US3688327A

US3688327A - Cellular building structure

Info

Publication number: US3688327A
Application number: US58213A
Authority: US
Inventors: Rolf F Marshall
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-07-27
Filing date: 1970-07-27
Publication date: 1972-09-05
Anticipated expiration: 1989-09-05

Abstract

A cellular building structure comprised of a multiplicity of cells, each cell in the structure being a substantially fully enclosed unit and having a regular geometric cross-sectional configuration. The cells are situated around and in close proximity to one another with the sides of any one of the cells being at an angle supplementary to a side of another one of the cells, where the supplementary sides are adjacent and parallel to one another to form a compartmentalized cell structure, or where adjacent cells share a common side.

Description

Elite States atent [151 3,688,327

Marshall Sept. 5, 1972 [54] CELLULAR BUILDING STRUCTURE 3,301,149 1/1967 Box ..52/615 X [72] Inventor: Rolf R Marshall 2 warremon 3,323,797 6/1967 Horton ..52/615 X Court Huntington NY 11743 2,412,778 12/1946 Kosek ..52/618 X 2,641,449 6/1953 Antony ..52/236 X [22] Filed: July 27, 1970 Primary Examiner.lacob L. Nackenhoff [21] Appl' 58213 Att0rneyLee C. Robinson, Jr.

[52] US. Cl. ..14/1, 14/19, 52/618 [57] ABSTRACT 3 A cellular building structure comprised of a multiplici- 1 18 6 ty of cells, each cell in the structure being a substantially fully enclosed unit and having a regular geometric cross-sectional configuration. The cells are situated [56] References cued around and in close proximity to one another with the TE STATES AT S sides of any one of the cells being at an angle supplementary to a side of another one of the cells, where 2,745,520 5/1956 Boutard ..52/237 the Supplementary sides are adjacent and parallel to 3,529,394 9/1970 Wilklns ..52/618 X one another to form a compartmentalized cell struc ture, or where adjacent cells share a common side. o e 3,103,025 9/ 1963 Gassner ..14/ 1 8 Claims, 19 Drawing Figures TENTH! SEP 5 I972 SHiEI 1 BF 5 PATENTEDSEP 5 I972 sum 2 or 5 OUTFLOW PATENTED SE? 5 I972 SHEET 5 OF 5 CELLULAR BUILDING STRUCTURE BACKGROUND OF THE INVENTION Many structures are sensitive to their own weight and are limited in their overall size because of the weight of the material employed to manufacture the structures. Structures such as bridges, roofs and floor spans, loading ramps, towers, masts, booms, transmission lines, ducts, and others are often limited in their overall size because of the weight of the material employed to fabricate the structure. For example, in the case of bridges, a roadway portion of the bridge carries the weight of the vehicles traveling over the bridge. The roadway is usually supported by a number of towers and support cables. Were it not for these towers and support cables, the weight of the roadway would often be greater than the inherent strength of the roadway, thereby causing the roadway to fall.

Similarly, in radio towers, and the like, the tower should be capable of supporting its own weight as well as the weight of the antennas attached thereto. It is not practicable, in most circumstances, to increase the amount of structural material used to build the tower. This usually results in a commensurate increase in weight. One possibility is to employ materials having high strength and stiffness properties, and a low weight. However, such materials are rare and when found may often be excessively expensive.

Structures are usually supported by means of guide cables, support cables, and support columns, as well as high strength reinforcement. It is desirable to have structures which are capable of supporting their own weight with a minimum of external aid from support columns and support cables. Certain types of shell structures have been employed satisfactorily to provide structures having a high strength to weight ratio and a high stiffness to weight ratio. For example, many airplane wings comprise a skin of either metal, wood or some other material which has been suitably internally stabilized. Such a structure will transmit the tensile, compressive and shear stresses resulting from loads applied to the structure without the need of a separate and independent load carrying external structure. However, shell structures of this type have not been readily adaptable heretofore for use in building structures of the type to which the present invention is directed.

BRIEF DESCRIPTION OF THE INVENTION The invention relates to a cellular building structure comprising a multiplicity of cells. Each cell has a substantially regular geometrical cross section. The geometrical configuration of the cells is dependent on the number of cells employed and the configuration of the other cells. The cells are situated with respect to one another with a side of one of the cells being at a first angle and a side of an adjacent cell being at an angle which is supplementary to the angle of the side of the first cell. The adjacent sides are disposed in close proximity to one another, with the planes of the adjacent sides parallel to one another, or else the adjacent cells share a common side.

