| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a crime-prevention door with a high crime preventability, which can resist the turning of a thumb turn. <P>SOLUTION: This crime prevention door is equipped with a door board which is composed of almost flat plate-shaped metal plates 1A and 1B, and a door locking mechanism 3 for locking the opening/closing of the door board when the door board is mounted on a door frame 7. Concrete boards 2A and 2B with a thickness of 20 mm or less, which are composed of a ultrahigh-strength and high-toughness concrete-based raw material, are fixed to inner surfaces of the metal plates 1A and 1B at least in the peripheral part of the mechanism 3, and a honeycomb structure 6 is provided between the concrete boards 2A and 2B. The concrete boards 2A and 2B are mounted on the surfaces of the metal plates 1A and 1B via a rubber-based adhesive as an adhesive 5. Inside the door frame 7, a concrete block, which is composed of the ultrahigh-strength and high-toughness concrete-based raw material, is inserted at least into the peripheral part of the mechanism 3 on the side of the door frame. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
