METHOD FOR DRILLING BOTTOMED HOLE IN SURFACE LAYER PART OF CONCRETE, AND ANCHOR FITTING FOR USE IN OPERATION OF DRILLING BOTTOMED HOLE

PROBLEM TO BE SOLVED: To provide a method for drilling a bottomed hole in a surface layer part of concrete, without applying an impact force, equal to/greater than an impact force in anchor construction, to a concrete skeleton, by utilizing an anchor fitting, and to provide the anchor fitting for use in the operation of drilling the bottomed hole. SOLUTION: This method for drilling the bottomed hole comprises: a first step of forming an annular groove 12 in the concrete 11; a second step of forming a drilled hole 13, approximately equal in depth to the annular groove 12, in the central portion of the annular groove 12; and a third step of applying the anchor fitting 14 to the bottom of the drilled hole 13. The application of the anchor fitting makes a horizontal crack appear on the bottom of the annular groove 12, so that a concrete mass 18 inside the annular groove 12 can be removed for the formation of the cylindrical bottomed hole 19. When the sufficient crack is not caused only by the application of the anchor, the crack appears in the extraction of the applied anchor fitting. COPYRIGHT: (C)2009,JPO&INPIT