Each one of the cells, when it is used in the structure, is a substantially totally enclosed structure. The walls of each one of the cells may be composed of a sandwich panel having a light weight core acting as a stabilizing and strength element and a facing sheet disposed along either side of the core. The facing sheets may be composed of a variety of materials depending on the desired surface characteristics of the sandwich panel.

One variety of structure in which the invention may be employed is in the building of bridges. A tubular conduit having a hexagonal cross sectional configuration is assembled having each of its six sides manufactured from sandwich panels or other light weight substances. A multiplicity of hexagonal conduits each having a cross sectional area substantially similar to the first conduit are disposed parallel to the first conduit around its periphery. The hexagonal conduits are situated with respect to one another such that selected sides of adjacent conduits form supplementary angles with respect to one another. The cross section of the overall assembly thus exhibits a honeycomb configuration.

Each of the hexagonal conduits may have a horizontal running surface therein which extends longitudinally of the conduit. The composite honeycomb conduit assembly is relatively self-supporting and provides a structure having a high strength-to-weight ratio and a high stiffness-to-weight characteristic. The composite structure may be employed as a bridge, for example, with fewer supports than would otherwise be necessary with conventional construction techniques.

It is an object of this invention to provide an improved cellular building structure comprising multiple cellular units which are joined together to supplement one another..

Another object of this invention is to provide a cellular building structure which may be quickly and easily erected at the building site and is economical to maintain.

It is a further object of this invention to provide a cellular building structure comprising a plurality of hexagonal conduits joined together to yield a resultant structure having a high strength-to-weight ratio and a high stiffness-to-weight characteristic.

It is another object of this invention to provide a cellular building structure which may be employed in the design of bridges and similar spanning structures.

It is a further object of this invention to provide a hexagonal conduit structure having a multiplicity of hexagonal conduits, each hexagonal conduit having a road surface upon which vehicles may travel.

It is a still further object of this invention to provide a hexagonal cellular conduit structure in which the individual hexagonal cellular conduits may be added to one another to form the cellular conduit structure and provide new road surfaces as the need arises.

It is a further object of this invention to provide a hexagonal cellular conduit structure to form a light weight, stiff, enclosed bridge structure, having a multiplicity of hexagonal cellular conduits, each one of the hexagonal cellular conduits having walls which are composed of a honeycomb or other light weight core having facing sheets on either surface of the core.

The present invention, as well as further objects and advantages thereof, will become more fully apparent from the following description of certain illustrative embodiments, when read with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bridge structure hav ing a number of hexagonal cellular conduits according to one embodiment of the invention.

FIG. 2a is a schematic end view of the conduits as seen from line 2a2a of FIG. 1.

FIG. 2b is a schematic end view similar to FIG. 2a but showing a hexagonal cellular conduit structure according to another embodiment of the instant invention.

FIG. 3 is a perspective view, with a portion shown broken away and in section, of one of the walls of a hexagonal cellular conduit according to the invention.

FIGS. 4a and 4b are schematic representations similar to FIG. 20 but showing an air circulation system for the conduits.

FIG. 4c is a diagrammatic perspective view of one of the hexagonal cellular conduits shown in FIG. 1.

FIG. 5 is an enlarged fragmentary view taken along line 5-5 of FIG. 40 showing a corner support structure.

FIG. 6a is an enlarged vertical sectional view of one of the interconnections between adjacent conduits.

FIG. 6b is an enlarged fragmentary sectional view of a representative interconnection between two panels of one of the conduits.

FIG. 7a is an enlarged fragmentary sectional view of a tenon joint for securing adjacent honeycomb panels which are lying in the same plane to one another.

FIG. 7b is an enlarged fragmentary sectional view of a butt joint for securing the ends of adjacent honeycomb panels which are lying in the same plane.

FIG. 8a is a fragmentary side elevational view of a portion of the bridge structure shown in FIG. ll.

FIG. 8b is an enlarged fragmentary sectional view taken along line 8b--8b of FIG. 8a showing one variety of a honeycomb expansion joint which may be employed between the panels.

