| 摘要 |
<p>A sand concrete mixt. for sewer repair consists of (by wt.)5-20% cement, 4-20% ground vitrified blast furnace slag, 5-20% ground crystalline blast furnace slag and 50-75% blast furnace slag sand. Pref. the mixt. comprises 13-17 (esp. 15)% cement, 5-7 (esp. 6)% ground vitrified blast furnace slag, 15-17 (esp. 16)% ground crystalline blast furnace slag and 60-64 (esp. 62)% blast furnace slag sand or 5% cement, 15-20% ground vitrified blast furnace slag, 15-20% ground crystalline blast furnace slag and 55-65% blast furnace slag sand. Also claimed is a process for sewer repair by forming a concrete contg. 85-95 wt.% of the above mixt. and 5-15 wt.% water, spraying the concrete on the sewer gallery walls and allowing to set.</p> |
