| 摘要 |
<p>PURPOSE: To recognize existence of a buried structure safely without taking much labor or time by coloring with pigment, all or a part of backfilled earth(s) which is (are) used when various kinds of buried structure buried or built under an earth surface are backfilled. CONSTITUTION: Backfilled earth is formed as a treatment earth which is formed by mixing water and hardening-agent with sediment and/or the improved earth thereof, it includes foaming agent or foaming agent, and it is a colored earth having a color difference of 3.0 or more or 6.0 or more compared with present positioned earth. Pigment is not limited in either case of an inorganic system and an organic system, but an inorganic pigment is used as the pigment. The inorganic pigment has good alkali resistance, light resistance, weather resistance, and heat resistance. There is no browning of hue in the inorganic pigment. The color of the inorganic pigment is preferably to be an auxiliary color or a near color comparing with the present positioned earth. Colored earths 15 for recognizing buried structure are arranged on all upper surface parts positioned around a gas pipe 1 as the buried structure, upper surface parts, and both side surface parts, a roadbed 7 and a subgrade 9 are arranged thereon, and then road pavement 11 is carried out thereon. It is thus possible to obtain colored earth for recognizing the buried structure easily, recognize the buried structure by a constructor easily, and also carry out work safely.</p> |
