| 摘要 |
<p>Fluid fill material is pumped from a site which is located remote from a void 24. The material is foamed by mixing a particulate solid material 34 with a finished foam 36 in a mixer apparatus 38. The aerated material may also include cement 32 or another binder for applications requiring structural strength. The bubble structure which results from incorporating the foam 36 in the fill material 34 is much more fluid and pumpable, thereby allowing the use of much higher solid to water ratios than would otherwise be possible while still being able to pump the material over significant distance. This reduces the possibility of mud slides and the need for drainage in the void. A defoaming agent may be used after the fill material has flowed into the void.</p> |