FIG. 9 is a diagrammatic representation of a supported bridge structure in accordance with a further embodiment of the instant invention.

FIG. 10 is an enlarged fragmentary perspective view of a portion of one of the towers of FIG. 9 showing a transfer structure which may be employed in conjunction with the cellular tubs.

FIG. 11 is an enlarged fragmentary cross section taken along line 11-11 of FIG. 10 showing an expansion joint of the transfer structure.

FIG. 12 is a perspective view of the cellular bridge structure detailing a hanger structure which may be used to support the cellular bridge tube.

FIG. 13 is a perspective view of a cellular tube bridge having a tower spaced framework where the cellular tube forms a compression boom.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS OF THE INVENTION As is well known, a bridge is subject to a static gravity load, a live load, and a load imposed by weather factors. The static gravity load is imposed by the weight of the bridge itself. The live load constitutes the weight of the vehicles traveling over the bridge and represents a minor proportion of the total load. Conventional truss structures manufactured from steel and other heavy weight materials impose a tremendous burden on the bridge spans and on the supports for the bridge. By employing a sandwich building material having a core and facing layers and by joining the sandwiches together in a hexagonal cellular conduit arrangement to form a light weight, enclosed bridge structure, the static gravity loading is substantially decreased with a corresponding reduction in the necessity for extensive structural support.

Making reference to FIG. 1, there is shown a cellular bridge tube 20 comprised of seven hexagonal cellular conduits 22. A number of foundations 24 are distributed along the path of the tube 20. Each of the foundations 24 may be made of masonry, steel, concrete or other suitable material. At least one tower 26 extends upwardly from each foundation. The towers 26 are substantially the multiplicity of elements used in contemporary truss masonry or concrete structures. Furthermore, the total capacity of the tube 20 can be expanded in response to traffic growth by the addition of new hexagonal cellular conduits 22 to the initial cluster of conduits. This permits the original outlay of capital to be more closely fitted to the existing traffic demand, thus minimizing the period of uneconomical operation, due to overcapacity, which is often experienced in the early years of the operating life of a bridge.

As can best be seen in FIG. 2a, a cluster of seven hexagonal cellular conduits 22 is arranged in a substantially cellular array. Each of the conduits 22 is composed of six side panels 34. Because each conduit has a cross section in the form of a regular, equiangular, equilateral hexagon, adjacent panels 34 meet along their longitudinal edges at an interior angle of As best seen in FIGS. 10 and 12, when one of the conduits 22 is placed adjacent to a second conduit 22, with one of the panels 34 of the first conduit in facing contact with one of the panels 34 of the second conduit over their entire joint length, the exterior angle formed by the panels 34 which are adjacent to the facing panels 34 is also 120. This permits another hexagonal cellular conduit having an interior angle of 120 to be situated within the 120 groove thus formed. When, however, adjacent conduits share a common panel (see FIG. 2a the angle between consecutive shared panels is also 120".

In a second cellular configuration shown in FIG. 2b, the cellular bridge tube 20 is composed of four of the hexagonal cellular conduits 22. However, rather than having apexes in the vertical direction, two of the flat panels of each conduit are disposed perpendicular to the vertical axis. A road surface 32 is defined by a horizontally disposed intermediate panel 54. If desired, a second road surface 35 may be formed by the inner face of the lower of the two panels.

In the arrangement of FIG. 2b two of the hexagonal cellular conduits 22 are disposed one above the other in the same orientation. This will form a set of exterior angles between the conduits of 120. Each of these angles is equal to the interior angle of a third and a fourth hexagonal cellular conduit 22. These latter conduits may be inserted within the external angles formed by the first two hexagonal cellular conduits 22.

As can be seen in FIG. 2b, a set of retaining walls 38 are disposed along the length of the road surface 32.

The retaining walls 38 form an angle of approximately 60 with the road surface 32 in the direction of the panel 34 nearest to the retaining wall 38. Therefore, each of the retaining walls 38 forms one leg of an equilateral triangle with the adjacent panel 34 and the adjacent road surface 32. The retaining walls 38 provide a safety barrier should a car run off the roadway 32. The car will rebound from one of the retaining walls 38 rather than hit one of the panels 34 and possibly injure the structural configuration of the cellular bridge tube 20. Similar rebound walls are formed by the sloping panels 34 for the lower road surface 35.

