US 3919813 A
A self-supporting building structure having a generally hemispherical shape, constructed by a series of panels which are wider at the bottom and curved and tapered so that they are narrower at the top. The panels are locked to a series of curved vertically extending girders by means of spring clips.
Description (OCR text may contain errors)
l Unlted States Patent 11 1 1111 Beindorf [4 Nov. 18, 1975 BUILDING STRUCTURE 2.554.418 5/1951 Mortenson .1 52/495 I 2.741776 4/1956 Peirce 52/495  Inventor' Luna Bemdorf BOX 3.550.335 12/1970 Huffman... 52/82 351, Sprmgfield, 65801 3.616.588 11/1971 Hansson 52/495  Filed: Nov. 17, 1972 I 7 Primary E.\'ammerErnest R. Purser Appl- N05 3072736 Assistant E.\'aminerHenry Raduazo Attorney, Agent, or FirmReuben Wolk  US. Cl. 52/80; 52/82; 52/747 511 int. c1. L04B 1/32 [571 ABSTRACT  Field of Search 52/ 80-83, 495, A self-supporting building structure having a generally 52/747 hemispherical shape, constructed by a series of panels which are wider at the bottom and curved and tapered [56 References Cited so that they are narrower at the top. The panels are UNITED STATES PATENTS locked to a series of curved vertically extending gird- 2.278.956 4/1942 Wagner 52/81 ers by means of sprmg chps' 2.499.478 3/1950 Feser 52/495 16 Claims, 8 Drawing Figures US. Patent Nov. 18, 1975 Sheet 1 on US. Patent Nov. 18, 1975 Sheet 2 013 US. Patent Nov. 18, 1975 Sheet 3 of3 3,919,813
8 I w M BUILDING STRUCTURE BACKGROUND OF THE INVENTION There is a great need for low cost, but strong and practical building structures that are capable of being quickly and easily assembled, and just as capable of quick disassembly. Such structures would be advantageously used as farm buildings, military barracks, low cost homes, storage sheds, greenhouses, garages, hurricane shelters, and a host of other purposes. Many prefabricated structures for on site assembly are in everyday use, although not all of these lend themselves to the simple and quick assembly and disassembly that is so important.
The dome, or hemisphere, is probably the most logical shape for a structure of this type because of the inherent strength and rigidity of such a shape. We see this in natures design of the eggshell, which is an amazingly strong overall structure when one considers the extremely small amount of material in the shell. It is, therefore, quite logical to form structures of this type as a dome somewhat similar to Buckminster Fullers Geodesic" buildings, and as disclosed in U.S. Pat. Nos. 3,085,366 and 3,221,451.
SUMMARY OF THE INVENTION In accordance with the present invention, a dome or semi-hemispherical structure may be assembled more easily than ever before. By means of my novel assembly, the components may be combined with only very simple tools, and these need be used at a minimum. Essentially, the construction procedure is simple and is performed by hand, and permits one man to assemble a 32 ft. diameter structure in about eight to ten hours. The erection can be done quietly, because no sawing, hammering, or riveting is required. The construction is accomplished by erecting a series of vertically extending, curved girders, fastened at their bases to a suitable ground structure, then placing the curved panels against the flanges of the girders and pressing spring clips at intervals between the girders and the panels to lock the panels in place. Each panel is tapered inwardly at the upper end, so that the completed assembly provides a tight, enclosed structure. The upper ends of the girders may be secured to a central member to close off this upper end.
The novel structure also lends itself to the fabrication of rooms within the dome, and in some cases it is possible to form a two-story building by constructing a floor half-way up the dome. Other advantages of the novel structure will become apparent from the description below.
The fundamental theme and basic advantage in my novel invention is the unique combination of very light, low cost materials, that after simple and quick assembly takes on unusually great rigidity and strength against high winds and severe gusts, and in addition, the metal grounded girders and metal connecting cupola at the top junction serves as an almost perfect overall protective shield in the event of being struck by a heavy lightning bolt strike or falling limbs.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of the novel structure. with parts of the outer surface broken away to illustrate certain structural features.
FIG. 2 is a top elevational view of the structure, with parts of the outer surface similarly broken away.
FIG. 3 is a perspective view of the completed struc ture.
FIG. 4 is a sectional view taken along line 4-4 of FIG. 3, illustrating the relationship of the principal components of the structure.
FIG. 5 is a view of a typical method of securing the structural components to the ground.
FIG. 6 is a view of a typical method of securing the girders at the top.
FIGS. 7 and 8 are views similar to FIG. 4 illustrating modified forms of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, reference numeral 11 designates the dome, which is generally in the form of a hemisphere. For optimum stability and ease of construction, the bottom portion of the dome is not at a true right angle to the ground, but is at an angle A, as shown in FIG. 1. This angle should preferably be between 8 and 12. Similarly, the upper portion of the dome is not quite parallel to the ground, but is at an angle B, as seen in FIG. 1, which is about 9 to 13.
