| 摘要 |
PROBLEM TO BE SOLVED: To provide a noise preventive precast concrete cover product for facilitating manufacture and construction. SOLUTION: When manufacturing a precast concrete cover, a conical recessed part (about 3 to 5 mm at a maximum) is arranged in the four corners of a partition steel plate of a multiple manufacturing method by a drill, and concrete in poured into here, and a conical projection part 1-1 is constructed. COPYRIGHT: (C)2007,JPO&INPIT
|