Each panel 34 is comprised of a central core 40 (FIG. 3). A first facing sheet 42 is disposed on one side of the core 40, and a second facing sheet 44 is disposed on the other side, parallel to the first sheet 42. The core 40 is comprised of a multiplicity of tubular elements 46. Each one of the tubular elements 46 has a central longitudinal axis L in the center of the particular tubular element 46 and running the length of the tubular element 46. The tubular elements 46 are situated parallel to one another with the central longitudinal axis L of each of the tubular elements 46 parallel to the axis L of each of the other tubular elements 46. The tubular elements 46 may be bonded together or fused together. The core may also comprise a foam infrastructure or other suitable stabilizing medium.

The tubular elements 46 may be made from a metal foil, such as aluminum alloy, magnesium alloy or steel, and formed into a honeycomb of cells of hexagonal, square, triangular, or circular form or a variant or a combination of these shapes. Plastic filament composite or resin impregnated materials, such as paper or fabric, may be molded into a honeycomb of cells. The central core 40 acts as a stabilizing element to maintain the separation between the facing

sheets

42, 44. The first facing sheet 42 is a sheet of material having a high tension, compression and shear strength. Materials such as steel, aluminum alloy, magnesium alloy, plastic, and composite materials, such as filament reinforced plastic, filament reinforced metals and resin impregnated fabrics and papers, may be used for facing sheets.

Although the facing sheet 42 has a high compression, tension, and shear strength, it may be thin. The strength developed in the panel 34 is due to the stability influence of the central core 40 which forms the main thickness of the panel. The first facing sheet 42 is bonded to the central core 40 along one of its planar surfaces in a plane transverse to the central longitudinal axis L of each of the tubular elements 46. The second facing sheet 44 is similarly bonded to another face of the central core which is also transverse to the central longitudinal axis L of each of the tubular elements. Thus, the facing sheets are parallel to one another and separated by a distance substantially similar to the height along the longitudinal axis L of the tubular elements 46.

The first facing sheet 42 and the second facing sheet 44 may be of substantially different materials and have different thicknesses. For example, in the cellular arrangement of FIG. 2b, one of the horizontal panels of the conduits 22 serves as a road surface 32. Therefore, one of the facing sheets 42 which is used on the panel should be of a material having a high resistance to wear. The other facing sheet on that panel will be facing downwardly and will be exposed to little wear and only to ambient conditions. Therefore, the second facing sheet 44 may be of a lighter material and may be of a material which does not have as high a compressional, tensile and shear strength as the material used on the first facing sheet 42.

The central core 40, and particularly the individual tubular elements 46 of the central core 40, support and stabilize the first or inner facing sheet 42 and the second or outer facing sheet 44. The facing

sheets

42 and 44 transmit tensile, compressional and shear loads acting on the facing sheets in the plane of the sheets. The adhesive bond for fusing the facing sheets and the core should be capable of transmitting these tensile, compressional and shear loads so that the sandwich will function as an integral unit. This will help in minimizing premature elastic instability failure arising in the panel 34 in the form of buckling due to tension waves and crippling under compressional waves.

The panel 34 behaves like a basically solid panel of the same overall thickness, but with a much reduced weight due to the low density core.

Six panels 34 are arranged to abut edgewise to form the hexagonal cellular conduits 22 through which the bridge traffic can pass. A number of the conduits 22 are joined together in a cluster to form the cellular bridge tube 20. The number of conduits which are joined together is dependent on the traffic flow which needs to be accommodated.

Because the cellular bridge tube 20 comprises a number of enclosed road surfaces 32, it is preferable to provide exhaust and ventilation means within the tube, particularly with respect to the centrally located hexagonal cellular conduits 22.

