Modular Reinforced Structural Beam and Connecting Member System

Abstract

A modular reinforced structural beam and connecting member system that includes at least one composite beam having two oppositely oriented triangular closed head portions and a transversally extending web interposed between said two closed head portions, each of said beams consisting of two separate members arranged such that corresponding head portions of said two members are nested one within the other and adjacent elements of the two members are in mutual stabilizing contact. A plurality of connecting members are connected to, and are in force transmitting contact with, one of the composite beams and another structural element.

Description

FIELD OF THE INVENTION

The present invention relates to the field of structural beams. More particularly, the invention relates to a modular reinforced structural beam system comprising connecting members, which is based on a novel lightweight beam having triangular head portions.

BACKGROUND OF THE INVENTION

Various types of structural beams are used in commercial and residential construction, including fabricated wooden girders, laminated wooden beams, reinforced concrete beams, and steel beams. Steel is the most commonly used material for beams, and such beams are configured by an I-section, H-section, C-section, Z-section and channel section. The various configurations of structural steel beams are most commonly manufactured by hot or cold rolling processes, and generally result in a relatively heavy beam for a given load bearing capacity.

I-beams are the most commonly used type of structural beam for constructing steel frames due to their relatively high load bearing capacity and moment of inertia. Such beams have a web and a pair of flanges perpendicular to, and in opposite edges of, the web such that the beams may be employed individually or in conjunction with a plurality of beams, and generally with a plurality of elements adapted to connect two or more beams, so as to safely support substantial static loads applied thereon. An assembly constructed from at least one beam or post, and generally from a plurality of beams or posts, and from a plurality of connecting elements will be referred herein as a “beam system”.

I-beams are formed by a hot rolling process following the casting of molten iron in a billet. Most I-beams that are delivered to a construction site have standard dimensions, e.g. a length of 6 or 12 m, and undergo additional construction processes, so that they will be customized to the architectural and engineering specifications of the given construction project, including cutting and welding one or more webs or one or more flanges to achieve a beam of desired dimensions, welding a connecting element to the beam, smoothing welded junction points, painting and galvanizing the beam or beam system, and assembling the beam or beam system in the frame structure. These additional construction processes are time consuming and costly.

It would be desirable, and that is the intent of this invention, to reduce the production and assembly costs of a beam system without compromising its structural properties.

Numerous structural beams fabricated from sheet steel, which require less steel than I-beams while providing the same load bearing capacity, are known in the prior art. For example, U.S. Pat. No. 991,603 issued to Brooks and U.S. Pat. No. 3,698,224 issued to Dunn et al disclose a metallic pseudo-I beam formed of a single piece of material which is bent to form hollow flanges at the top and bottom. U.S. Pat. No. 5,553,437 issued to the same inventor of the present invention discloses a pseudo-I beam made of two opposite oriented and interleaved members having a triangular head portion, a web portion, a web flange, and tail flange. The triangular shape of the head flange provides improved lateral stability with respect to conventional I-beams due to its biaxial symmetry.

Such prior art lightweight structural beams with triangular head portions are not readily formable by an automatic process. Firstly, the beams are produced by a cold rolling process during which sheet metal is passed through a plurality of pairs of rollers below its recrystallization temperature, annealed and bent to the desired shape. After two apices of the triangular are shaped, the fed metal sheet cannot be suitably supported to form the third apex due to the inaccessibility thereof. Also, the desired length of a structural beam is often 15 m, and the required thickness of the sheet metal needed for the fabrication of a structurally strong beam with triangular head portions is on the order of 8 mm, a thickness much greater than that which most commercial cold rollers can handle.

Butler Manufacturing Company, USA manufactures modular beam systems, as described in http://www.butlermfg.com/building_systems/structural.asp. These beam systems employ various components such as solid-web primary I-beam frames without triangular head portions, prepunched open-web truss purlins, which are secondary structural members, and rod bracing. In these systems, the beam system components are galvanized after the components are fabricated, and are welded together. Consequently the cost of manufacturing and assembly are relatively high. Furthermore, connecting elements are welded to the flange and not to the web portion. Stress is therefore concentrated on the flange, causing the components to be even more massive and costly.

It is an object of the present invention to provide a modular beam system based on a beam having a triangular head portion.

It is an additional object of the present invention to provide a modular beam system configured such that all of its components are assembled without need of welding.

It is an additional object of the present invention to provide a modular beam system provided with connecting elements that are attached to the web portion of a beam.

It is an additional object of the present invention to provide a beam having the same load bearing capacity as an I-beam, yet which is made of sheet metal having a thickness of no greater than 4 mm.

It is yet an additional object of the present invention to provide a method for producing a structural beam with a triangular head portion from galvanized sheet metal.

It is yet an additional object of the present invention to provide a method for producing a structural beam with a triangular head portion which is quicker and more economical than prior art structural beam producing methods.

It is yet an additional object of the present invention to provide a method for assembling a beam system which is quicker and more economical than prior art beam system assembly methods.

Other objects and advantages of the invention will become apparent as the description proceeds.

SUMMARY OF THE INVENTION

The present invention provides a modular reinforced structural beam and connecting member system, comprising at least one composite beam having two oppositely oriented triangular closed head portions and a transversally extending web interposed between said two closed head portions, each of said beams consisting of two separate members arranged such that corresponding head portions of said two members are nested one within the other and adjacent elements of said two members are in mutual stabilizing contact; and a plurality of connecting members, at least two of said connecting members being connected to, and in force transmitting contact with, one of said composite beams and another structural element.

As referred to herein, a “beam” is a rigid elongated structural member, which is supported at each end and is disposed at any convenient orientation, including a horizontal orientation, a vertical orientation when serving as a post, and an oblique orientation when serving as a ridge beam. A “transversal” direction means along the length of the beam. A “longitudinal” direction means the direction between the two triangular head portions of a beam. A “lateral” direction means the direction between the two web portions of the beam.

A connecting member, which is generally of relatively thick sheet metal, is connected to a composite beam by any suitable means, such as by cold fasteners and by welding, and at a region of the beam which requires reinforcement according to engineering considerations.

Each member of the composite beam comprises a first head portion, a second head portion, and a longitudinally disposed web portion interposed between said first head portion and second head portion, said first and second head portions being configured with a corresponding essentially laterally disposed flange, an oblique element extending from a first lateral end of said flange to said web portion, and an oblique lip extending from a first lateral end of said flange and having a length considerably shorter than that of said oblique element.

A first side of a triangular closed head portion comprises the two flanges of the two composite beam members, respectively, and second and third sides thereof comprise an oblique element of one of the composite beam members and a lip of the other composite beam member. With respect to the second and third sides of a closed head portion, the angular spacing between the oblique element and its corresponding flange is essentially equal to the angular spacing between the lip element and its corresponding flange.

Apices of the head portion of a first member are stiffened by the head portion of a second member in which said first member head portion is nested.

In a preferred embodiment, adjacent sides of a triangular closed head portion are angularly spaced by an angle of 60 degrees.

In a preferred embodiment, each beam member is cold rolled. A composite beam is therefore automatically produced by feeding galvanized sheet metal through a plurality of cold rollers; punching apertures in said sheet metal, to facilitate connection to a connecting member or to air conditioning equipment, or through which pass electric cables; bending said sheet metal to a desired shape and with desired dimensions to form a first member; repeating these steps to form a second member; and displacing at least said second member such that corresponding head portions of said first and second members are nested one within the other, that adjacent elements of said first and second members are in mutual stabilizing contact, and that corresponding transversal edges of said first and second members are aligned.

