US1969312A - Structural unit - Google Patents

Description

Aug 7, 1934. I s. MACOMBER STRUCTURAL UNIT Filed Sept. 29. 1930 4 Sheets-Sheet 1 Aug. 7, 1934. s. MACOMBER 1,969,312

STRUCTURAL UNIT Filed Sept. 29. 1930 I 4 Sheets-Sheet 2 61/252027? 57A/v4 5y Mcowaze S. MACOMBER Aug. 7, 1934.

STRUCTURAL UNIT Filed Sept. 29, 1930 4 Sheets-Sheet I5 wANZZKZZZ/Q M T M m R QM m S. MACOMBER STRUCTURAL UNIT Aug. 7, 1934.

4 Sheets-Sheet 4 Filed. Sept. 29

A/Zw/vazze Tra@ /EK v 30 panying drawings.

Patented Aug. 7, 1934 STRUCTURAL UNIT -Stan1ey-Macomber, Edgefield District; Ohio Application September 2911930;Serialflflok485,183

' cl Claims.

-My.tinvention particularly relates to alight -truss-likestructure adapted for use instead of -beamstin carrying light loads as in the case of -joists in floors and the'like; and may also be advantageously employedas a column, as a roof :purlin, and as a reinforcement for concrete floors -Ai'urther object is the provision of a structural unit of this type wherein end mem- 'bers are provided having continuous supporting surfaces in order to secure flexibility, orin other words permit variation in the span lengths for which any particular truss can be used Still another object is to provide in such a structural unit-for variation in the span length, or in other words an extension of the normal length of the span using thesame elements and thus avoiding additional cost in the manufacture of separate trusses of different lengths. Still another objectis toprovide joist end pieces which willpermit the use'ofa net span joist end for a plurality of spans by the use ofadditional strengthening members connecting the ends of the web and the bottom chord and endpieces, a standard-web being utilized for such series of joists, the'length of-top and bottom chords being :varied for each individual joist of the series. 'Various illustrative iorms of the constituent elements of my improved unit are hereinafter .-fully described and also shown in the accom- The invention is an improvement particularly of the structure showndescribed and claimed in UxS. Patent No..1,651,032, of November 2 9,

1927, issuedupon my improvements in Strucvantages as to the economy of metal inherent in a truss type of structure andat the same time plane indicated by-the line 12-12, Figure 8;

is not subject to the objections in a truss of lack of flexibility in the matter of the distance apart of the points of support, these-disadvantages being obviated by the use in theunit of beam ends-which afford amultiplicity of points of support for the whole unit and are tiedinto the centraltruss portion so as to adapt-the unit'as a whole to sustain-a predetermined load irrespective-of the points of support within the .mim'mum and maximum spans for -which the unit is designed.

The improvements in the construction shown in this instant application over the invention .shown in said patent reduce the cost of labor andmaterial entering into the production of ,unitsof 1 .this general character (afiord somewhatmore standardization of zthe constituent in Figure 2;

plane indicated by the line 20'20,"Figure ""-1'8;

partsentering into the different units by-per- The annexed drawings and the following de- 69 scription set forth in-detail certain means embcdying my invention, such disclosed means constituting, however, only a. few of the various tforms in-which the principle of the invention may be illustrated. V 5

In said annexed drawings:

l Figure l is-aside elevation of a complete structural unit embodyingone form of end piece adapted :to 'co-operate -with the central truss portion to produce the complete unit of the desired character and advantages; Y

- Figure 2 isa side elevation,'upon an enlarged scale; of one endof the unit shown in Figure 1;

:Figure 3 is a plan view of the unit end shown p Y I r '75 Figure 4 is a bottom plan-oi the unit end shown in Figures-land 2;

Figure5 is a vertical sectionptaken in the plane indicated by the line 55, Figure 2;

Figure 6 is a horizontal section-takenin the plane indicated by-the line 66, FigureZ;

Figure 7 is a-perspective view ofthe form of in Figure 8; V

. Figure 10 is a vertical-section, taken in the plane indicated by-the-line 10-10, Figure '8;