A ventilation system is provided in each of the hexagonal cellular conduits 22 which provides a flow of air through that conduit. Ventilation openings 48 (FIG. 4c) are located at spaced intervals along the abutting edges of the panels 34 of each conduit. The ventilation openings 48 have duct work (not shown) leading to a central ventilation duct system, As can best be seen in FIGS. 4a and 4b, there is provided a multiplicity of ducts, generally labeled 52, which communicate between the atmosphere outside of the cellular bridge tube 20 and the ventilation openings within the conduits 22. As traffic passes along the road surfaces 32 within each one of the conduits, the traffic creates a flow of air through each conduit. This flow of air tends to create a partial vacuum behind the moving vehicle and set up currents which draw cool air from the outside (as can be seen from the solid lines in FIGS. 4a, 4b and 4c). As the air becomes hotter and filled with noxious fumes, it will tend to rise within each one of the conduits 22. This will place the air in contact with the upper ventilation openings 48 which will allow it to exit from the conduit to the outside. As the cellular bridge tube 20 is increased in size, it may be desirable to substitute a pumping system for forcing air into the various conduits rather than rely on the current set up by the flow of traffic.

A hexagonal cell provides a suitable cross sectional shape to accommodate vehicles. In the cellular arrangement shown in FIG. 2a and FIG. 5, each of the conduits 22 is provided with a road surface 32. The

road surface 32 is formed on the a road panel 54 positioned between two nonconsecutive edges of the lowermost panels 34 of each conduit. The road panel 54 is horizontal and spans the width of the cell.

As best shown in FIG. 5, there is an open space between the outer facing sheets 44 on adjacent panels 34, while the inner facing sheets 42 are in contact. The space between the outer sheets is closed by a bridging panel 56 which spans the distance between the adjacent sheets 44. Two angle members 58 are respectively situated on the facing ends of each pair of adjacent panels 34. Each of these angle members is affixed to both the bridging panel 56 and the panel 34 along their entire length.

The bridging panel 56 is comprised of a central core 40b (FIG. 6b). The central core may comprise a multiplicity of tubular elements or may comprise a foam infrastructure. An inner facing sheet 42b and an outer facing sheet 44b are bonded to the inner and outer surfaces of the central core 40b. The facing sheets 42b and 44b are parallel to one another and parallel to a plane which is transverse to the central longitudinal axis of the tubular elements of the bridging panel.

A set of angles '74 join the outer facing sheet 44 of the panels 34 to the outer facing sheet 441) of the bridging panel 56. The angles run along the abutting edges of the facing sheets. The angles 74 may be bonded to the outer facing sheets, or may be secured by conventional means, such as rivets.

The road panel 54 has a central core 400, an upper facing sheet 42a and a lower facing sheet 44a (see FIG. The road surface 32 is disposed above the upper facing sheet 42a. Light-weight roadways may be employed, such as crystalized silica, or sand added to a surfacing resin which bonds to the upper facing sheet. This type of treatment yields a highly attractive paving about one-fourth inch thick with wearing qualities comparable to several inches of much heavier concrete or bituminous materials.

A roadway support girder 60 extends longitudinally intermediate each end portion of the roadway panel 54 and the panel 34 therebeneath. The girder 60 is affixed to the lower facing sheet of the roadway panel 54 and to the upper sheet of the panel 34. The girders 60 support the roadway panel 54 to prevent it from being displaced in the horizontal direction.

An angularly extending side wall, generally labeled 62, is disposed along the lateral extremities of the roadway panel 54- where the roadway panel 54 contacts the cellular conduit panels 34. The side wall 62 is comprised of a facing sheet 64 and a crushable filler material 66 intermediate the facing sheet 64 and the panel 34. If a vehicle should happen to slide off of the road surface 32, it will hit the side wall 62, and rather than damage one of the panels 34 it will crush the crushable filler material 66, thereby absorbing the primary force of the impact.

A hinge 68 is situated at the abutting inner facing sheets 42 of the panels 34. The hinge 68 serves as a panel joint to connect the inner facing sheets 42 of the panels 34. The area beneath the roadway panel 54 is available for services and ducts.

The triangulated joints formed when the edges of three panels 345 abut form areas of great rigidity. These triangulated joints, combined with the stiff sandwich panels 34, result in a structure which is relatively stiff under bending and torsion loads. The triangulated joints are best shown in FIG. 6a. In FIG. 6a, three panels 34 having longitudinal edges E come together such that the edges E form a triangulated joint.

A closing section 70 is secured to the ends of each one of the panels 34 to form the edge E. The closing section is intermediate the inner sheet 42 and the outer sheet 44 of the panel and encompasses the central core 40. The closing section protects the central core from injury and stiffens the edges of the panel. A continuous angle or hinge 72 is affixed to the sides which abut one another along the longitudinal edge E. The hinges may be fused to the outer surfaces of the facing sheets or may be secured to the outer surfaces of the facing sheets by means of conventional bolt or other fastening arrangements.