In one aspect, the beam system further comprises means for joining corresponding flanges of the first and second beam members, such as cold fasteners for preventing relative transversal displacement of one of said beam members.

In one aspect, the beam system further comprises means for joining corresponding web portions of the first and second beam members, such as cold fasteners.

In one aspect, the flange of the first head portion of a beam member has a longer lateral dimension than the flange of the second flange portion.

In one aspect, first and second members are identical, said second member being in opposite orientation than said first member such that the first head portion of the second member is nested within the second head portion of the first member and the first head portion of the first member is nested within the second head portion of the second member.

In one aspect, the flange of the first head portion of a beam member has the same lateral dimension as the flange of the second flange portion. The first head portion of the second member is nested within the first head portion of the first member and the second head portion of the second member is nested within the second head portion of the first member.

In one aspect, the first head portion of the second member is nested within the first head portion of the first member and the second head portion of the second member is nested within the second head portion of the first member.

In one aspect, a junction between the oblique element and web portion of the first member and a junction between the oblique element and web portion of the second member are coplanar on a plane parallel to the corresponding flanges.

In one aspect, a connecting member is connected to a composite beam by means of cold fasteners engageable with corresponding aligned apertures bored in the connecting member and beam. Thus a connecting member may be connected to a beam without need of welding, and construction workers assembling a beam system do not require specialized training.

Each beam and connecting member may be fabricated from materials selected from the group of steel, metals, alloys, plastic materials, and composite materials.

The connecting member is preferably an off the shelf product which is connected in situ by means of cold fasteners.

In one aspect, the beam system comprises more than one element which are welded together.

In one aspect, a connecting member is connected to a composite beam by means of cold fasteners and a reaction plate insert attached internally to said beam.

In one aspect, a connecting member is configured as a sleeve having selected transversal, longitudinal and lateral dimensions, and is adapted to completely surround and to be in mutually stabilizing contact with a portion of a composite beam perimeter having said selected dimensions.

In one aspect, a sleeve is connected to two coplanar beams, thereby producing a relatively lightweight combined beam of increased transversal length that can span considerably longer distances and require less bracing than beams of prior art beam systems. If the transversal length of the combined beam is different than the in situ clearance, a construction worker performs a telescopic adjustment of the combined beam by sliding one or two beams of the combined beam relative to the sleeve and connecting aligned apertures of the sleeve and a corresponding beam. If the apertures are not aligned, additional apertures are bored and then cold fasteners are engaged with the aligned apertures.

In one aspect, the sleeve comprises two cold rolled elements that are welded together.

In one aspect, the sleeve comprises a single element, two adjacent edges of which are welded together.

In one aspect, the sleeve comprises two adjacent half sleeves that are connected to the two lateral sides, respectively, of a beam.

In one aspect, the connecting member is configured with only one web.

In one aspect, the web of the connecting member is substantially shorter than the web of the beam to which the connecting member is attached.

In one aspect, the connecting member comprises a plate in force transmitting contact with a web or flange of a beam.

In one aspect, the connecting member comprises two angularly spaced plates and an element extending between, and oblique with respect to, said two plates.

In one aspect, the connecting member further comprises at least one rib.

In one aspect, the connecting member is configured as a moment connection.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a perspective view of two members of a composite beam as they are being nested one within the other;

FIG. 2 is a side view of a composite beam in which the two beam members are in an alternately nested arrangement;

FIG. 3 is a perspective view of a composite beam, showing apertures that are bored in the web and flanges thereof;

FIG. 4 is a side view of a composite beam, according to another embodiment of the invention;

FIG. 5 is a side view of a composite beam, according to another embodiment of the invention;

FIG. 6 is a side view of a connecting member configured as a sleeve;

FIG. 7 is a side view of the connecting member of FIG. 6 in surrounding and mutually stabilizing contact with the beam of FIG. 2;

FIG. 8 is a side view of a connecting member having one web;

FIG. 9 is a side view of a connecting member having one web which is considerably shorter than the web of a beam to which it is connected;

FIG. 10 is a perspective view of a connecting member which is adapted to connect two transversally spaced beams;

FIG. 11 is a perspective view of a connecting member adapted to connect two longitudinally spaced beams;

FIG. 12 is a perspective view of a connecting member adapted to connect a beam to a planar structural element;

FIG. 13 is a perspective view of a connecting member configured as a moment connection;

FIG. 14A is a perspective view of another embodiment of a connecting member which is configured as a moment connection;

FIG. 14B is a vertical cross-sectional view of a reaction plate insert, cut about plane A-A of FIG. 14A;

FIG. 14C is a horizontal cross-sectional view of a corner sleeve, cut about plane B-B of FIG. 14A and showing a top view of the reaction plate insert of FIG. 14B;

FIG. 15 is a perspective view of a connecting member which is adapted to connect a beam to a girder;

FIG. 16 is a perspective view of a connecting member which is adapted to be a ridge connection;

FIG. 17 is a perspective view of a connecting member which is adapted to connect a post to a beam in side by side relation;

FIG. 18 is a perspective view of a connecting member which is adapted to connect a post to a vertically spaced beam;

FIG. 19 is a perspective view of a connecting member which is adapted to connect two mutually perpendicular beams of different longitudinal dimensions;

FIGS. 20 and 21 illustrate connecting members, respectively, which are used as cable connectors;

FIGS. 22-26 illustrate connecting members, respectively, that are adapted for connection to a corresponding purlin;

FIG. 27 is a side view of a connecting member which is configured as a plate;

FIG. 28 is a top view of another embodiment of a connecting member;

FIG. 29 is a side view of a beam to which is connected two connecting members of FIG. 27;

FIG. 30A is a side view of a composite beam to which is connected a reaction plate insert;

FIG. 30B is a front view of the beam of FIG. 30A;

FIG. 30C is a front view of two beams which are connected by the connecting member of FIG. 10;

FIG. 31 is a front view of a beam system provided with a moment and ridge connection;

FIG. 32 is a front view of a beam system adapted for connecting two pillar attached beams;

FIG. 33 is a perspective view of a beam system which employs a plurality of beams and connecting members, similar to the layout a prior art beam system;

FIG. 34 is a perspective view of another beam system which employs a plurality of beams and connecting members, showing, with respect to the layout of FIG. 33, an increased span between posts that can be realized with the use of the beams and connecting members of the present invention;

FIG. 35 is a horizontal cross sectional view of a connecting member which is adapted to connect a beam to a wall;

FIG. 36A is a side view of a connecting member which comprises two identical and differently oriented parts that are welded together to define a sleeve having two triangular head portions; and

FIG. 36B is a side view of one of the parts of FIG. 36A.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention is a novel lightweight structural beam having two triangularly shaped head portions which provide an increased lateral stability and strength to weight ratio with respect to conventional I-beams. While some prior art beams have been configured with triangularly shaped head portions produced by a cold rolling process, these head portions are closed triangles and the third side thereof cannot be quickly and automatically shaped due to its inaccessibility and the inability of rollers to support the fed sheet metal as it is bent to form a closed triangle. In contrast, the beam of the present invention is a composite beam made of two separate and oppositely oriented members arranged such that corresponding head portions of the two members are nested one within the other. Each head portion is an incomplete triangle, so that the lip, i.e. an extremity, of a member is sufficiently accessible to rollers to allow the desired configuration of the member to be shaped. When a head portion of one member is nested within the corresponding head portion of the other member, a closed triangle having two-layered and therefore stiffened apices is produced. Cold fasteners are used to connect the webs of the two members and to connect the beam to a connecting member, as will be described hereinafter. No welding is needed, and therefore the production of such a beam and the assembly of a beam system employing one or more beams of the present invention are quicker and more economical than, and have substantially the same load bearing capacity than, that of the prior art.