Figure 11 is a horizontal section, taken in the planeindicated by the line 1111, Figure 8;

Figure 12 isa vertical section, taken in the truss end Figure 19 is a plan 'view of the truss end shown -in Figure 18;

Figure '20'is a vertical SectionQtaken'inthe Figure 21 is a horizontal section, taken in the plane indicated by the line 21-21, Figure 18;

' Figure 22 is a side elevation of a complete structural unit utilizing the form of truss-end shown in Figure 13, this unit being adaptable for a series of spans, and the web-member of the unit consisting of three connected parts, a central portion and two end portions, of which the end portions are of somewhat heavier material per unit length than the central truss portions; Figure 23 is a View similar to Figure 22 of a complete structural unit, utilizing the net span end shown in Figure 18, this unit being adaptable for one span only; v

Figure 24 is a view similar to Figure 23 in which the same end piece as that shown. in Figure 23 is utilized but the span .adapted to be served by the unit is somewhat longer than the span served by the unit shown in Figure 23, the web-members of Figure 24 being reversed in positions from those shown in Figure 23, the chord members being somewhat longer in Figure 24, and additional end web extensions beingshown in Figure 24 connecting the ends of the reversed web-members and the bottom ends of the end pieces and the outer ends of the bottom chord member; 1 1

Figure 25 is a detailed illustration of certain end web extensions whichwill serve as the additional end filling members between the webs and the end pieces for a'series of joists adapted 'to serve varying spans and utilizing the same Web-members and end pieces;

Figure 26 is'a side elevation of substantially one-half of a structural unit adapted to serve a span somewhat greater than that served by the unit of Figure 24 by the use of a difierent end filling member than that shown in Figure 24 and somewhat longer chord-members, together with the same web-members and end pieces'as those shown in Figure 24;

Figure 28,- of a unit in which plain platesare used as chord-members;

Figure 31 is a side elevation of the ends of a unit in which double T sections are used for chord-members; a

Figures 32 and 33 are vertical sections, taken,

' respectively, in the planes indicated by the lines 3232 and 33-33, Figure 31;

Figure 34 is a section, similar to Figure 32;

36-36 and 3'737, Figure and Figures 38 and 39 are side elevations-of the ends of units which have somewhat modified end structures from those previously shown, and which will hereinafter be described in detail, these different details of ends' being utilized 'eitherwith the T or the double T section, the

particular embodiments herein shown being the double T in Figure 38 and the single T section in Figure 39. Referring to the annexeddrawings in which units shown in said figures.

the same parts are indicated by the same respective numbers in the several views, all of the forms of structural units shown in these drawings consist primarily of a central truss portion combined with strengthening and stresstransferring supporting ends interlocked with the truss center so as to withstand the support reactions and to co-operate with the truss center to form an integral unit adapted to give the desired service. In the first three of the several forms illustrated in the drawings, Figures l to 17, inclusive, these supporting ends are extended and so interlocked with the truss center as to provide a plurality of points of support, or continuous supporting surfaces for a materialdistance, whereby one unit will serve for, any desired span of a plurality of spans,

thus obviating the necessity of making an entirely separate unit for each span and thus permitting a comparatively small number of difierent units to serve for a comparatively large number of different spans. As-hereinafter fully described, the fourth form of the invention shown in Figures 18,19, 20, and 21, is designed S for a single net span, butmost of the compo-.-

nent parts of this net span unit are comprised of standard elements and only slight changes of a nature comparatively easily made permit the production of different net span unitsto serve the spans necessitated by the specifications of 05 different jobs within a given range of spans. The central truss portion of the units'is comprised of a top chord member and a bottom chord member combined with a'connecting web member,jthe particular form of truss illustrated 0 in these figures being the well-known Warren truss and having parallel twin bars 1 and 2 comprising the upper chord, and parallel twin bars 3 and 4 comprising the lower chord and suitably spaced from the upper chord, and anf'1' 5 intermediate connecting continuous and reversely bent bar 5 serving as the web, this-web being rigidly secured at its bends intermediate the twin-bar upper and lower chords, preferu, ably by welded joints 8 and 9. Preferably,the

web-member consists of a central portion and two'end portions connected'at their inner ends to the ends of the central portion and formed of material of greater weight and gauge per unit length than the central portion. Figures 22 and 23, 24 and 26 show the web-member so constructed of difierent connectedelements and these elements will be hereinafter fully described in connection with the description of the inclusive, show modified" chord and trus'sstructures and some detailed end-piece variations adaptable for units containing the improvements of the invention.

