| 摘要 |
PROBLEM TO BE SOLVED: To provide magnetic concrete which can be subjected to simple nondestructive inspection for determining the presence of cracks in the concrete from its surface by a magnetic method and also has an electromagnetic-wave shielding effect. SOLUTION: The production process of this magnetic concrete comprises mixing a magnetic fluid or magnetic fine particles with concrete to produce a double-functional concrete provided with a magnetic function. Accordingly, the presence of cracks in the magnetic concrete can be determined by magnetizing the magnetic concrete with an exciting coil and measuring magnetic field distribution of the concrete with a detection coil,,; from the surface of the concrete. Further, by employing the magnetic concrete as a structural material for M civil engineering and building fields, for example, a building constructed with the magnetic concrete itself has an electromagnetic-wave shielding effect. Thus, the objective magnetic concrete in which the presence of cracks can be determined with good accuracy and which has an electromagnetic-wave shielding effect can be produced. |