FIG. 1 illustrates a perspective view of two transversally extending members of a composite beam as they are being nested one within the other. The beam, which is designated by numeral 10, comprises two identical oppositely oriented members 5 and 15. The following description relates to member 5, and it will be appreciated that member 15 is similarly configured.

Member 5 has a first head portion 2, a second head portion 12, and a longitudinally disposed web portion 7 interposed between first head portion 2 and second head portion 12. First head portion 2 has an essentially laterally disposed flange 6, i.e. perpendicular to the longitudinally disposed web portion 7, oblique element 3 extending from transversally extending first head portion junction 4 to junction 8 at one lateral end of flange 6, and lip 13 extending obliquely from junction 11 of flange 6 at the other transversal end thereof. Lip 13 is directed to junction 4; however its length is considerably shorter than oblique element 3. Second head portion 12 has an essentially laterally disposed flange 16 having a lateral dimension longer than flange 6 of first head portion 2, oblique element 23 extending from transversally extending second head portion junction 14 to junction 18 at one lateral end of flange 16, and lip 27 extending obliquely from junction 26 of flange 16 at the other lateral end thereof. Lip 27 is directed to junction 14; however its length is considerably shorter than oblique element 23.

The angle between lip 13 and flange 6 of first head portion 2 is essentially equal to the angle between oblique element 23 and flange 16 of second head portion 12. The angle between lip 27 and flange 16 of second head portion 12 is essentially equal to the angle between oblique element 3 and flange 6 of first head portion 2. The longitudinal dimension from junction 14 to flange 16 of second head portion 12 is substantially equal to the sum of the longitudinal dimension from junction 4 to flange 6 of first head portion 2 and of the thickness of flange 6. Thus when first head portion 2 of member 5 is nested within second head portion 12 of member 15, and when first head portion 2 of member 15 is nested within second head portion 12 of member 5 (hereinafter referred to as “the first and second head portions are in an alternately nested arrangement”), corresponding elements of members 5 and 15 are in mutual stabilizing contact, meaning that an element of member 5 is adapted to physically contact and to stabilize a corresponding element of member 15, or vice versa, when an external force is applied to beam 10 which causes insignificant relative displacement of member 5 with respect to member 15. While two elements in mutual stabilizing contact may not necessarily be in mutual physical contact as the first and second head portions are in an alternately nested arrangement, said two elements may be in physical contact during the application of an external force. Thus the mutual stabilizing contact will prevent further displacement of the displaced element. As illustrated, each web portion 7 of members 5 and 15, and each corresponding pair of flanges 6 and 16, of oblique element 3 and lip 27, and of oblique element 23 and lip 13 are in mutual stabilizing contact. Since beam provides mutual stabilizing contact between corresponding elements of members 5 and 15, the thickness of the sheet steel may be only 4 mm, requiring a relative simple cold rolling machine, yet provides the structural strength of 8-mm thick sheet steel.

Composite beam 10 also promotes stiffened apices when the first and second head portions are in an alternately nested arrangement. Although the first and second head portions are incomplete triangles, an essentially closed triangle is formed when they are in a nested arrangement. Thus, with reference to the bottom composite head portion, a closed triangle is defined by a two-layered base consisting of flanges 6 and 16, a first side which is oblique element 23 of member 5, and a second side which is oblique element 3 of member 15. As the first head portion of member 15 is nested within the second head portion of member 5, the vertices, or rounded portions connecting two adjacent elements in the vicinity of a junction, of first head portion of member 15 are stiffened by the vertices of the second head portion of member 5, which are in mutual stabilizing contact therewith. The closed triangle of a composite head portion is preferably an equilateral triangle, although a closed triangle having other combinations of angles is also suitable.

Another advantage provided by the formation of a closed triangle by a composite head portion is that, due to the difference in dimensions of the first and second head portion elements, each pair of first head portion junction 4 and second head portion junction 14 are coplanar on a plane parallel to flanges 6 and 16. If a first head portion junction 4 and second head portion junction 14 were not coplanar on a plane parallel to flanges 6 and 16 in contradistinction to the present invention, regions of the two web portions 7 would not be in mutual stabilizing contact. For example, with reference to the bottom composite head portion, junction 14 of member 5 may be below junction 4 of member 15, causing the region of web portion 7 of member 5 below junction 4 of member 15 to be unsupported and therefore being susceptible to buckling when a sufficiently high force is applied. The closed-triangle configuration of the composite head portion of the present invention therefore increases the lateral stability of the beam, which is of much importance when exposed to high winds or earthquakes.

FIG. 2 illustrates a side view of composite beam 10, which is oriented differently than in FIG. 1. Relative transversal displacement of members 5 and 15 is prevented by connecting a pair of flanges 6 and 16 of each of the top and bottom composite head portions by cold fasteners 41, e.g. screws, bolts, nuts, and rivets. Blind rivets are the preferable choice for flange fasteners due to their inaccessibility within a beam head portion, after passing through the corresponding flanges. Cold fasteners 41 also enable the transmission of tensile and compressive forces, as well as moments, from one flange to another. It will be appreciated that two adjacent flanges may be connected to each other by any other suitable connection means such as spot welding and laser welding, although cold fasteners are preferable due to the ease in assembly. The two webs 7 of members 5 and 15, respectively, are connected to each other by cold fasteners 42, or any other suitable connection means, so that shear forces will able to be transmitted from one web to the other.

FIG. 3 illustrates a perspective view of composite beam 10, showing an exemplary location of apertures bored in beam 10, by which are attached connecting members, as will be described hereinafter, or cold fasteners to the beam. As shown, web apertures 32 are bored in web 7 in the vicinity of front and rear transversal edges 34 and 34 thereof. Flange apertures 36 are bored in upper and lower pairs of flanges 6 (FIG. 2) and 16 in the vicinity of front and rear transversal edges 38 and 39 thereof, although only the upper pair of flanges is illustrated for clarity. It will be appreciated that web apertures 32 and flange apertures 36 can be bored at other locations as well, depending on the type of connecting member attached to beam 10. The number of apertures that are bored at any given location depends on engineering considerations, such as the thickness of the sheet metal, the dimensions of the beam, and the stress concentration at said location.

It will be appreciated that a composite beam of the invention may be used not only as a beam when it is oriented such that the transversal direction is horizontal or oblique, but also as a post when it is oriented such that the transversal direction is vertical. It will be assumed that the following description applies to a beam having a horizontal transversal direction, but all other beam orientations are also applicable.

