蒸気圧破砕剤SPCによるコンクリート解体システムの開発

―コンクリート中の鉄筋掘削工程について―

抄録

In a series of experiments on a demolition system using a steam pressure cracking（SPC）agent were conducted. The results were obtained by drilling 11 mm diameter（D10 class）rebar in concrete using three types of rake angle bits at the tip of a small rock drill with a power of 2.24 kW （Compressed Air power）. The rebar could be pierced by the rock drill a time of 730～1020 seconds. Thus, it was confirmed that it is possible to process holes for SPC for concrete demolition with reinforcing bars. However, a drilling speed of rebar was about one-fi ftieth of concrete. Observing the steel chips, there are two types of drilling mechanisms. One is a drilling mechanism in which the rebar undergoes compressive deformation at the tip of the bit, and microscopic chips are discharged at the tip of the bit with each impact. The chips are not more than 1 mm wide. The second is to discharge macro chips of several millimeters in size, and the entire rebar is subjected to compressive deformation and because of multiple impacts from the end of the rebar, drilling proceeds in steps.