soil on the hole wall. In drilling one pile hole, a formation that is not expected to have bearing power is drilled without using the drilling liquid, such as water, and a formation that is expected to have bearing power is drilled using the drilling liquid, such as water, as a drilling assisting means. (c) An integrated current value during the drilling is measured to automatically control the use/nonuse of the drilling liquid and the amount of use of the drilling liquid in correspondence to the strength of the nature of excavated soil. The amount and position of delivery of cement milk into an enlarged base 16 are also automatically controlled so as to form proper soil cement 11 by stirring and mixing the soil and cement milk together.;COPYRIGHT: (C)2008,JPO&INPIT