As members 5 and 15 are identical, as described in reference to FIG. 1, the two members may be fabricated in the same cold rolling process whereby first and second head portions 2 and 12 characterized by an incomplete triangle are formed from galvanized sheet metal. The production costs of welded hot-rolled I-beams are considerably more costly since, in addition to the time and cost involved in welding the various beam elements, the fabricated beam needs to be galvanized. Composite beam 10 is then produced by inverting one of the members. With respect to the orientation of FIG. 1, for example, member 15 has an upper second head portion 12 which is larger than its smaller first lower head portion 2, and member 5 has an upper first head portion 2 which is smaller than its lower second head portion 12. Member 15 is then slightly raised until its lower first head portion 2 is received in the lower second head portion 12 of member 5 and its upper second head portion 12 surrounds upper first head portion 2 of member 5. Member 15 is then slid transversally until front and rear transversal edges 38 and 39 (FIG. 3) of members 5 and 15 are aligned, so that members 5 and 15 will be in mutually stabilizing contact while in an alternately nested arrangement. The web and flange apertures may be bored after the two members are nested, or alternatively, during the cold rolling process, in accordance with given engineering considerations. All of the aforementioned steps needed to produce composite beam 10 may be performed automatically with computerized feeding and indexing equipment.

FIG. 4 illustrates a side view of a composite beam 40 in which the two members 44 and 54 are not identical, but rather the top and bottom head portions 46 and 48, respectively, of member 44 are identical and the top and bottom head portions 56 and 58, respectively, of member 54 are identical. The head portions of member 54 are smaller than those of member 44, and are in a nested arrangement that also promotes stiffened apices such that head portion 56 of member 54 is nested in head portion 46 of member 44, head portion 58 of member 54 is nested within head portion 48 of member 44, and corresponding elements of members 44 and 54 are in mutual stabilizing contact. The two members 44 and 54 are fabricated by two separate cold rolling processes, respectively, and then member 54 is slightly raised until its head portions 56 and 58 are received in head portions 46 and 48, respectively, of member 44. Member 54 is then displaced until it is transversally aligned with member 44.

FIG. 5 illustrates a side view of a composite beam 60 in which the two members 64 and 74 are not identical and have differently sized top and bottom head portions. Upper head portion 76 of member 74 is nested in upper head portion 66 of member 64, and lower head portion 78 of member 74 is nested within lower head portion 68 of member 64.

Since the two members of a composite beam of the present invention are in mutually stabilizing contact, the vertices of the top and bottom composite head portions are stiffened, and each pair of first and second head portion junctions are coplanar on a plane parallel to the corresponding flanges, the beam of the present invention requires less steel than beams of the prior art for the same span while providing the same load bearing capacity.

.Tables I-III below compare the beam of the present invention (referred to as “Invention”) to various prior art I-beams in terms of its weight and maximum deflection (referred to as “%”), for a given required moment of inertia (MOI).

TABLE I
15 meter span - 8 meters on center - Allowed Def. L/250 - required MOI
27204 cm4 - Dead Load 25 kg/m2. Live Load + wind 40 kg/m2.
						Japanese
	Invention					I-Beam
Beam	520 × 120 × 4	INP 400	HEB 320	HEA 340	IPE 450	400 × 150
Span	15 m	15 m	15 m	15 m	15 m	15 m
kg/meter	57	92.4	127	105	77.6	95.8
%	100	162	222	184	136	168

TABLE II
20 meter span - 4 meters on center - Allowed Def. L/250 - required MOI
32242 cm4 - Dead Load 25 kg/m2. Live Load + wind 40 kg/m2.
						Japanese
	Invention					I-Beam
Beam	550 ± 120 × 4	INP 425	HEB 340	HEA 360	IPE 450	400 × 175
Span	20 m	20 m	20 m	20 m	20 m	20 m
kg/meter	58.9	104	134	112	77.6	91.7
%	100	177	228	190	131.7	155.6

TABLE III
20 meter span - 8 meters on center - Allowed Def. L/250 - required MOI
64484 cm4 - Dead Load 25 kg/m2. Live Load + wind 40 kg/m2.
						Japanese
	Invention					I-Beam
Beam	730 ± 120 × 4	INP 500	HEB 450	HEA 500	IPE 550	600 × 190
Span	20 m	20 m	20 m	20 m	20 m	20 m
Kg/meter	70.1	141	171	155	106	169.4
%	100	201	244	221	151.2	241.6

As can be seen, the beam of the present invention has a significantly less weight, approximately 55% less, than that of prior art I-beams for the same span and required MOI. Also the maximum deflection for the beam of the present invention is significantly less than that of the present invention.

Heretofore, a beam has been subjected to high stress concentrations when connected by welding to other structural members such as C-shaped or Z-shaped purlins, which are adapted to support a roof support or a metal deck. Due to the concentrated loads, the beams need to be reinforced by e.g. ribs at each stress concentration. The reinforcing members have to be connected to the beam and to the purlin by welding, further increasing the costly, labor intensive and time consuming assembly process.

The beam system of the present invention significantly reduces the cost, labor and time needed to assemble a beam system by providing a prefabricated connecting member that is attachable to the beam by cold fasteners. The connecting member in turn is attached to another structural element, and is therefore adapted to transmit forces or moments from one structural element to another. Apertures, to which connecting members are attached, are bored in the sheet steel during the production of the composite beam, as illustrated in FIG. 3. The apertures may assume any convenient shape including circular, rectangular and oval apertures. Alternatively, the apertures may be bored in situ. The apertures may be bored in any convenient region of the sheet steel, whether to the flange or to the web, in accordance with engineering considerations. The beam system is therefore modular in the sense that the same beam can be used in many different applications, and may also be disassembled from a first connecting member and attached to a second connecting member. Another advantage of the beam system of the present invention is that a connecting member may be attached to a beam of an existing structure without any welding, in order to distribute the load applied by an assembly that is newly mounted onto the structure, e.g. an industrial air conditioner. With respect to prior art beam systems, in contrast, the structure needs to undergo renovations, including bracing and welding, in order to reduce the concentrated stress imposed by the newly mounted assembly.

FIG. 6 illustrates a side view of a connecting member, which is generally designated by numeral 80, according to one embodiment of the invention. Connecting member 80 is configured as a sleeve having a selected transversal length, and is adapted to completely surround and to be in mutually stabilizing contact with a portion of a composite beam perimeter having said selected transversal length. The sleeve may be formed by welding together two or more cold rolled elements, such as two symmetrical elements, or by welding together two adjacent edges of a single element. Alternatively, as illustrated by connecting member 80A of FIG. 15, a sleeve may be comprised of two adjacent half sleeves that are connected to the two lateral sides, respectively, of a beam.

As shown, connecting member 80 has upper triangular head portion 82, lower triangular head portion 84, and spaced, parallel web portions 86 and 87 longitudinally extending between upper head portion 82 and lower head portion 84. Head portion 82 has a flange 91, and two oblique elements 93 and 94 extending from flange 91 to web portions 86 and 87, respectively. Similarly, head portion 84 has a flange 95, and two oblique elements 97 and 98 extending from flange 95 to web portions 86 and 87, respectively. The webs and flanges are bored with apertures at predetermined locations, to allow connecting element 80 to be attached to a composite beam by cold fasteners. Connecting member 80 is formed with suitable dimensions and with a suitable configuration which facilitate mutually stabilizing contact with corresponding externally facing elements of a composite beam around which connecting member 80 surrounds.

