| 摘要 |
<p>1,092,255. Retarding surfaces. PYRENE CO. Ltd. Feb.2, 1966 [Nov. 10, 1964; Sept.20, 1965; Nov.10, 1965], Nos. 45788/64; 40005/65 and 4228/66. Heading E1G. A bed of crushable rigid foam material extends alongside or at the end of a vehicle track to retard vehicles leaving the track. The foam material may be aerated concrete and the thickness may increase in the normal direction of vehicle travel. Additional retardation may be provided by undulations in the bed.</p> |
