| 摘要 |
<p>In "flying forms" having a plurality of trusses-- usually two -- with a plurality of beams placed across the trusses and a deck placed on the beams, an extension leg for the truss is provided so that the working height of the truss may be nearly twice its flying height. The extension leg replaces a truss upright, and mounts using the same bolting arrangement therefor. The leg comprises inner and outer legs, where the outer leg is secured to the top and bottom chords of the truss, and the inner leg is telescopically engaged within the outer leg. The shape of the inner leg is such as to accommodate the bolts which secure the outer leg to the truss chords. Holes are formed in the inner and oouter legs with predetermined spacings, and pairs of pins are used to lock the inner leg in any desired position with respect to the outer leg at substantially the desired height. A screw jack assembly is hingedly secured at the bottom of the inner leg, and may be locked in a downward position for pouring or locked in a swung-up position for flying.</p> |