In FIG. 7, connecting member 80 is shown to surround, and to be in mutually stabilizing contact with, members 5 and 15 of composite beam 10. With further reference to FIGS. 1, 2 and 6, connecting member 80 is transversally displaced along beam 10 until it is disposed at a selected region thereof which is anticipated to be subjected to a concentrated load. After cold fasteners 71 are attached to the corresponding flanges of beam 10 and connecting member 80 via the corresponding aligned flange apertures, and cold fasteners 72 are attached to the corresponding webs of beam 10 and connecting member 80 via the corresponding aligned web apertures, elements of the beam and connecting member are in force transmitting and mutually stabilizing contact. For example, flange 91 of connecting member 80 contacts flange 16 of member 5, and oblique element 98 of connecting member 80 contacts lip 27 of member 15.

Flange fasteners 71 are generally blind rivets, and web fasteners 72 are generally pairs of bolts passing through the aligned web apertures and threadedly engaged with corresponding nuts. Flange fasteners 71 may also be bolts that are threadedly engageable with a reaction plate insert 176 (FIG. 14B), to provide a stronger attachment force. Reaction plate insert 176 consists of a short plate 172 and a long plate 174 which are welded together, e.g. in such a way that edges 176 and 177 thereof, respectively, at one transversal end are coplanar. Insert 176 is attached to a corresponding pair of beam flanges by means of fasteners passing through internally threaded bores 171 formed within plates 172 and 174. A flange of the selected connecting member is therefore attachable to long plate 174, which is spaced from the beam flange, by means of flange fasteners 71, which are adapted to engage with internally threaded bores 179 formed in long plate 179.

In FIG. 8, connecting member 100 is configured with only one web 104, and is therefore adapted to be in force transmitting contact with only lateral side of a composite beam. Connecting member 100 also has oblique elements 101 and 103 extending in the same lateral direction from the upper and lower ends, respectively, of web 104, and upper and lower flanges 107 and 109 extending from oblique elements 101 and 103, respectively, via vertices 111 and 112, respectively. Flanges 107 and 109 have substantially the same lateral dimension as that of the flanges of the beam to which connecting member 100 is attached. However, flanges 107 and 109 may be configured with a lateral dimension significantly less than that of the corresponding flanges of the composite beam, depending on engineering considerations. Thus connecting member 100 is adapted to be in force transmitting contact with the two head portions of a beam.

In FIG. 9, connecting member 110 is adapted to be in force transmitting contact with an upper portion of a beam, at one lateral end thereof. Connecting member 110 has a web portion 114 substantially shorter than the web of the beam to which the connecting member is attached. Oblique element 101 extends from the upper end of web portion 114, and flange 107 extends from vertex 111 adjoining oblique element 101.

As shown in FIG. 27, a connecting member 45 may be a plate, e.g. which may be in force transmitting contact with a web or flange of a beam. FIG. 29 illustrates a beam 50 comprising plates 45A and 45B, which are connected to the web of members 5 and 15, respectively. Such a beam may be produced with three or four members, i.e. members 5 and 15, and plates 45A and/or 45B. Alternately, the beam may be produced without the plates, and the plate-like connecting members may be connected to the web in situ.

With reference to FIG. 28, a connecting member 55 shown in top view may be in partial force transmitting contact with two structural elements. Connecting member 55 comprises two plates 57 and 59, which are angularly spaced, e.g. in a mutual perpendicular disposition as shown, and element 61 extending between, and oblique with respect to, plates 57 and 59. Plate 57 and 59 are therefore adapted to be connected to two different angularly spaced structural elements.

FIGS. 36A-B illustrate a connecting member 420 which comprises two identical and differently oriented parts 425 and 428, which are welded together to define a sleeve having two triangular head portions 431 and 432, in order to be in mutually stabilizing contact with a composite beam. With respect to part 425, part 428 is inverted and flipped over.

As shown in the orientation of FIG. 36B, part 428 is formed with a web portion 421, upper and lower flange portions 426 and 427, respectively, an oblique element 423 extending from lateral end 429 of flange portion 427 to lower longitudinal end 422 of web portion 421, oblique element 434 extending from upper longitudinal end 432 of web portion 421 to lateral end 439 of flange 426 and substantially symmetrical to oblique element 423, and oblique lip 438 extending from lateral end 442 of flange 427 and disposed at the same angle with respect to flange 427 as that of oblique element 434 with respect to flange 426. The length of oblique elements 434 and 438, one of which being from part 425 and the other being from part 428, are selected so that they will overlap when part 428 is in an inverted and flipped orientation with respect to part 425, to allow for the application of weld spots 435A-B between a pair of oblique elements 434 and 438, as shown in FIG. 36A. Each pair of flanges 426 and 427 will be in mutual force transmitting contact by means of flange fasteners, which will also engage apertures bored in the corresponding flanges of a composite beam connected to connecting member 420.

FIGS. 10-26 and 35 illustrate exemplary connecting members that can be attached by cold fasteners to a beam of the present invention. These connecting members, which are generally off the shelf assemblies, can be in force transmitting contact with two lateral ends of the beam, as shown in FIG. 6, or with only one lateral end of the beam, as shown in FIG. 8. A connecting member will be referred to as being “connected” to a composite beam when it is shaped similarly to a portion of said beam, brought in force transmitting contact with said beam, and attached to said beam by means of cold fasteners and/or welding. It will be appreciated that any of the connecting members can be configured differently than the illustrated members, such as by different shapes, orientations, dimensions, thickness, number of fasteners, and location of fasteners.

FIG. 10 illustrates connecting member 120, which is used to connect two beams 122A and 122B having identical profiles, i.e. the same longitudinal and lateral dimensions. Due to size and weight limitation of transportation equipment, a beam having a considerably long transversal length, e.g. 20 m, usually cannot be economically transported. Two shorter beams can therefore be transported to a construction site, and then quickly coupled together by means of connecting member 120 and cold fasteners 71 and 72 in situ, so that the transversal length of the combined beam can be increased without need of welding, as has been practiced heretofore in the prior art. Flange fasteners 71 connect upper and lower flanges 122 and 124 of the connecting member to corresponding upper and lower flanges, respectively, of the beam. Web fasteners 72 connect one or more webs 126 of the connecting member to corresponding webs of the beam to produce a shear connection. Four columns of cold fasteners 71 and 72 are employed, two columns for attachment to aligned apertures of beam 122A and connecting member 120, and two columns for attachment to aligned apertures of beam 122B and connecting member 120.

If for some reason the apertures of a beam and connecting member 120 are not aligned, the modularity of the beam system of the invention affords a construction worker sufficient flexibility to reposition the beam or connecting member in such a way to ensure that the connecting member and beam will be connected. For example, the beam can be transversally displaced in telescopic fashion until its apertures will be aligned with other apertures of connecting member 120. Alternatively, the apertures of connecting member 120 may be suitably formed, such as by having an elliptical shape, so that when the beam is slightly displaced transversally, a portion of a connecting member aperture will be sufficiently exposed to permit engagement with a cold fastener passing through a corresponding beam aperture even though another portion of said connecting member aperture is covered by the beam periphery. If the beam apertures cannot be aligned with the connecting member apertures, additional apertures may be bored in the beam periphery. It will be appreciated that the other connecting members that will be described hereinafter can also be repositioned in situ in order to quickly and effortlessly connect a beam and selected connecting member.

