| 摘要 |
A support 1 is provided having an expandable enclosure 3 for use in an excavation or trench. The enclosure 3 is expandable on introduction of a fluid. The enclosure is configured such that when the enclosure 3 is in the expanded configuration, and is located in said excavation, pressure exerted by the fluid on an internal surface of the enclosure is sufficient to provide support for a wall of the excavation. The enclosure may be filled with air or gas using a foot pump or electric pump (19, figure 3c). There may be a rigid platform 102 to allow vehicles to cross the trench. |