The panels 34 may be of a great length and can even be of a length equal to the distance to be spanned. However, the panels will usually be of a shorter length. This necessitates joining panels 34 along the length of the conduit.

One such joint is a tenon joint, as best illustrated in FIG. 7a. This tenon joint is useful for securing panels together which lie in the same plane. Doubler plates 78 are affixed to the inner surfaces of the inner facing sheets 42 and the outer facing sheets 44 of the panels to be joined. The doubler plates are coterminous with the ends of the panels and extend parallel to the facing sheets from the ends thereof into the core material 40 for a length P.

A closing section 70 encompasses the central core and extends outwardly from the end of the panel 34a. The closing section 70 protrudes into the core material and is disposed adjacent the upper and lower doubler plates 78. A closing section 71 encompasses the central core of the panel 34b and is adjacent to both of the doubler plates 78. A set of mechanical fasteners 76 join the inner and outer facing sheets and the doubler to the closing section of the first panel 34a.

A second type of transverse panel joint is shown in FIG. 4b. This type of panel joint, referred to as a butt joint, includes a first doubler plate 78 bonded to the inner side of the inner facing sheet 42 and a second doubler plate bonded to the inner side of the outer facing sheet 44, of each of the panels to be joined. Each doubler plate is intermediate one facing sheet and the central core. The doubler plates extend from the end of the

respective facing sheets

42, 44 inwardly a distance D. A closing section 7th is bonded to the end of the central core of each panel. The closing section 70 has a frontal edge 75 which is parallel to the central longitudinal axis of the tubular elements 46 of the central core. The frontal edge is coterminous with the ends of the doubler plates and the ends of the inner and the outer facing sheets.

An L bracket 7 is secured to the outer surface of the inner facing sheet 42 and the outer surface of the outer facing 44 of each of the panels 34a and 34b. One leg of the U bracket is parallel and adjacent to the

respective facing sheets

42, 44, while the other leg of the L bracket is parallel to and in the same plane as the frontal edge 75. The L brackets are secured to the panels 34a, 34b, by means of mechanical fasteners 76 which pass through the L" brackets and into the panels. A second set of mechanical fasteners 80 are passed through the facing legs of the L brackets to secure the first panel 34a to the second panel 34b.

Provision is made for expansion and contraction of the cellular bridge tube 20. In particular, a variety of transfer structures may be employed to allow sections of the cellular bridge tube to be joined and to accommodate expansion joints between the sections of the cellular bridge tube 20. In FIG. 80, there is shown a cellular bridge tube supported by a foundation 24 of masonry and a tower 26 of prestressed concrete or steel. The tower 26 is mounted on the foundation 24 and extends upwardly therefrom. A cradle 82 is located at the uppermost extremity of the tower 26. The cradle 82 has an upper surface 84 which has a configuration which supplements the outer peripheral configuration of the cellular bridge tube 20. Two

sections

20a and 20b of the cellular bridge tube 20 are slidably mounted on the cradle 82. Connector panels 85 are disposed intermediate the two sections of the bridge tube. The connector panels are rigidly affixed to the individual conduit panels in one of the sections and are slidably situated within the conduit panels in the second sectron.

The interconnections between the panels can best be seen in FIG. 8b. One of the panels 340 in the first section 200 has a core structure 400. The core structure is provided with a U" shaped recess along the edge of the panel which accommodates a closing section 70 and a set of slide walls 88. A set of end closing sections 90 is disposed intermediate the facing plates and the slide walls.

The corresponding panel 34d in the second section of the tube has a similar configuration. However, the closing section 70 has been omitted from the panel 34d, and the facing plates 88a are somewhat shorter than the plates 88.

The connector panel 85 is comprised of a central core 92 and a set of parallel facing sheets 94 and 96 disposed parallel to one another and transverse to the central longitudinal axis of the central core 92. The distance between the outer surfaces of the facing sheets 92 and 94 is substantially similar to the distance between the inner surfaces of the slide walls 88 and 880. A set of connector closing sections 86 is bonded to the ends of the connector panel 85 intermediate the facing plates 04 and 96 and coterminous therewith. The section 86 on the left end of the panel 85 is disposed in spaced relationship with the section 70.