Alternatively, as shown in FIGS. 30A-C, connecting member 120 can be used to connect beams 122A and 122B by means of upper and lower reaction plate inserts 127 and 128, respectively. FIG. 30A illustrates a side view connecting member 120 which is connected to beam 122A by means of inserts 127 and 128. Prior to assembly, inserts 127 and 128 are attached to the flanges of beam 122A by flange fasteners 71, as shown in FIG. 30B. Connecting member 120 is then attached to beam 122A by means of inserts 127 and 128 and elongated flange fasteners 181, as shown in FIG. 30C, and by web fasteners (not shown) that pass through an aperture 129 bored in the web of connecting member 120 and an aperture 32 bored in the web of beam 122A. Beam 122B is then placed in close proximity to beam 122A after being inserted within connecting beam 120, after which connecting member 120 is attached to inserts 127 and 128 and to the flanges of beam 122B by elongated fasteners 181 and by web fasteners. Beams 122A and 122B may be placed in close proximity before connecting member 120 is slid over the two beams and connected.

FIG. 11 illustrates connecting member 130, which is used to connect four beams-two pairs of adjacent beams are transversally connected and two pairs of adjacent beams are longitudinally connected by means of connecting member 130. Connecting member 130 comprises connecting member 120 of FIG. 10 and two plates 132 and 134 connected to upper and lower flanges 122 and 124, respectively, of connecting member 120. Flange fasteners 71 are used to connect upper and lower plates 132 and 134, upper and lower flanges 122 and 124 of connecting member 120, and upper and lower flanges of two transversally connected beams, respectively. Two pairs of adjacent beams are transversally connected as described hereinabove with respect to connecting member 120. Two pairs of adjacent beams are longitudinally connected by connecting a lower plate 134 of an upper connecting member 130 with an upper plate 132 of a lower connecting member 130 by means of cold fasteners passing through aligned apertures 137 of the plates which are laterally spaced from flange fasteners 71.

FIG. 12 illustrates connecting member 140 by which a beam, e.g. a post, is attached to a structural element 148 such as a foundation or a pillar. Connecting member 140 comprises a sleeve-like connecting member 80 connected to a transversal end of beam 145. The longitudinal free edges 142 of connecting member 80, i.e. the edges extending away from beam 145, are welded to structural end plate 146 substantially perpendicular to web 7 of beam 145. Plate 146 is then placed in abutting relation with structural element 148 and attached thereto by connecting means 149 with sufficient structural strength to withstand all anticipated forces and moments to which beam 145 will be subjected. It will be appreciated that any beam system of the present invention will invariably employ a connecting member 140 for attachment to a structural element.

FIG. 13 illustrates connecting member 150 for connecting vertical beam 154 and horizontal beam 158 by a moment connection. Connecting member 150 comprises two corner sleeves 152 and 153 connected to beams 154 and 158, respectively, by flange fasteners 71, e.g. blind rivets, and web fasteners 72, e.g. bolts and corresponding nuts. Corner sleeves 152 and 153 have two spaced trapezoidal webs 159 which are configured such that the distal edge 161 thereof, i.e. the edge distant from the corner, is substantially longitudinally disposed, and the proximal edge 163 thereof, i.e. the edge closest to the corner, is oblique with respect to distal edge 161, e.g. at an angle of approximately 45 degrees. Corner sleeves 152 and 153 also have a long flange 164 and a short flange 166 extending from distal edge 161 to proximal edge 163. Oblique end plates 167 and 168 are placed in abutment with, and welded to, proximal edge 163 and flanges 164 and 166 of corner sleeves 152 and 153, respectively. The two oblique end plates 167 and 168 are then bolted together. The volume within a corner sleeve from its proximal edge to the proximal transversal edge of the corresponding beam in force transmitting contact therewith is hollow.

FIGS. 14A-C illustrate a connecting member 170 provided with a reaction plate insert 176, for connecting vertical beam 154 and horizontal beam 158 by a moment connection. Connecting member 170, which is configured similarly to that of connecting member 150 (FIG. 13), comprises two corner sleeves 182 and 183 connected to beams 154 and 158, respectively, by elongated flange fasteners 181 engageable with corresponding internally threaded bores 171 and 179 of a reaction plate insert 176 and by web fasteners 72. Short plate 172 of insert 176 is attached to flanges 6 and 16 of a corresponding beam, which are adjacent to long flange 184 of connecting member 170. Long plate 174 of insert 176 extends proximally from the proximal edge of short plate 172, and allows a portion of flange 184 of connecting member 170 which is not in abutment with the flanges of the beam to be secured thereby. Thus connecting member 170 can withstand relatively high forces that are exposed thereto. Corner sleeves 182 and 183 have two spaced trapezoidal webs configured similarly to web 159 of FIG. 13, although of a longer transversal dimension.

FIG. 15 illustrates connecting member 190, which is adapted to connect beam 194 to girder 195, e.g. a perimeter beam or a ridge beam. Connecting member 190 comprises sleeve 80A connected to a transversal end of beam 194, sleeve 80B connected to an intermediate portion of girder 195 and substantially perpendicular to sleeve 80A, end plate 197 welded to, and extending laterally between, the two webs of sleeve 80A, and plate 198 welded to, and extending transversally from, the center of end plate 197 and of the adjacent web of sleeve 80B.

FIG. 16 illustrates connecting member 200, which is adapted to be a ridge connection, e.g. at an apex of a structure such as the top of a roof. Connecting member 200 comprises two end plates 201 and 202 which are bolted together, two symmetric sleeves 204 and 205 welded to plates 201 and 202, respectively, and two pairs of symmetric triangular ribs 207 and 208. Ribs 207 and 208, are generally, but not necessarily, oriented such that their bottom edges 217 and 218, respectively, are parallel to the underlying ground surface. The proximal transversal end of sleeves 204 and 205 are cut at a predetermined angle, and the proximal edges are then placed in abutting relation and welded to the corresponding end plate. Each rib 207 and 208, which is adapted to reinforce connecting member 200, is welded to a corresponding connecting member flange and to a corresponding end plate such that the short leg of the rib contacts the end plate and a long leg contacts the connecting member flange. Beams 212 and 214 are then inserted within, and connected to, sleeves 204 and 205, respectively. With the use of connecting member 200, the angle between beams 212 and 214 can be assured of being a predetermined value and the structural integrity of the ridge connection can be maintained.

With reference to FIG. 17, connecting member 220 is adapted to connect a post 225 to beam 228. Connecting member 220 comprises connecting member 140 of FIG. 12 which is provided with end plate 146, two connecting members 55 of FIG. 28, and a plurality of pre-welded ribs 229. Connecting member 140 is connected to a transversal end of beam 228, and each connecting member 55 is connected to a corresponding lateral end of post 225. At each lateral end of post 225, plate 59 is connected by cold fasteners to the web of post 225, element 61 abuts the corresponding oblique element in the head portion of post 225, and plate 57 is connected by cold fasteners to end plate 146 (see FIG. 28). A plurality of horizontally disposed ribs 229, e.g. three as shown, are welded to both plates 57 and 59.

