摘要 |
The device for staying the walls of an excavation comprises armour plates with large plane surfaces (2, 3) of which the edges of each side are guided and supported by guiding grooves (5, 5') arranged on the stays (1). The stays are arranged by pairs facing each other and held in that position by struts (10). To decrease the resistance to friction between the plates (2, 3) and the stays (1) there are provided rollers (8, 11, 16) having horizontal axis. Each side of the guiding grooves (5, 5') of the stays which is farther from the wall of the excavation is provided with an array of rollers (8, 11, 16) mounted on the stays (1). |