Patent ID: 8590830

Claim:
A pressure tight large-scaled membrane structure comprising: a bag body formed from having a plurality of gores; a plurality of first ropes; and a plurality of second ropes, wherein each of the plurality of the gores comprises a middle gore portion and upper and lower gore portions arranged at top and bottom ends of the middle gore portion; the bag body before inflation comprises: a cylindrical-like portion composed of the middle gore portions; an upper bag body portion composed of the upper gore portions; and a lower bad body portion composed of the lower gore portions; the upper and lower bag body portions comprises shapes obtained by dividing a shape according to a relational expression of Euler's Elastica at an equator having a maximum radius thereof; each of the plurality of the first ropes is disposed to the bag body so as to be orthogonal to meridians of the bag body; and each of the plurality of the second ropes is disposed along one of the meridians from a zenith to a nadir of the bag body.