Mechanically stripped end shutter for underground concrete walls - has inflatable tubes forcing shutter free of set concrete and forming shaped face for next section

摘要

The trench (1) is excavated and a thick metal shutter (2) is placed on the end. The shutter has deflated reinforced textile tubes (5) and quarter circle hollow metal arches (3) attached to it, the latter being spaced (4) so that a waterproof joint (7) can be forced into it. Concrete is cast into the excavation and when set, the next trench section is excavated. The tubes are inflated, forcing the shutter free, leaving the face of the wall holding the waterproof joint. This is shaped to take the next wall section without differential movement between concrete sections.