| 摘要 |
<p>A composition for making impermeable walls and other underground structures comprising water, a cement, a silica compound in a dispersed form, and an activating agent selected from the group consisting of an alkaline base and an alkaline salt of a weak acid which do not contain silica, the ratio by weight of lime to silica being less than 1 and preferably between approximately 0.3 to 0.5.</p> |
