Pneumatic load-supporting structures

Claim 2

A pneumatic structure, comprising: a. an inflatable envelope having opposed, spaced upper and lower membranes; b. a plurality of vertical diaphragms connected between said first and second membranes, said diaphragms being at least semi-elliptical with top and bottom curved edges that diverge from a common point with respect to the major axis of the ellipse, said diaphragms being reinforced vertically and being operable to resolve the vertical component of forces applied to the top of the envelope; c. a plurality of upper cables, each upper cable being connected to the top edge of a diaphragm at the junction of the diaphragm and the first membrane; d. a plurality of lower cables, each lower cable being connected to the bottom edge of a diaphragm at the junction of the diaphragm and the second membrane; e. said upper and lower cables of each diaphragm being connected to each other near the periphery of said envelope; f. means for inflating said envelope; and g. said cables and said diaphragms coacting to carry the load applied to the top of the envelope when inflated.

Claim 3

The structure according to claim 1, wherein the envelope, when inflated, is ellipsoidal, each diaphragm defining a semi-ellipse, and there is provided a central support, and top and bottom anchor means affixed to the support, the ends of the upper and lower cables remote from the periphery of said envelope being connected to said top and bottom anchor means, respectively, and the diaphragms being connected to said central support.

Claim 4

The structure according to claim 2, wherein the diaphragms are reinforced horizontally and vertically.

Claim 5

The structure according to claim 1, wherein at least some of the diaphragms are parallel.

Claim 6

A roof structure, comprising the pneumatic structure according to claim 1, which is inflated and which is supported by a plurality of vertical support columns around the periphery thereof, the lower cables being suspended from the columns.

Claim 7

The roof structure according to claim 5, including a compression ring means connected to said columns.

Claim 8

The roof structure according to claim 6, wherein said compression ring means is a pneumatic compression ring means comprising an inflated toroidal envelope having reinforcing means for relieving circumferential tension therein, said compression ring being supported by said columns through a plurality of looped cables extending circumferentially around sid toroidal envelope and attached via a hanger cable to said column, the looped cables being connected to a balancing cable extending around the peirphery of the roof, and said lower cables are suspended from said balancing cable.

Claim 9

The roof structure according to claim 7, wherein said reinforcing means are circular tension hoops spaced axially around said toroidal envelope.

Claim 10

The roof structure according to claim 7, wherein said reinforcing means are circular diaphragms connected to said toroidal envelope and spaced axially around the toroidal envelope.

Claim 11

The roof structure according to claim 7, wherein the reinforcing means is provided by pre-stressing the toroidal envelope to form a series of arcs of less than 180° spaced axially around the toroidal envelope.

Claim 12

The structure according to claim 3, wherein, under no live load conditions, said diaphragms are operable to carry approximately half of the horizontal pressure load on the surface of the inflated envelope and the lower cables are operable to carry the other half, whereby the structure is self-correcting for changes in shape.

Claim 13

A pneumatic structure, comprising: a. an inflatable envelope having opposed, spaced upper and lower membranes, said envelope, when inflated, being ellipsoidal; b. a plurality of vertical diaphragms connected between said first and second membranes, each diaphragm defining a semi-ellipse with top and bottom curved edges that diverge from a common point with respect to the major axis of the ellipse; c. a plurality of upper cables, each upper cable being connected to the top edge of a diaphragm at the junction of the diaphragm and the first membrane; d. a plurality of lower cables, each lower cable being connected to the bottom edge of a diaphragm at the junction of the diaphragm and the second membrane; e. said upper and lower cables of each diaphragm being connected to each other near the periphery of said envelope; f. means for inflating said envelope; g. a central support, and top and bottom anchor means affixed to the support, the ends of the upper and lower cables remote from the periphery of said envelope being connected to said top and bottom anchor means, respectively, and the diaphragms being connected to said central support; and h. said cables and said diaphragms coacting to carry the load applied to the top of the envelope when inflated.

Claim 14

A pneumatic structure, comprising: a. an inflatable envelope having opposed, spaced upper and lower membranes, said envelope, when inflated, being ellipsoidal; b. a plurality of vertical diaphragms connected between said first and second membranes, each diaphragm defining a semi-ellipse with top and bottom curved edges that diverge from a common point with respect to the major axis of the ellipse; c. a plurality of upper cables, each upper cable being connected to the top edge of a diaphragm at the junction of the diaphragm and the first membrane; d. a plurality of lower cables, each lower cable being connected to the bottom edge of a diaphragm at the junction of the diaphragm and the second membrane; e. said upper and lower cables of each diaphragm being connected to each other near the periphery of said envelope; f. means for inflating said envelope; g. a central support, and top and bottom anchor means affixed to the support, the ends of the upper and lower cables remote from the periphery of said envelope being connected to said top and bottom anchor means, respectively, and the diaphragms being connected to said central support; and h. said cables and said diaphragms coacting to carry the load applied to the top of the envelope when inflated.

Claim 15

A roof structure, comprising the pneumatic structure according to claim 12, which is inflated and which is supported by a plurality of vertical support columns around the periphery thereof, the lower cables being suspended from the columns.

Claim 16

The roof structure according to claim 13, including a compression ring means connected to said columns.

Claim 17

The roof structure according to claim 14, wherein said compression ring means is a pneumatic compression ring means comprising an inflated toroidal envelope having reinforcing means for relieving circumferential tension therein, said compression ring being supported by said columns through a plurality of looped cables extending circumferentially around said toroidal envelope and attached via a hanger cable to said column, the looped cable being connected to a balancing cable extending around the periphery of the roof, and said lower cables are suspended from said balancing cable.

Claim 18

The roof structure according to claim 15, wherein said reinforcing means are circular tension hoops spaced axially around said toroidal envelope.

Claim 19

The roof structure according to claim 15, wherein said reinforcing means are circular diaphragms connected to said toroidal envelope and spaced axially around the toroidal envelope.

Claim 20

The roof structure according to claim 15, wherein the reinforcing means is provided by pre-stressing the toroidal envelope to form a series of arcs of less than 180° spaced axially around the toroidal envelope.