The dome is primarily composed of a series of identical girders 13, which are curved from bottom to top in a continuous arch. The exact radius of the curve will vary, according to the size of the structure; as one example, a 32 ft. base diameter dome will utilize girders having a radius of about 20 ft. The exact number and length of the girders will vary with the size of the structure, but a 32 ft. base diameter structure will utilize 24 girders, and is the smallest and most practical size. The dome is completed by identical panels 12 which are placed against the girders as described below, each panel having a base dimension of about 48 in. at the bottom and 3 in. at the top. The panels may be made of any number of materials, usually about /a in. to /8 in. thick, so long as the material provides sufficient strength and rigidity to provide structural integrity. For example, the material may be plywood, metal, composition or plastic; if the structure is to be used as a greenhouse or other structure where light entrance is desirable, a transparent or translucent plastic such as acrylic or methyl methacrylate is desirable. For special effects or purposes, any combination of panels of different ma terials may be employed.
The panels 12 are placed against the girders 13 as shown in FIG. 4. The panels flex to attain the same radius of curvature as the girders, and may also be secured at the lower surface to the ground or a ground structure and taper upwardly and inwardly toward the top of the dome. Great lateral strength and rigidity are thus achieved by these panels, so that the most advantageous features of thin, flexible panels are realized. The girders may also be made of steel, aluminum, magnesium or plastic, and consist ofa small flange 14, a transverse web 14a and a pair of larger flanges l5 and 16 at the opposite end of the web. The small flange 14 has inwardly-turned edges 17 and 18 which create channels 19 and 20 between these edges and the web. The panels are placed inwardly of one large flange 15 of one girder and the large flange 16 of the adjacent girder, as shown in FIG. 4, but before actual placement takes place, the fabricator forms strips of mastic material 21 along the inner surfaces of the flanges. This mastic material serves the dual purpose of sealing the panels to the flanges and aiding in the adhesion thereto. The composition of the mastic material is not critical, but may be a rubber, plastic or asphalt base material which is in the form ofa paste or glue and may be easily applied by a caulking gun or trowel, and readily clings to a vertical surface. Such materials are readily obtainable in hardware stores or lumber yards. It is also possible to use a prepared double-sided contact cement tape.
After each panel is placed against the mastic-lined flanges l5 and 16, it is locked in place by means of spring clips 22, which consist of spring steel of a thickness and length that will lock the panels in place and will still be capable of actuating without the use of excessive force. For example, a typical clip may be about H16 in. thick, /4 in. wide, and 3 in. long. One end ofthe clip is placed within the channels 19 or 20 as shown at the right-hand side of FIG. 4, and the other end is wedged against the panel. The clip in this condition is designated by reference numeral 22a. The clip is then forced inward in the direction of arrow C, preferably by the use of a simple tool such as a small rubber mallet, or by thumb, until it assumes a concave configuration as shown elsewhere in FIG. 4, thus locking the panel in place. For optimum results, pressure should be applied on the clip about one-third the distance in from the panel. For disassembly, the clip may be released by an appropriate tool to free the panel. By means of this novel combination of components, therefore, the panels are locked in place without the necessity for bolting, welding or riveting. as required. for example, in U.S. Pat. No. 3,221,451.
The above description refers to the principal arrangement of the girders, the panels, and the clips. A complete assembly operation will involve additional steps, as follows. A pair of adjacent girders will be attached to some sort of ground structure, either to a pre-existing floor or to footers which have been poured into the ground. As shown in FIG. 5, a bracket 23 may be secured through its horizontal leg 24 to the floor or footer by means of a bolt 26 or similar structure. The girder is then secured to the vertical leg of the bracket by means of bolt 27. The mastic 21 is applied along the inner surfaces of flanges 15 and 16 as described above, and a panel 12 is placed against the thus treated flanges. The installer then places theclips 22 and wedges them in place as described above, locating these clips at spaced intervals of about one foot along the length of the panel. Another adjacent girder is similarly installed, followed by more mastic, an adjacent panel, and another series of spring clips. This procedure is repeated until the structure is enclosed.
As a final step, a circular flange 28 may be secured at the top of the structure. This is secured to a series of brackets 29, each having a leg 30 that is bolted to the flange by means of bolts 32, and legs 31 which are similarly bolted to the web ofthe girders 13. It is, of course, understood that this top flange is only one type of structure used to close off the top of the structure, but that other similar canopy or capping devices may be used. A flange of this type is particularly useful where an exit heating or ventilating pipe is necessary.
The assembly sequence is described in general terms above, but a specific assembly sequence may be described as follows:
Two opposing girders and the top flange are set in place and bolted together, with the bolts remaining slightly loose. Two more girders are set up at 90 from the original ones and also loosely bolted. As a result, a self-supporting, self-aligning structure is standing. The remaining girders will then be set up and loosely bolted in any desired sequence. After this is completed, all bolts are tightened to provide a solid and safe skeleton to which the panels may be secured as described. Any door or window units to be installed are mounted in any desired sequence, before, during or after installation of the panels.
