After the Hanshin-Awaji earthquake, reconstruction of highways, bridges, etc. are could be observed all over Japan. The Hanshin-Awaji earthquake occurred on January 17, 1995, in Japan. During the reconstruction, the following forty works are conducted, which constitute a social problem. Figure 1(a) shows a regular work that a regular anchor bolt is used after a long hole is bored between the reinforcing members. Figure 1(b) shows forty works. The left side shows the work that the short anchor bolt is used, while the right side shows the work that a reinforcing member is cut. In the former case, the pull-out resistance of the anchor bolt decreases, whereas in the latter case, the strength of the concrete decreases. Irrespective of whether an earthquake occurred, reconstruction is necessary in all countries across the world because of the deterioration in existing construction. The present paper introduces the technology that allows a person to drill without damaging a reinforcing member and to insert a special anchor bolt (Fig. 2) [1]. Further, guidelines for efficient boring are given on the base of experiments.
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