Method and device for placing an improvement material into a soft ground through a vast number of points

摘要

When an improving material used for ground improving construction is ejected into the ground, an improving material having a predetermined gel time is ejected through a vast number of points simultaneously or selectively from ejection ports provided in an improving material transport passages such that the positions of the ejection ports are offset, the improving material can be ejected through the vast number of points as designed. A stroke, start and stop of an advancing and retreating movement adjusting device can be adjusted through a screw 32 of the advancing and retreating movement adjusting device, a slide guide 39 as a supporting mechanism is fitted to a slide bar 41 so that even if a load deviated with respect to a piston rod 36 is applied, the piston can be advanced and retreated smoothly, and an automatic on-off valve 34 is interposed in the piston 33 so that the improving material can be intaken and discharged smoothly. Since the improving material can be charged from the ejection ports through a vast number of points, it is possible to form a ground improved area having the same properties without deviation, the construction can be carried out as designed, the construction efficiency and accuracy can be enhanced, the cost is increased, a resource can be saved, and the pollution can be prevented.