Roadway substructure frost-protective layer - of ballast of non-foamed plastic or rubber scraps hardened by high energy radiation

摘要

The frost protective layer is for incorporation in the substructure of roads, and other traffic-bearing routes, where serious damage can result from the effects of thawing after freezing, usually preventable only at considerable expense. Here the protective layer is made up from a ballast of non-foamed plastic or rubber material, in pieces which are subjected to a hardening process by a preliminary intensive irradiation with energy-rich rays. This produces a pronounced reticulation effect, causing the material to harden, and only a comparatively thin layer is needed. No specially rigid bedding layers are needed above it, and very little earth excavation is involved. Old pieces of tyres, and similar rubber scrap, can be used. Heat insulating qualities are not reduced by prolonged water absoption.