摘要 |
<p>Voids in at least a part of an artificial or natural structure overlying a highly porous layer(e.g. a concrete road or airfield runway) adjacent an exposed surface of the structure are filled with a hardenable material by forming mutually spaced extractor and injector holes through said part and into said underlying highly porous layer; closely fitting a flexible fluid-impermeable covering over the exposed surface, the covering having adjacent its boundary edges an endless hollow wall that surrounds and opens towards the covered surface, and sealing boundary edges of the covering to the structure to form a substantially fluid-tight enclosure incorporating the hollow wall; evacuating air from the hollow wall and from each extractor hole and introducing hardenable material in a liquid or semi-liquid state into each injector hole; terminating evacuation of air from each extractor hole as hardenable material appears at the outlet of the hole and introducing hardenable material into the hole; and, when hardenable material is being introduced into all injector and extractor holes, gradually bringing evacuation of air to a stop as the hardenable material in the voids sets.</p> |