FIG. 18 illustrates connecting member 230, which is also adapted to connect a post 225 to beam 228. While the post and beam connected by connecting member 220 of FIG. 17 are in side by side relation, connector 230 is configured to connect a post and beam which are vertically spaced. That is, connector 230 is identical to connector 220, although with a different orientation, and is provided with member 140 of FIG. 12, two connecting members 55 of FIG. 28, and a plurality of pre-welded ribs 229.

FIG. 19 illustrates connecting member 240, which is adapted to connect two mutually perpendicular beams 242 and 244 of different longitudinal dimensions. Connecting member 240 comprises single-web connecting member 100 of FIG. 8 and variably shaped planar element 245. Variably shaped element 245 has a rectangular portion 246 which is connected to the web of beam 242 and an elongated portion 248 which is welded to connecting member 100, at substantially the transversal centerline of the latter. That is, the transversal edge of variably shaped element 245 is welded to oblique elements 101 and 103 and to web 104 of connecting element 100.

FIGS. 20 and 21 illustrate connecting members 250 and 260, respectively, which are used as cable connectors. In FIG. 20, connecting member 250 comprises single-web connecting member 100 of FIG. 8, reinforcement element 251 longitudinally extending along, and welded to, the centerline of web 104 of connecting member 100, and coplanar plates 253 and 254 which are symmetric with respect to reinforcement element 251 and laterally extend from web 104. Plates 253 and 254 are welded to both web 104 and reinforcement element 251, and are bored with a single corresponding aperture to which the hooked end 259 of wind reinforcement cables 256 and 257, respectively, is engageable. In FIG. 21, connecting member 260 comprises L-shaped element 265 which is connected to the web of beam 252. Leg 267 of element 265 laterally extends from the web of beam 252 and is bored with two apertures to which the hooked end of cables 256 and 257, respectively, is engageable.

FIGS. 22-26 illustrate connecting members that are connected to a corresponding purlin. Any desired number of purlins can be connected to a beam by means of a corresponding number of connecting members.

In FIG. 22, connecting member 270 comprises connecting member of FIG. 6 connected to beam 272, and reinforcement element 278 longitudinally extending along, and welded to, the centerline of web 86 of connecting member 80. Web 274 of C-shaped purlin 275 is connected to reinforcement element 278 such that one transversal edge 279 thereof is in abutting relation with web 86 of connecting member 80.

In FIG. 23, connecting member 280 is a L-shaped element 284 wherein leg 286 is connected to the web of beam 282. Leg 287, which is perpendicular to, and of the same size as, leg 286, is connected to web 274 of C-shaped purlin 275.

FIG. 24 illustrates connecting member 290, which comprises two connecting members 110 of FIG. 9 connected to the two lateral ends of beam 292, respectively. A plate 295 is welded perpendicularly to, and has the same longitudinal dimension as, web 114 of a corresponding connecting member 110. Triangular rib 298 is welded to the bottom edge of web 114 and plate 295. Thus two coplanar C-shaped purlins 275 can be connected to connecting member 290, whereby web 274 of a purlin 275 is connected to a corresponding plate 295 and abuts web 114.

In FIG. 25, connecting member 300 comprises connecting member 110 of FIG. 9 connected to beam 302, triangular rib 303, and rectangular plate 45. Leg 304 of rib 303 is welded to flange 107 of connecting member 110, and leg 307 of rib 303 is welded to plate 45, which may also be welded to flange 107. Plate 45 in turn is connected to web 309 of Z-shaped purlin 305.

In FIG. 26, connecting member 310 comprises two mutually perpendicular plates 45C and 45D of FIG. 27, and triangular rib 303 which is welded to plates 45C and 45D. Plate 45C is connected to the flanges of beam, and plate 45B is connected to web 309 of Z-shaped purlin 305.

As shown in FIG. 35, a connecting member 450 can be connected to both a composite beam 10 and to a wall 455. Connecting member 450 comprises two symmetric parts 460 and 465. Each part comprises a web portion 462 connected to an adjacent web 7 of beam 10 by web fasteners 72, a wall abutting plate 466 connected to wall 455 by cold fasteners 457, and an oblique element 464 extending from web portion 462 to wall abutting plate 466 in mutual stabilizing contact with an oblique element or lip of beam 10.

Architects and civil engineers designing a structure which is supported by a beam system of the present invention benefit from a large choice of possibilities. Various combinations of the aforementioned beams and connecting members may be selected based on designed loads and stress concentrations. The load bearing capacity of a beam system can also be varied by changing the thickness of the sheet metal from which a beam or connecting member is fabricated, or by changing the number and location of the cold fasteners used to connect a beam and connecting member.

In beam system 350 illustrated in FIG. 31, for example, the largest stress concentration is found in the vicinity of corner 355 of connecting member 150 (FIG. 13), which provides a moment connection. A connecting member 150 is connected to post 154 and to ridge beam 214, and post 154 is connected to foundation attached connecting member 140. The two ridge beams 212 and 214 are connected by means of connecting member 200 (FIG. 16). The stress concentration in connecting member 150 may be reduced by increasing the thickness of the sheet metal from which connecting member 150 is comprised. In prior art moment connections, in contrast, the thickness of the entire significantly longer ridge beams has been necessarily increased in order to reduce the stress concentration at the moment connection, requiring time intensive and costly assembly operations. The stress concentration in connecting member 150 may also be reduced by increasing the transversal dimension of its corner sleeves. The stress concentration increases as the fasteners connecting the adjacent ridge beam are closer to corner 355 of the moment connection, requiring a larger number of fasteners. Thus the stress concentration to which the cold fasteners are exposed is reduced by increasing the transversal dimension of the corner sleeves.

In beam system 360 shown in FIG. 32, which illustrates a connecting member 120 (FIG. 10) connected to two beams 10, which are in turn connected to two pillars (not shown) by means of connecting members 140 (FIG. 12), respectively, the highest stress concentration is found in connecting members 120 as it is interposed between the two beams 10. The stress concentration may be reduced by increasing the thickness of connecting member 120, rather than having to increase the thickness of beams 10, as has been practiced heretofore in prior art beam systems.

FIG. 33 illustrates an exemplary beam system 380 assembled from many of the aforementioned beams and connecting members. It will be appreciated that other suitable beams and connecting beams may also be employed. The layout of system 380 is similar to that of prior art beam systems; however, the amount of steel used and the assembly costs associated with system 380 is significantly less than that of prior art systems due the use of the composite beams and connecting members of the present invention.