Figures 2'7 to 399 Referring particularly to the form of the invention shown in Figures 1 to 7, inclusive, the unit supporting-end extension which may be a casting comprises a base 11 and a vertical strengthening member 10 extended at right angles to the base 11 and formed at its inher end with an inwardly and downwardly projecting portion 10', the base 11 being formed with a similar inner end portion 11, the inner bottom end of this combination support and.

strengthening member being integrally secured to the end web member 6, preferably by a welded joint '7. Inasmuch as the stresses which the 'members 10" and 11 must withstand decrease in amount from the downward bend of the 'members-*-101-0- and llll to the joint ill) nee -s12 "thereof with the web member 6,--these members .10; and 11' graduate in width from top to hottom, as is- 1 clearly shown in Figure 5. Upon the topof tLre-member -lO is a horizontal plate twin-bai upper' chord 1- 2-- are rigidly secured 1' and 2- r-igidlyabut. Thebottom end of the ---wardly-projected extension 14, Figure 6-,- against -the sides of -which-the ends of the twin-bar bottom chord 3-4- are rigidly secured preferably bywelded joints 15; Figure 4.

In the form of invention shown in: Figure 8 =to- "12,-which--may be of forged steel construction, theverticalstrengthening plate l'l-having an inward--and downward end-portion 17 -is -rigidly secured to supporting base angles 18 and 19 having'inner and-downwardly projecting end portions 18' and -19, and-the extending end portions 18' and 19' terminating somewhat -short of -the*-bottomof the member' 17-where '-the strcsses-to-be-withstood-- are so compara- -=tively slight as to make unnecessary any further extension of such strengthening members-18' and- 19'. In this form of -device the ends of the top twin -bars 1-and2 are'welded by joints 21 to-the sides oi theinner end of the vertical plate l'land the ends-ofthe twin bottom bars 3 and 4 are-weldedby joints- 20 to the sides of the inner end of v thedownwardly extending plate portion 17'. g

*In the form of-device shown in Figures 13 to -17; inclusive-the -unitend piece comprises -a vertical plate-26 secured by-welded joints 28 to a relatively light angular-base plate 27, the-lat- -ter' having a-short inwardly and downwardly extended end portion 27'. In this form of construction -'the connecting --stress-transferring -member between the upper supporting extension and-the bottom truss-chordconsistsofa bent bar having portions"29,-30,- and=31, clearly shown-in-Figure 13,-which form an endless band by reason of the welded 101111335 connecting the bottom of the members 29-and 31, as clearly shown in Figure 13, the bar-inember--29being secured to the downwardly extending plate f member 27'- by a welded joint 33' and also being secured to the inner edge of the --vertical strengthening plate 26 by a welded joint-34. In --this form of construction "the twin bottombars -3 and 4 are secured by welded joints-37 to an outwardly extended horizontal end portion 32 ofthe bar-member29. The bottom of the end web member 6 is secured to thebottom of the --bar 31, between the bottom chord bars 3 and 4, by a welded joint 36.

The three forms of the invention-hereinbefore ,-des cribedpermit the use of each of these end "pieces. for a pluralityof spans by reason of the "extended reinforced bases or end supporting members and the nature of the connections between the units truss center and the reinforced supporting ends. In the form of device shown in Figures' 18 to 21, inclusive; the structure is such as' topermit theuse of the end piece for-only a ynet span, unless some changes aremadein the .unit as a" whole, ashereinafter fully described.