One end of the connector panel 85 is rigidly secured within the U shaped cavity of the panel 34d. The other end of the connector panel 85 is slidably situated within the U shaped cavity formed in the panel 34c. The

panels

34c and 34d are separated by a distance I and may expand and contract without changing the overall length of the cellular bridge tube 20. Expansion dams (not shown) may be employed between the roadway panels to compensate for expansion in the individual panels. Various expansion devices may be employed with and are within the scope of the instant invention.

The concept of this invention may be applied in a number of types of bridges. For example, as can be seen in FIG. 1, the cellular bridge tube 20 may be employed in a pier supported bridge. A relatively short to medium span of bridge tube is supported at intervals by towers topped by cradle structures. At either end of the tube, the conduits are separated from one another and form approach ramps, or exit ramps. Expansion joints as well as roadway expansion dams are provided, as necessary, at the tower and cradle structures, as is shown in FIG. 8a.

A second type of bridge is the suspension bridge, as is best illustrated in FIG. 0. The suspension bridge comprises a long central span of cellular bridge tube 20 suspended from a network of catenary cables 100. Hanger cables 102 extend downwardly from the catenary cables 100 and are secured to the outer periphery of the cellular bridge tube 20. The catenary cables 100 are in turn supported by two towers, generally labeled 104. The tube passes through each one of the towers 104 through a transfer structure 106 situated within each tower. A set of anchor cables 108 is located between each tower and the shore. One end of each of the anchor cables is secured to the uppermost portion of the tower 104, and the other end of the same anchor cable 108 is secured to a shore anchor 110. The majority of the torsion and lateral loads, and some of the local vertical loads over the center span of the cellular bridge tube 20, are transmitted to the towers 104 at either end of the center span of the cellular bridge tube 20. The loads are transmitted at the point where the tube meets the towers (FIG. 10). The transfer collars 106 pass the load. Each collar has an inner peripheral configuration substantially similar to the external peripheral configuration of the tube adjacent to the tower.

As can best be seen in FIG. 11, the collars 106 within the towers 104 also accommodate expansion joints between the individual panels 34. A set of rollers 112 is located intermediate each collar 106 and the outer facing sheets 44 of the conduits. Other low friction means may be employed, such as a fluid film or a coated surface. As the sections of the tube expand and contract, the length differential is taken up by the motion of the connector panel which slides within the panels of the tube 20. The expansion and contraction of the roadway panel is accommodated for by an expansion dam as in the case of the pier bridge.

The cellular bridge tube 20 is attached to the hanger cables 102 of the suspended bridge structure by means of a set of hanger brackets 114 (see FIG. 12). Each one of the hanger brackets 114 is affixed to the outer portion of a vertical side of one of the conduits. Mechanical fasteners 116, such as rivets or the like, secure the hanger brackets 1 14 to the vertical surfaces. A transfer bolt 118 connects the hanger cable 102 to the upper extremity of the hanger bracket 114. The hanger brackets 114 are distributed along the entire span of the cellular bridge tube 20.

The catenaries may be eliminated in certain applications, and the hanger cables 102 may be employed directly between the top of the towers 104 and the hanger brackets 114 to provide direct cable support. Other variations are within the knowledge of those skilled in the art.

Referring now to FIG. 13, there is shown a variety of unsupported bridge span. This variety of bridge is often employed to span a relatively large distance. The bridge is composed of a cluster of conduits acting in conjunction with a space framework, generally labeled 120. In this arrangement, the cellular bridge tube forms the top or a compressive boom 122 of the bridge. A tension boom 124 is supported from the compressive boom 122 by means of the space framework. A number of compressive struts 126 are disposed between the compressive boom 122 and the tension boom 124. The compressive struts 126 are provided with a set of stabilizing cross members 128. A set of stabilizer cables 130 is disposed between the top and the bottom of each compressive strut 126, and each cable is connected to the corresponding stabilizing cross member 128.

Each of the stabilizing cross members 128 also serves as an expander to spread the stabilizer cables 130. Diagonal ties 132 run from the points where the compressive struts 126 connect with the compressive boom 122 to the tension boom 124. The hexagonal cellular conduits 22 are each provided with a roadway panel 54 having a road surface 32 over which vehicles may travel. An upper surfacing layer 134 may be applied over all of the hexagonal cellular conduits 22 to provide a smooth upper surface and protect the outer facing sheets 44 of the hexagonal cellular conduits 22. This forms another variety of enclosed cellular bridge tube 20.