Beam system 380 comprises a plurality of posts 225, some of which are spaced by a span of L and some of which are spaced by a span of 2L. Front row 382 consists of 6 posts, central row 384 consists of 5 posts, and extreme side row 386 consists of 5 posts. Each post 225 is connected to the foundations by means of a corresponding connecting member 140 (FIG. 12). A ridge beam 212 or 214 is connected to a post 225 by the moment connection embodied by connecting member 150 (FIG. 13). A connecting member 200 (FIG. 16) connects a pair of ridge beams 212 and 214, and a pair of ridge beams is deployed along each side row such that the plurality of ridge beam pairs are mutually parallel. To connect connecting member 200 to a corresponding central post 225C, a horizontally oriented plate is welded to the bottom edge of ribs 207 and 208 (FIG. 16) that reinforce connecting member 200. A connecting member 140 is then connected to an uppermost portion of a central post 225C such that plate 146 of connecting member 140 is upwardly facing and is attached by cold fasteners to the plate welded to ribs 207 and 208. A plurality of purlins 305 are disposed perpendicularly to the plurality of ridge beams, in order to support a metal deck. A connecting member 300 (FIG. 25) is used to connect a purlin 305 to each ridge beam across which it extends and by which it is supported. When a purlin is attached to a moment connection, such as along front row 382, a connecting member 381 is used which comprises connecting member 150, to its flange 164 of corner sleeve 153 (FIG. 13) is welded rib 303 (FIG. 25), which is also welded to plate 45 connected to web 309 of purlin 305. Cross beam 10, such as the one deployed along extreme side row 386, is connected to each post 225 by means of a connecting member 389 comprising a first connecting member 80 (FIG. 6) connected to a post, a second connecting member 80 connected to the cross beam, and a horizontally disposed plate 198 (FIG. 15), which is welded to the approximate transversal centerline of the first connecting member and to the approximate longitudinal centerline of the second connecting member. Wind reinforcement cables are engaged with connecting member 260 (FIG. 21).

FIG. 34 illustrates an exemplary beam system 390 assembled from many of the same beams and connecting members used in system 380 of FIG. 33. Due to the increased lateral stability and strength to weight ratio of the composite beams of the invention with respect to conventional I-beams, and due to the use of connecting members which are in force transmitting contact with the beams, a beam made of moderate thickness sheet metal, e.g. 4 mm, can span a distance without bracing or bridging which is much longer than the maximum free span of prior art beams, e.g. 25 m. As shown, beam system 390 has the same number of posts 225 along its front row 382, i.e. 6 posts, as beam system 380 of FIG. 33, yet its central row 384 consists of only 2 posts, and extreme side row 386 consists of only 3 posts. Therefore the span along extreme side row 386 can be as much as 4L. Also, cross beams are unnecessary.

While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried out with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims.

Claims

1. A modular reinforced structural beam and connecting member system, comprising:

a) at least one composite beam having two oppositely oriented triangular closed heads and a transversally extending and longitudinally disposed web interposed between said two closed heads, each of said beams consisting of two separate members arranged such that corresponding head portions of said two members are configured with an essentially laterally disposed flange and are nested one within the other and that all pairs of adjacent elements of said two members, respectively, are in mutual stabilizing contact to produce each of said triangular closed heads; and

b) a plurality of connecting members, at least two of said connecting members being connected to, and in force transmitting contact with, one of said composite beams and another structural element, wherein at least one of said connecting members is connected to a flange and web of a composite beam by a moment connection.

2. The beam system according to claim 1, wherein the connecting member is connected to two composite beams by a moment connection to produce a combined beam, said combined beam being transversally adjustable.

3. The beam system according to claim 1, wherein the connecting member connected to a composite beam by a moment connection comprises at least one element which has the same thickness or is thicker than a corresponding element of the composite beans with which it is in force transmitting contact.

4. The beam system according to claim 1, wherein each member of the composite beam comprises a first head portion, a second head portion, and a longitudinally disposed web portion interposed between said first head portion and second head portion, said first and second head portions being configured with a corresponding essentially laterally disposed flange, an oblique element extending from a first lateral end of said flange to said web portion, and an oblique lip extending from a first lateral end of said flange and having a length considerably shorter than that of said oblique element.

5. The beam system according to claim 4, wherein the first and second head portions are configured with a single corresponding essentially laterally disposed flange, a first side of a triangular closed head comprising the two flanges of the two composite beam members, respectively, and second and third sides thereof comprising an oblique element of one of the composite beam members and a lip of the other composite beam member.

6. The beam system according to claim 5, wherein, with respect to the second and third sides of a closed head, the angular spacing between the oblique element and its corresponding flange is essentially equal to the angular spacing between the lip element and its corresponding flange.

7. The beam system according to claim 5, wherein adjacent sides of a triangular closed head are angularly spaced by an angle of 60 degrees.

8. The beam system according to claim 5, wherein each beam member is cold rolled.

9. The beam system according to claim 1, further comprising means for joining corresponding flanges of first and second beam members, for preventing relative transversal displacement of one of said beam members.

10. The beam system according to claim 9, wherein the flange joining means are cold fasteners.

11. The beam system according to claim 4, further comprising means for joining corresponding web portions of the first and second beam members.

12. The beam system according to claim 11, wherein the web joining means are cold fasteners.

13. The beam system according to claim 4, wherein the flange of the first head portion has a longer lateral, dimension than the flange of the second flange portion.

14. The beam system according to claim 13, wherein first and second members are identical, said second member being in opposite orientation than said first member such that the first head portion of the second member is nested within the second head portion of the first member and the first head portion of the first member is nested within the second head portion of the second member.

15. The beam system according to claim 4, wherein the flange of the first head portion has the same lateral dimension as the flange of the second flange portion.

16. The beam system according to claim 15, wherein the first head portion of a second member is nested within the first head portion of a first member and the second head portion of the second member is nested within the second head portion of the first member.

17. The beam system according to claim 13, wherein the first head portion of the second member is nested within the first head portion of the first member and the second head portion of the second member is nested within the second head portion of the first member.

18. The beam system according to claim 1, wherein apices of the head portion of a first member are stiffened by the head portion of a second member in which said first member head portion is nested.

19. The beam system according to claim 18, wherein a junction between the oblique element and web portion of the first member and a junction between the oblique element and web portion of the second, member are coplanar on a plane parallel to the corresponding flanges.

20. The beam system according to claim 1, further comprising a connecting member which is connected to a web of a composite beam by a shear connection.

21. The beam system according to claim 1, wherein a connecting member is connected to a composite beam by weans of cold fasteners engageable with corresponding aligned apertures bored in the connecting member and beam.

22. The beam system according to claim 21, wherein the connecting member is an off the shelf product which is connected in situ by means of cold fasteners.

23. The beam system according to claim 21, wherein the connecting member comprises more than one element which are welded together.

24. The beam system according to claim 21, wherein a connecting member is connected to a composite beam by means of cold fasteners and a reaction plate insert attached internally to said beam.

25. The beam system according to claim 21, wherein a connecting member is configured as a sleeve having selected transversal, longitudinal and lateral dimensions, and is adapted to completely surround and to be in mutually stabilizing contact with a portion of a composite beam perimeter having said selected dimensions.

26. The beam system according to claim 25, wherein the sleeve comprises two cold rolled elements that are welded together.

27. The beam system according to claim 25, wherein the sleeve comprises a single element; two adjacent edges of which are welded together.

28. The beam system according to claim 27, wherein the sleeve comprises two adjacent half sleeves that are connected to the two lateral sides, respectively, of a beam.

29. The beam system according to claim 21, wherein the connecting member is configured with only one web.

30. The beam system according to claim 29, wherein the web of the connecting member is substantially shorter than the web of the beam to which the connecting member is attached.

31. The beam system according to claim 21, wherein a connecting member comprises a plate in force transmitting contact with a web or flange of a beam.

32. The beam system according to claim 31, wherein the connecting member comprises two angularly spaced plates and an element extending between, and oblique with respect to, said two plates.

33. The beam system according to claim 21, wherein the connecting member further comprises at least one rib.