' to-Ithe sides of the plate 10- adjacent fthe'inner endofthe=1atter,+preferably by welded joints 16; theiinner edge'of the-top plate 12for-minga stop 13 againstwhich theouter-endsofthebars member 10 is formed with a--horizontal outa-seriesof units utilizing such-i an-:end piece so that only :slight changes-which can 1 be convenientlyandeconom-ically'made permit the design- 3 ing of: "the -same kindof 1 net span @unit'. for various net spans. xFor-thejoist utilizing -:the end: piece shown in -'Figure=:18,= I utilize a: web h'avinga standard numberaof. bends and a standardze-bendiangle. I: also utilize supporting-base -membere :42,--suitablei for1 mounting upon coltwat-strengthening plate 41 being. secured to :thebaseAZ by welded joints: 43. :The. inner end oftthebase 42 is iinwardly and downwardly extendedzto form a connecting/member 42'v to l 48, thisbarred having. an upper and. inwardly :-extendings endlmember ifi secured to the .front edge of. the. .viertical. strengthening plate 1 41 by a welded j'oint 47,: the-bottom: end of the. bar

-' 4etbeing secured toitthe end of. the web. mem- 'umnsor walls, separated by anet span, a verwhicl1-.a-bar 1 44. -.issecured by. a welded (joint t...

1 ser-ved=by.. a joist halvingthe standard 'end piecef ishowndn. 'Figure. 13 and having :the same..web- .=-member and :chord members as are utilizedwith lithe neti span .end..piece.shown iniFigure 18. s flowever if.tspansl greater than thesminimum spansa'dapted tube-served byhawjoisti having a wstandardiend piece, such asv shQWnin Figure g $13, 8.16 to lbe servedi 'byf joist having: netspan -end rpieces and adapted for service within the .seriesrof-spans, served-by. the endpieceof Fignure -13,-' :then.some changes are necessary in the combination of; elements comprising the-joist, and such-:jchanges will .now be described in "detail. i v Referring-particularly torFigures 22'to .26, iniinclusive; it.-is presumed that, Fligure 22 representsa certain joist having standard spanends izfurnishing ax multiplicity of supports and incorporated with the truss center so as toz be capablenof-i serving for any desired span of a 3125 cpluralitylof spans. Figure 23 illustrates a joist havinglnetuspanends and capable of serving the'minimumispan-which can be served by'the Ljoist-fshown.in-Figure -22. 11f it is desired to abridge a spanbetween :the minimum and maxii-mum spans'served by the joist shown in Figure ='i22,.and.Stil1 utilize a. net span end, this can sabeidonexby a slight reorganization of the joist x:-..which'==willentail somewhat/extra labor but,

1.:byfreason offithe saving. of the material, willg bean economy, ifi at. leasta minimum number I of joistsbf. ithiS same specification .are needed. lfhis reorganization is. effected byreversing'the web-53shownin2'Figuresi22 .and123 in the :mannershown in 'Eigure' 24. The up lower chords 55-and '56 are lengthened out,

in accordance with the span for -which-the 'joist is specified, thenet span end pieces. are 7 moved out the necessary distance and the space per and 154. 0

between the bottom of the bar -44-of the net span endand -the top 54" of the reversed-end web-member' is filled'by an additional end-web "extension 5'7 which is secured top-and bottom between'the twin bars of the top chord 55. and

However; several standard elements-enter-iptta *the :bottom' chord-;56,- at the 'j0ints where the I bar, the same web-member and the same net span end pieces can, be utilized for any desired span between the minimum and maximum spans served by the corresponding joistshaving the standard span end pieces. What is meantby lengthening out the chords is that other upper and lower chords of suitable length for the I increased span are utilized instead of the chords which are suitable for the minimum span.'In.

other words, the increased span is accommo- .dated'by the same web-member, in reverse position, and the same net span end pieces, as accommodated the lesser span, and the only new elements are the chords of suitably greater length and the suitable end web extension.

number for. the various spans between the, minimum and maximum spans of the corresponding standardend joist. Assuming, for instance, that thevariation between the minimum and maximum span is 11 inches, then 3 such bars would J serve for the entire dillerentiahsuch bars being illustrated in Figure 25. For purposes of illustration, it might be assumed that, bar 57 would serve for an increase of from inch to 2 ,4; inches over the minimum span at each end of the joist; bar 58 would serve for increases from.2 to' 4. inches at each end of the joist; and-bar 59 would serve for. increases from 4 to 5% inches at each end of the joist. 0f 'course, a 12inch differential in span would amount to 6 inches at each end of the joist. If

the increased span is (i-inches or more at, each end, then the joist of the next. series would be utilized, either a joist for the entire-series having standard span ends, or a joist having net span ends and .filling bars, if the increase in span is not a foot or a multiple of afoot, by'

