| 摘要 |
<p>PORTABLE BRIDGE A portable bridge structure for carrying trucks and other large vehicles is described including two longitudinal bridge sections which are transported separately to the bridge site and are fastened together after installation by means of pivotable diaphragm members. The pivotable diaphragm members are pivotally attached to one bridge section and after pivoting into position, are bolted to bracing flanges on both sections to fixedly secure the sections together. Each bridge section includes at least one longitudinal support member and a plurality of cross members extending across the top of such support member to provide a support frame of a generally T-shaped cross section. The longitudinal support member may be either a hollow built-up beam member or it may be formed by two I-beams which are joined together by rigid interconnecting members. The portable bridge of the present invention is especially useful on logging roads, and can be releasably mounted for removal at the end of the logging operation.</p> |
