PROCESS FOR THE PROVISION OF INDUCTION LOOPS ON RAILWAY TRACK SURFACES, HEAT OR HUMIDITY DETECTING LAYERS AND CONTROL TRACKS FOR UNMANNED VEHICLES

摘要

PCT No. PCT/DE86/00436 Sec. 371 Date Jun. 20, 1988 Sec. 102(e) Date Jun. 20, 1988 PCT Filed Oct. 31, 1986 PCT Pub. No. WO88/03303 PCT Pub. Date May 5, 1988.In order to determine traffic density it is known to embed copper wires as induction loops in grooves. The copper wires, which are protected by means of corresponding sheathings, are then covered with a silica sand layer and usually secured against floating by wood wedges. The grooves, which are cut into the road surface, are grouted with hot asphalt. Moreover, it is known to place copper layers on the road surfaces and to seal them with plastics material. But difficulties arise, particularly in the area of joints, since the latter cannot easily be bridged. The invention first provides for the arrangement of a carrier layer (13) on the road surface (11), the subsequent spraying on of the conductor layer (15), and then the sealing of the conductor layer (15) with a protective covering (14) consisting of a plastics material corresponding to the material of the carrier layer (13). If the conductor layer (15) is arranged directly on the road surface (11), connecting pieces, which can be easily sprayed over, are provided in the area of the joints, the connecting pieces being elastic within certain limits. The conductor layer (15) can also be used as a heating layer, as a guide track or as a moisture detection layer.