I reversing the web and using the proper additional end filling bar. In Figure 26, it is assumed that the increase at each end has beenso great as-to make necessary the use of the filling bar 59 WhlClh'iS the bar utilized for the higher spans of a series, when using net spair ends. V

There aresome suggestions in Figure 25 of the approximate sizes of a series of end web extensions and theproper angles at. which they can be utilized for different spans 'of' a series.

of-- spans. It is assumed, for instance, that the three bars shown in Figure 25 will serve for the series of spans which would be servedby a joist of the character shown in Figure 22, if net span 1 ends, such as shown in Figure 23, were utilized instead of standard span ends. Of course, for the minimum span, no one of .the bars shown in Figure 25 would be used because the joists are so designed that for this minimum span the 'net span'ends only willserve," and the webmember is utilized in its normal'position and not reversed-as isthe case when the joist is utilizedfor the greater spans and one of the filling bars 57, 53, or 59 is used.

It is preferable to subdivide the web-member .into three sections, a central section 51, and two end sections 52 which-are integrally connected between the top and bottom chord members to the respective ends of the central webmember 51. Because of the stresses which they respectively withstand, the, end web-members 52 arev of somewhat greater weightand gauge The additional end filling bars are several in .to the end web-member 6.

per unit length than the central web-member 51, and they are so shown in the accompanying are indicated, by the number 54.

Referring particularly to Figures 27 to 39, in-

clusive, inwhich various modifications of chord structures and unit-endstructures are shown,

for the purpose of illustrating some of thepossible variations coming within the principle of my improvements, I show in Figures 27, 28, and 29 a unit-end in which T-sections 61 are utilized as top andvbottom chords. Thevertical end plate 26 is secured by welded joints 62 to the bottomof the ends of the top chord 61, this chord being extended outwardlysubstantiallyto the end of the unit supports. A bent end bar 29-36-31, such as shown in Figure 13, is secured by welded joint 63 at the top tothe bottom of the upper chord 61 and'by .welded joints 64 and 66, respectively, to bottom chord 61 and The web-memberis secured by welded joint 65 to the top of the bottom chord 61 and by welded joint 67 to the bottom of the upper chord 61.

Figure 30 illustrates the use of plain plates 68 as chord-members ,to the respectively opposed ,l'aces of whichthe top and bottom of the webmember 5 is secured bywelded areas 69 and 70,, respectively.

, In Figures 31, 32, and 33, Ihave illustrated the use of double T-sections 71 for chord-members, between the opposed webs72 of which the vertical end plates 26 are secured by weldedarea .73, and the end bar 29-30-31 is secured by to the chords.

Referring to Figures 35, 36, and 37, I show a split rail comprised-of the upper member having the flange 76 and the web 7 8 and the lower member having the flange '77 and the web 79 which are utilized for the top and bottom chords. The securing of the associated elements to the chordmembers by welded areas is similar to that illustrated in Figure. 2'7. v I Figure 38 shcws an end-piece, modified in details, particularly as regards the shape of the vertical end plates 80 and the connection thereof with the bent end bar 29-30-31. I have illus: trated this end-piece as associated with double T chord-members 71 between the webs 72 of which the vertical end plates 80 are secured, as also the bent bar 29-30-31, and the angles .of the web-member. The end plates 80 are cut square at the ends and the inner end thereof is secured to the bent end bar 29-30-31 by the welded area 83. The underlying supporting base of the end-piece is formed by a horizontal plate 81 to which the bottom of the vertical plates 30 are secured by welded areas 82, this plate 81 having an inwardly and downwardly extended end portion 81 to which the member 29 of the bent bar is secured by welded areas 84.

