| 摘要 |
An apparatus includes running surfaces made from metallic I-beams one of the flanges of which is adapted to support tires, whereas the web is adapted to receive flat strips which are substantially perpendicular to the web. At least one of the flanges is adapted to receive stiffening flat strips which are substantially parallel to the web. Troughs made from a metallic U-section channel are adapted to be fixed at least partly to one of the flat strips and flanges and open toward the flange adapted to support the tires. Such flanges, web, flat strips and channel are united to constitute a formwork into which is poured concrete whose level is flush with the level of the flanges.
|
