| 摘要 |
A method for breaking a hard compact material such as rock or concrete. The method includes drilling a hole into the material, gripping a portion of the wall of the hole by applying a radially outwardly directed force thereto, and applying an axially outwardly directed force to the gripped region in order to cause cracks to arise in the wall of the hole. One of the forces is generated by means of sequentially repeated axially directed impacts. The apparatus for carrying out the method comprises a gripping means and a wedge means slidable relative to the gripping means. The gripping means and the wedge means have cooperating wedge surfaces. A rear extension member having a shoulder is attached to the wedge means. A hammer piston reciprocable in the apparatus housing delivers sequentially repeated axially directed impacts upon the shoulder. |
