| 摘要 |
A bollard type trafficway barrier for arresting vehicles, comprised of a cast in place foundation and a mounting frame replaceable therein to carry a lift means for the bollard that is directionally oriented with respect to traffic so as to withstand great impacts, and with access for replacement of the bollard, extension and retraction being instantaneous by impact resistant fluid power and controls, the installation being flush with the grade when retracted and the bollard being remotely controlled for above grade extension and retraction.
|