In Figure 39, I have illustrated a modified end structure in which single i -sections are utilized as chord-members, the modification consisting principally in extending the outer member 88 QUhhQ l par, 8 9.9 v tical y q a ly, and the inner member 90 thereof outwardly as well as downwardly, and in securing the end web-member 91 to the top of the bar member 90 instead of to the bottom, as is true of the web-member connections heretofore shown with this general type of end-piece. The supporting end base 86 is secured to the vertical plate by welded areas 8'7, and has a downwardly extended vertical end extension 86 secured to the bar member 88 by welded area 92, this bar member 88 being also secured to the inner edge of the vertical plate 85 by welded area 96. The bar member 89 is secured to the bottom of the T chord 61 by welded area 93 and the bottom of the bar member is secured to the bar members 88 and 9'7 by welded area 94. This bar member 97 is an inwardly extended end extension of the bent bar, as distinguished from the outward extension 32 shown in Figures 13 and 38, for instance, this bar end extension being secured to the lower T chord 61 by means of welded area 95. The end web-member 91 is secured by welded area 98 to the bent bar and to the upper chord 61.

These figures 27 to 39, inclusive, are intended to portray some of the many modifications of chord structures and unit-end structures which may be utilized to form structural units containing the improvements of my invention.

What I claim is:

1. An end member for truss-like structural units comprised of a plate forming a supporting base; a strengthening plate secured to said base and extended upwardly at right angles thereto and adaptable for connection to an upper chord of a truss, said base plate being extended inwardly and downwardly at its inner end; a stresstransferring bar secured intermediate its ends to the inner end of said strengthening plate and also secured to the downwardly-inclined portion of said base plate, both ends of said bar being extended downwardly and rigidly secured together at their bottom portions, said bar being formed adjacent the bottom with means adaptable for attachment to a truss chord.

2. An end member for truss-like structural units comprised of a plate forming a supporting base; a strengthening plate secured to said base and extended upwardly at right angles thereto and adaptable for connection to an upper chord of a truss, said base plate being extended inwardly and downwardly at its inner end; a stress-transferring bar rigidly secured intermediate its ends to the inner end of said strengthening plate and also secured to the downwardly-inclined portion of said base plate, both ends of said bar being extended inwardly and downwardly and rigidly secured together at their bottom portions, one of the bottom ends of said bar being formed with a horizontal extension adaptable for attachment to a truss chord.

unit-ends, the length and angularity of said web" end extensions varying according to the span between said unit ends.

4. In a truss-like structural unit, the combination of top and bottom chordmembers; a web-member connecting said chord-members, the latter extending at the ends beyond the ends of said web-member; reenforced unit ends integrally connecting the adjacent chord-ends and extending outwardly thereof and having unitend bearing portions; and outwardly and downwardly extended end web extensions secured to the ends of the web-member, to the top and bottom chord-members, and to the reenforced unitends, the length and angularity of said end web extensions varying according to the span etween'said unit ends.

5. In a truss-like structural unit, the combination of top and bottom chord-members; a webmember connecting the central portions of said chord-members; end web-members connecting the respectively adjacent end portions of said chord-members and connected to the respective ends of the central web, said end webs being heavier per unit length than the central web, said chord-members at the ends extending beyond the ends of said end webs; reenforced chordend extensions secured to the top chord and forming unit-end bearing portions and having downwardly inclined extensions secured to the adjacent ends of the bottom chord; and outwardly and downwardly extended end web extensions secured to the ends of the end webmembers, to the top and bottom chord-members, and to the reenforced chord-end extensions.

6. An end member for truss-like structural units comprised of a plate forming a supporting base; a strengthening plate secured to said base and extended upwardly at right angles thereto and adaptable for connection to an upper chord of a truss, said base plate being extended downwardly at its inner end; a stress-transferring bar rigidly secured intermediate its ends to the inner end of said strengthening plate, said 'bar being doubled upon itself for connection at a bend to the upper chord of a truss, and secured to the downwardly inclined portion of said base plate, the two ends of said bar converging downwardly to a bottom joint adaptable for connection to the lower chord of a truss and having an integral extended terminal member.

' STANLEY MACOMBER.

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