Abstract: An edge clamp assembly for an inflatable form membrane used in erection of a concrete shell comprises a steel channel having an internal width W mounted at the base of the shell with the longitudinal opening of the channel facing upwardly; a guide lip on one channel leg projects a short distance over the channel opening. A first rectangular wood rail is wrapped in an edge portion of the membrane and inserted into the channel, fitting loosely into the bottom of the channel; a second rectangular wood rail having a width just slightly smaller than W is inserted into the top of the channel, tightly filling the channel opening immediately below the guide lip and releasably clamping both rails and the edge portion of the membrane into the channel.

Abstract: A method and apparatus for anchoring an inflatable membrane form to the base wall of a building to be covered by a concrete shell incorporates a groove formation at the top inner face of the building base wall, the groove formation comprising a horizontal shelf of width W1, a recess of height H1 and width W2, and a vertical wall segment of height H2. The edge portion of an inflatable membrane form is wrapped in a multiplicity of elongated wood rail members of height H3 and width W3, with H3<H1 and W1>W3>W2, and the rails are inserted into the groove formation recess. A multiplicity of elongated steel retainer plates of flat, open, C-shaped cross-sectional configuration, mounted on bolts projecting from the shelf portion of the groove formation, aid in holding the wrapped rails and form edge in place when the form is inflated.