| 摘要 |
PURPOSE:To produce a maximum ground improving effect by means of the relatively less number of driving times, by a method wherein plural drain boards are connected continuously to a flexible expansion joint part located to a central part. CONSTITUTION:Plural drain boards 7, each being formed such that non-woven cloths made of nylon and the like are adhered to both surfaces of a base body 9 made of polypropylene having a number of groove lines 8 on both surfaces, are adhered at an adhesive part 11 to an expansion joint part M to form a polyhedral radial drain board D. This enables increasing in size for effective drainage, and enables improvement in pressure bonding adaptability. |