In all cases, it is to be understood that the above described arrangements, in particular the materials to be used as core structures and facing sheets and the particular application to bridge construction, are merely illustrative of a particular embodiment to the many possible applications of the principle of the invention. Numerous and varied other arrangements in accordance with these principles may readily be devised by those skilled in the art without departing from the spirit and scope of the invention.

What is claimed is:

l. A cellular building structure comprising a multiplicity of hexagonal cells secured to one another in a honeycomb arrangement, a pair of bridge towers, a transfer collar disposed within and extending through each said bridge tower and supported by said tower for transmitting load from one side of the tower to the other, said cellular building structure being disposed within and extending through said transfer collar, and a multiplicity of cables supported by said bridge towers to support the length of said cellular building structure.

2. A cellular building structure according to claim 1 wherein all of said cells have substantially the same cross-sectional area and wherein the cross-section of each cell forms a regular equilateral hexagon.

3. A cellular building structure according to claim 1 which further comprises roadway means within each of said cells for dividing the cell into a pentagon and a triangle and wherein said roadway means is substantially horizontal.

4. A cellular building structure according to claim 1 wherein each of said cables is affixed to the outer surface of one of the hexagonal cells of said cellular building structure.

5. A cellular building structure comprising a multiplicity of hexagonal cells secured to one another in a honeycomb arrangement, at least one bridge tower, a transfer collar disposed within and extending through said bridge tower, said cellular building structure being disposed within and extending through said transfer collar, a multi licity of cables disposed between the uppermost pom on said bridge tower and said cellular building structure to support the length of said cellular building structure, a plurality of expansion joints, one for each of said hexagonal cells, positioned within said transfer collar, said transfer collar having an inner periphery substantially similar to the outer periphery of said cellular building structure, and a low friction means disposed intermediate said inner surface of said transfer collar and said outer periphery of said cellular building structure.

6. A cellular building structure according to claim 5 wherein said low friction means comprises a set of rollers capable of motion in a direction parallel to the length of the cellular building structure.

7. A cellular building structure according to claim 5 wherein said low friction means comprises a fluid film having a low coefiicient of friction.

8. A cellular building structure comprising a multiplicity of conduits, each of said conduits having a cross section substantially equal to an equilateral hexagon, a road surface disposed within each of said conduits to divide the conduits cross section into a pentagon and a triangle, said road surface being substantially horizontal, a tension boom disposed parallel to and below said cellular building structure, and a multiplicity of compressive struts interconnecting said structure and said tension boom.

Claims

1. A cellular building structure comprising a multiplicity of hexagonal cells secured to one another in a honeycomb arrangement, a pair of bridge towers, a transfer collar disposed within and extending through each said bridge tower and supported by said tower for transmitting load from one side of the tower to the other, said cellular building structure being disposed within and extending through said transfer collar, and a multiplicity of cables supported by said bridge towers to support the length of said cellular building structure.

5. A cellular building structure comprising a multiplicity of hexagonal cells secured to one another in a honeycomb arrangement, at least one bridge tower, a transfer collar disposed within and extending through said bridge tower, said cellular building structure being disposed within and extending through said transfer collar, a multiplicity of cables disposed between the uppermost point on said bridge tower and said cellular building structure to support the length of said cellular building structure, a plurality of expansion joints, one for each of said hexagonal cells, positioned within said transfer collar, said transfer collar having an inner periphery substantially similar to the outer periphery of said cellular building structure, and a low friction means disposed intermediate said inner surface of said transfer collar and said outer periphery of said cellular building structure.

7. A cellular building structure according to claim 5 wherein said low friction means comprises a fluid film having a low coefficient of friction.

8. A cellular building structure comprising a multiplicity of conduits, each of said conduits having a cross section substantially equal to an equilateral hexagon, a road surface disposed within each of said conduits to divide the conduit''s cross section into a pentagon and a triangle, said road surface being substantially horizontal, a tension boom disposed parallel to and below said cellular building structure, and a multiplicity of compressive struts interconnecting said structure and said tension boom.