US2031007A

US2031007A - Grid or grating

Info

Publication number: US2031007A
Application number: US613753A
Authority: US
Inventors: Walter F Schulz
Original assignee: TRUSEON STEEL Co
Current assignee: TRUSEON STEEL Co
Priority date: 1932-05-26
Filing date: 1932-05-26
Publication date: 1936-02-18
Anticipated expiration: 1953-02-18

Description

Feb. 18, 1936. w. F. SCHULZ 2,031,007

GRID OR GRATING Filed May 26, 1932 3 Sheets-Sheet l Fig. 1.

Feb. 18, 1936. w. F.SCHULZ 2,031,007

GRID OR GRATING Filed May 26, 1932 3 Sheets-Sheet 2 .4 Q A k i u "H M 1 R 0 n1 nu .n

\ I H I] I! I! I J i v H H H 1 II I Patented Feb. 18, 1936 GRID 08 GBA'I'ING Walter F. Schulz, Youngstown, Ohio, assignor to Truseon Steel Company, Youngstown, Ohio, a

corporation of Michigan Application May 26, 1932, Serial No. 613,753 28 Claims. (CI. 94-30) The primary object of my invention is to provide a novel combination of special forms of metal, including a special method of welding. and that combines and cooperates with concrete or similar material, to form a flooring supported upon other frame work, and of such construction as to provide a relative maximum of economy in production and installation and of efllciency in use.

The structure of the invention may be used with or without the concrete for ceilings or wall structures, with or without separate covering of the open side'thereof.

Specifically the use of the structures of my invention for flooring of certain types of bridges will illustrate and exemplify its advantages for employment in various capacities.

Where a structure is designed to carry a superimposed load of the character common on floors of bridges or otherwise and the well-known wrought metal T-bar can be used, reversed as shown in the accompanying drawings, such T-bar provides the most economical method of resisting the stresses of superimposed weight, where properly combined with concrete or similar material. In such use, the ,horizontal extensions at the bottom of the bar as a reversed r are known as flanges and the vertical central portion as the web. The stresses of superimposed pressure are exerted chiefly in tension at the bottom, decreasing upward toward the neutral axis in the web,

at which point compression stresses commence and increase to the top of the web. of structural shapes of such general type, the most economically produced in a given tonnage of like sectional areas are flats or plates, squares and rounds, next angle bars, next T bars, and most. expensively I and H bars or beams. Wrought metal is relatively strong in tension and weak in compression. In the T-bar of wrought metal the angle portion can be rolled to the required predetermined sectional area to furnish the tensional resistance required without undue waste of metal in the web (or in top flanges such as the H-bar) where not required on account of resistance to compression being otherwise provided. In the preferred form of my construction, the compressive resistance is principally provided by concrete or similar relatively inexpensive material strong in resistance to compressive forces and furnishing at its surface a desirable tractive medium for trafic.

The edges of the flanges of T-bars properly formed most advantageously lend themselves to union by economical welding to such ex e t 88 to thereby unify the action of the flanges.

may be required, and the thinner upper edges of the webs to the special welding of the special cross bars hereinafter described.

An embodiment of the invention is illustrated in the accompanying drawings, wherein: 5

Figure 1 is a plan view of a unit or slab.

Figure 2 is a perspective view showing the same partly fllled with concrete.

Figure 3 is a perspective view of the meeting portions .of two units showing the relation of 10 the anchoring or tie elements thereof.

Figure 4 is a detail cross sectional view of the parts asshown in Figure 3 when fllled with concrete.

Figure 5 is a similar view but taken ferent point.

Figure 6 is a cross sectional view on the line 66 of Figure 5.

Figure '7 is a perspective view showing the use of angle bars instead of T-bars, holes for bolting, 2o riveting, or plug welding to unite the structure to a metallic supporting framing, and the filled V form ofcross bars welded into the tops of the webs so as to be flush with the surface thereof.

Figure 8 shows the use of plates instead of T or angle bars.

Figure 9 is a detail sectional view showing how an angle bar may be employed for completing theoutermost side of the-structure.

In my preferred form of construction the desired number of T-bars of the desired length and dimensions are assembled side by side in the shop with the flanges I constituting the base of the structure and with webs 8 upstanding in spaced parallel relation. The abutting edges of the flanges of each sectionare welded either continuously or at spaced intervals, as shown at 9, with or without staggering, as may be determined with reference to the stresses to be met, and so as Deso pending upon the area to be covered the structure may be completely fabricated in the shop, but usually it is preferable to produce the same in units or sections to be assembled on the job. Such a unit or section is shown in Figure 1.

Where economy of fabrication is justifled with reference to requirements, angle bars Ia may be employed instead of T-bars, and where T-bars are employed, an angle bar of proper width in the horizontal angle may be used to close an outer channel of the structure after the sections have been assembled to the requisite width of the flooring or roadway as indicated at 'Ib in Figure 9.