The window and door units may be preformed as a portion of a panel, which may then be substituted for a conventional panel. It is also possible to install these units as partial panels between adjacent girders, and adding a partial conventional panel above or below the special unit between the same girders. These panels will also be locked in place by the same devices as described above.
MODIFICATIONS Many other modifications are contemplated within the scope of this invention, some of which are described below.
FIG. 7 illustrates an assembly similar to the one described above, except that a protective member, such as a soft metal strap 33, is placed over the end of the panel opposite each clip as shown. Each strap is about H16 in. thick by about one inch wide, and has a right angle flange 34 fitting against the edge 36 of the panel, and an oppositely extending flange 35 extending outwardly of the panel. This strap is used on hard panels, such as metal, glass, or acrylic plastic, in order to eliminate slippage of the clip 42. It may also be used on very soft panels, where frequent assembly is contemplated, in order to avoid gouging. When assembling, the clip 42 is placed with one end in the channel 19 and the other end against the strap 33. Pressure is applied against the flange 35 by means of a finger or a sharp tool, with the pressure applied in the direction of arrow At the same time, locking pressure is applied to its clip in the direction of arrow D, to cause the clip to spring into concave position as shown and lock the panel in place. The end of the clip which contacts the strap will dig into the strap to cause it to lock, since the material of the clip is harder than that of the strap. Mastic material 21 is, of course, applied as described above.
FIG. 8 illustrates an assembly utilizing a wedge instead of a spring clip, as a locking means, and has particular value where a permanent or semi-permanent structure is contemplated. In this modification, a wedge 52, formed of a block of wood, plastic or metal, is placed between the panel 12 and the small flange 14. The wedge is first located in the position shown in phantom, so that the small edge 53 is placed in channel 19 and the opposite side 54 is in contact with the panel 12. The block is forced into place, as shown in solid lines, by tapping approximately at the position designated by arrow F" until the opposite side 55 is in contact with the web 14a. This locks the panel securely in place against the flange 15. Mastic material 21 is, of course, applied as described above.
It should be understood that the inventive concept of the present application may also be embodied in further modifications. For example, the spring clips used to lock the panels in place may take on a variety of configurations. Also. although the clips and the wedges are illustrated as being inserted within the channels formed by the small flanges of the girders, other means of locking may be provided, such as punched segments of the 5 web, rivets, etc. In each case, the locking members are somehow locked adjacent the end of the web which is opposite the large flanges. This provides for a girder construction which lacks the small flanges illustrated above.
1. A building structure comprising a plurality of inwardly arched structural members in the form of gener' ally T-shaped girders each having a transverse web and a pair of flanges extending outwardly from one end thereof, similarly arched panels placed against the inner surfaces of said flanges to form a generally hemispherical configuration, locking members extending outwardly from the other end of said webs and forming channels therewith, and locking means securing said panels to said structural members, one end of said locking means placed adjacent the inner surface of a panel and the other end being inserted within one of said channels, said structure including a further member at its upper surface at which said structural members are secured, said further member providing open access to the interior of said structure.
2 The structure of claim 1 in which said panels are tapered inwardly toward their upper surfaces.
3. The structure of claim 1 in which said locking means consist of a plurality of spring clips.
4. The structure of claim 1 in which said locking means consist of a plurality of wedges.
5. The structure of claim 1 including sealing means between said panels and said flanges.
6. The structure of claim 1 in which said locking means consist of a plurality of spring clips, said structure further including a plurality of protective members placed over one end of said panels, one end of each clip placed adjacent a corresponding member and the other end of each clip locked adjacent the end of the web which is opposite said flanges.
7. The structure of claim 1 in which said panels are formed of a translucent plastic material.
8. The structure of claim 1 in which said panels are formed of metal.
9. The structure of claim 1 in which the lower ends of said structural members are secured to a common ground surface.
10. The structure of claim 1 in which said panels are arched in a generally upward and inward direction but extend in a flat plane between adjacent girders.
11. The structure of claim 1 in which said locking means consist of a plurality of spring clips, the end of said clips adjacent the inner surfaces of the panels extending approximately at right angles to said panels.
12. The method of assembling a generally hemi spheric building structure comprising the steps of erecting a plurality of inwardly arched structural members in the form of generally T-shaped girders each having a transverse web and a pair of flanges extending outwardly from one end thereof and locking members extending outwardly from the other end thereof and forming channels therewith, placing similarly arched panels against the inner surfaces of said flanges. placing locking means against said panels and said structural members to provide a unitary structure by applying one end of said locking means adjacent the inner surface of said panels and inserting the other end of said locking means within one of said channels, and applying pressure to said locking means to lock said panels to said girders.
13. The method of claim 12 in which said pressureapplying step causes a change in the configuration of said locking means.
14. The method of claim 12 including the step of applying sealing means between said panels and said flanges.
15. The method of claim 12 including the step of securing the upper ends of said girders to a centrally located member.
16. The method of claim 12 including the step of securing the lower ends of said girders to a common