Pre-stressed tension ring structures

Plates of a tension ring and launch connectors are pressed radially outwardly relative to a circular dome supporting structure by thrust bolts mounted by bearing plates secured to anchor bolts embedded in a bond beam supported by columns to pre-tension the tension ring and load the bond beam in compression. The tension ring plates bear against bolts trapped in connector plates clamped to the bearing plates.

DESCRIPTION 
This is a substitute for application Ser. No. 593,708, filed July 7, 1975. 
This invention relates to pre-stressed tension ring structures, and has for 
an object thereof the provision of pre-stressed tension ring structures. 
Another object of the invention is to provide dome structures wherein roof 
domes are integrated with supporting wall structures. 
Another object of the invention is to provide a tension ring structure in 
which a tension ring is pre-tensioned by wall means supporting the ring. 
A further object of the invention is to provide a tension ring structure 
wherein tension ring joints tension a tension ring and pre-stress in 
compression a bond beam forming a part of a wall. 
Another object of the invention is to provide improved tension ring joints. 
Another object of the invention is to provide a tension ring structure in 
which a connector plate adjustable on a bearing plate is rigidly connected 
to a tension ring and is pressed by a thrust bolt to pre-tension the 
tension ring. 
Another object of the invention is to provide improved anchorage of the 
tension ring joints to a supporting structure.

Referring now in detail to the drawings, there is shown therein a 
pre-stressed tension ring structure forming one embodiment of the 
invention and also forming a part of a domed building including a tension 
ring 10, which is pre-tensioned, and tension ring joints 12, connecting 
the tension ring to a bond beam 14 to pre-stress the bond beam in 
compression. The bond beam 14 is a full circle ring of steel reinforced 
concrete and is integral with and supported by columns 16 of the dome 
structure. 
Each tension ring joint 12 includes a bearing plate 20 placed over anchor 
bolts 22 embedded in the bond beam 14, holes 24 fitting closely over the 
bolts. The bearing plate is supported on grout 26. A connector plate 28 
has enlarged holes 30 very loosely receiving the anchor bolts 22, and also 
has hexagonal sockets 32 below bolt holes 34 in a plate 36 welded to the 
connector plate. Bolts 38 have heads 40 fitting in the hexagonal sockets 
32, and extend through the holes 34. Chordal tension ring plates or bars 
42, 44 and 46 have stacked or overlapping end portions with holes 48 
fitting closely over the bolts 38. 
Haunch connectors 50 have base plates 52 resting on the top plate 46 with 
the bolts 38 extending through holes 54 in the haunch base plate. Vertical 
plates 56 of the haunch connectors bear against the overlapping chordal 
plates 42, 44 and 46 of the tension ring. Wood beams 58 are connected to 
abutments 60 of the haunch connectors, and are connected at their other 
ends by hub connectors 62 of the dome per se. 
Thrust bolts or adjustment screws 70 for pre-stressing the tension ring 10 
and bond beam 14 are threaded through lugs 72 of the bearing plates 20 and 
nuts 74 welded to the bearing plates and lugs. The bolts 70 are radial of 
the dome and bear against the connector plates 28 and 36. 
To assemble the dome, with the bearing plates 20 positioned on the grout 26 
and the anchor bolts 22, the bottoms of the connector plates 28 are 
greased, the connector plates with the heads 40 of the bolts 38 in the 
sockets 32 are placed on the bearing plates and over the anchor bolts 22. 
Washer plates 82 are placed over the bolts 22 and under nuts 84, then are 
hand tightened. The tension ring 10 then is assembled by placing the 
chordal plates 42, 44 and 46 on the bolts 38, and the connectors 50 are 
placed on the bolts 38 and tension ring. Erection of the dome skeleton 
against connectors 50 pushes the tension ring radially outwardly removing 
slack and engaging the bolts 38 to the sides of the holes 48 after which 
nuts 80 are wrench tightened on the bolts 38. The thrust bolts 70 then are 
hand tightened and then given one turn with a wrench. Then the sheathing 
or decking is placed on the dome to complete the loading of the tension 
ring. Then the thrust bolts 70 are wrench turned, usually not over two 
turns, to press the connector plates 28 and bolts 38 radially outwardly to 
further tension the tension ring to an intended extent and to place the 
bond beam 14 under compression to the same intended extent. That is, the 
bond beam is pre-stressed in compression and the tension ring is 
pre-stressed in tension. The nuts 84 then are wrench tightened. The nuts 
84 clamp the plate 28 tightly against the bearing plates. Then, when 
further loading occurs on the dome, the tension ring is further tensioned 
and the bond beam after first losing its compression pre-stress also is 
tensioned but to a lesser amount and takes that lesser part of the load 
from the tension ring. To support the portions of the chordal plates 42, 
44 and 46 between the joints 12, suitable grouting pads on the bond beam 
are provided along with wood spacers between the portions of the chordal 
plates above the grouting pads. 
Embodiment of FIGS. 4-7 
A tension ring structure forming an alternate embodiment of the invention 
includes a pre-tensioned tension ring 110, tension ring joints 112, a bond 
beam 114 integral with columns 116 and haunch connectors 150 connected to 
beams 158 and forming part of the dome per se. The tension ring comprises 
pairs of angled plates 142 and 144 spliced to other pairs between the 
tension ring joints 112. Connector plates 128 are clamped tightly to 
bearing plates 120 after thrust bolts 170 have pre-stressed the tension 
ring 110 in tension and the bond beam 114 in compression, large holes 130 
in the connector plates 128 fitting overly loosely over the anchor bolts, 
washer plates 182 and nuts 184 being provided. The plates 144 bear against 
bolts having hexagonal heads trapped in hexagonal sockets in the connector 
plates 128. Nuts 180 on the bolts 138 press base plates 152 of the 
connectors 150 against the tension ring plates 142 and 144, and the thrust 
bolts 170 bear against apices of angular vertical plates 156. Spacers 157 
and 159 separate the plates 142 and 144. 
In FIGS. 6 and 7, spliced portions of and intermediate supports for the 
chordal tension ring plates 142 and 144 are shown. The end portions of the 
plates 142 and 144 are clamped between splicing plates 185, 186 and 187 by 
bolts 188, tie bolts 189 securing the assemblage against purlins 190 and 
heads 191 of the bolts being positioned loosely in clearance sockets 192 
in the purlins. Grouting pads 193 on the bond beam 114 support the 
portions of the purlins secured to the splices of the tension ring to 
prevent sag of the intermediate portions of the tension ring.