| 摘要 |
PROBLEM TO BE SOLVED: To obtain a cement-base grout which has a gelation time easily adjustable, is excellent in penetrating proprieties, does not exhibit gel shrinkage and loss of silica by dissolution, by hence an retain solidification strengths and water-stopping properties for a long term by compounding colloidal silica with fine-particle cement having a specified particle size. SOLUTION: This ground comprises colloidal silica and fine-article cement from which almost all the ultrafine particles having particle sizes of about 2μm or lower have been removed and which has an average particle size of 10μm or lower. The addition of an alkali agent to the ground comprising colloidal silica and the fine-particle cement gives a mixture which hardly exhibits the increases in viscosity and has a gel time prolonged and hence further improved penetrating properties. Examples of the alkali agent are an alkali hydroxide, an alkali carbonate, and an alkali hydrogencarbonate, but an alkali metal hydrogencarbonate is sp. pref. |
