| 摘要 |
<p>Compsn. for road construction, esp. for the foundation carrying the top layer, consisting of a granular mineral material and a hydraulic such as cement or lime, is improved in that the mineral material consists partly or wholly of the waste gaugue from coal mining. Material suitable for application onto any ground is produced in an inexpensive manner from a cheap material. The cumbersome wastes from the coal mining. are utilized. The material can withstand heavy traffic without subsiding or cracking.</p> |
