| 摘要 |
PURPOSE:To provide the titled ground conditioner consisting of vitreous blast furnace slag in powder and medium-heat Portland cement, which maintains low initial strength, insures increase of strength over a long period of time and facilitates operation. CONSTITUTION:The ground conditioner to be mixed in the depths of ground consists of (A) 40-80wt% vitreous blast furnace slag in powder and (B) 20- 60wt% medium-heat Portland cement. Ordinary grade Portland cement and blast furnace slag having a high initial strength have so far been used as ground conditioner, but they tend to cause solidification of a mixture of the conditioner and soil in a short time, sometimes causing part of solidified soil to be moved by a rotor blade or making it impossible to perform mixing and recover rotor blades and revolving shafts en bloc, thus leading to the necessity of pouring of additional batches of the conditioner and full-time operation day and night. The use of the medium-heat Portland cement maintains initial strength at a low level and insures increase of strength over a long period of time, making the operation very easy. |
