| 摘要 |
PROBLEM TO BE SOLVED: To further reduce noises to suppress noise pollution by vehicles due to reduction of generation of noises based on expansion of the compressed air sealed within the tread pattern of the tire because air is hardly sealed and compressed within a tread pattern of a tire in case of traveling of a vehicle on the surface of a manhole lid as the result of narrowing the top end surface of a motif section. SOLUTION: In the lid for underground structure having the motif section provided on the surface of a lid body in a protruding manner, the motif section is formed by intermittent motif section constituting members while maintaining the continuity of the motifs, and one constituting unit of the motif section constituting members has a width of 5-25 mm and a length of 30-150 mm. COPYRIGHT: (C)2011,JPO&INPIT
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