Where only grating or open flooring is required, and tensile strength at the bottom of the strucat a dif- 5 ture does not necessitate the use of T-bars or angle bars, plates 'lc may be used.

To unite the T-bar, angle-bar or platesections at the top and provide, with the top of the webs, metallic protection against the breaking down of the concrete surface of the floor or roadway and against slipping or skidding upon the surface, cross-bars III are provided. The cross-bars III are preferably of approximate filled-V section, preferably slightly blunted at the tip and of shape in section approximately as best shown.

Using an approximate filled-V section for welding to the thinner vertical webs I, la or To, the heat of well-known resistance weldingndifiused over the surfaces of the cross-bars, is concentrated at the point of the V and causes the metal of the web first to melt at such point of contact. Under continued application of heat and pressure, the metal of the web and cross-bar is progressively melted along lines corresponding to the downward sides of the V until the V-bar is brought to a point where its upper surface conforms substantially to the upper edge of the web, and complete welding of the V-bar to the web occurs at all points of contact. As a further result, the surfaces of the metal conform substantially to the surfaces of the concrete when poured and the roughness incident to other methods of welding other forms of cross-bars is avoided. This welding process is more fully explained in my Letters Patent No. 1,973,113, dated September 11, 1934.

will be noted that one set of alternate bars projects beyond one outer side web 8 and is downturned to form anchor hooks ll, while the barsbetween said hooks terminate at the said web. These latter bars, however, extend beyond the opposite side of the unit and are correspondingly formed with hooks. Preferably also openings 12 are formed in the meeting edges of certain of the flanges 1, these openings being provided for means used to fasten the structure to an underlying sup-' porting frame.

The units or slabs as shown in Figure 1, are preferably fabricated at the factory and may be of predetermined standard lengths or made of special size for the particular place where they are to be used. If desired they may be either flat or crowned.

The sections of my structure constituting, with the concrete or like material, the floor or road- 'way, are supported upon spaced portions of the main framing structure, one of which is indicated at i2a. They are held firmly united to the framing structure and against longitudinal movement under tensional strain by bolting, riveting or welding through holes I3. I prefer welding by the process known as plug welding through such holes. But any form of welding may be employed. By this form of construction I provide by the flanges, where required, and by the part of the web below the neutral axis, and to the extent required, the maximum of tensional resistance with a minimum of expense in a structure of this type.

The channels can then be filled in with concrete. As a matter of fact the grid or grating will itself support trafiic and machinery for laying the concrete. In other words concrete mixers or trucks carrying the concrete can pass freely thereover. The concrete is filled into the channelsuntil flush with the upper edges of the webs 8 and cross bars In, as shown at H in Figures 2, 4, 5, and 6. When so filled in a complete floor, deck or roadway is provided in which the concrete is in theform of continuous elongated bars anchored down by the cross bars Ill, the upper edges of the webs I and cross bars serving as a non-skid surface and directly resisting the abrasive action of the mum on the concrete. Moreover as the cross bars taper downwardly they overlie the margins of the concrete on opposite sides of the same, providing chamfered corners at the top that prevent the spawling of the concrete under trafllc. Fur thermore it will be obvious by a comparison of Figures 3, 4, and 5 that the concrete between adjacent units serves as a tie in which the hoc'rs II are embedded, thus creating an effective joint between adjacent units. Atthe same time the projecting hooks I l extending substantially to the.

unprojecting ends of the cross bars of the adjacent units provide substantial continuity of the metal surface throughout the area.

From a structural standpoint the concrete or similar material, cooperating with the portion of the web above the neutral axis, provides the compressive resistance required. Moreover by the use of the form of cross bars and the method of welding above described, the tops of the webs are united and form a grid not only cooperating with the concrete in producing traflic cohesion without having any protruding surfaces, but also without weakening the web in resistance to the negative bending moment, the latter as next explained.

While the principal stresses under superimposed loads are those of compression and tension Inthe production of the gridor grating it between the points of support of the spans as above stated, normally greatest under a load at the center of the span, there is a change into a negative bending moment, a reversal of such stresses, at and adjacent to the points of support of such a structure upon the main framing. If the .webs were cut at their tops for the insertion of cross bars or members, it would weaken the webs through lack of continuity at the points of tensional stress of the negative bending moment. By the present method of construction and welding applicable to the preferred form of cross bars, continuity of the upper portion of the webs is maintained and the full strength thereof in tension maintained even though the surface of the cross members is brought flush with the top of the web.

By suificient welding between adjoining edges of the flanges of the T-bars or the edges of anglebars to adjoining sides of angle-bars, resistance to tensional stress transversely of the length of the T-bars is provided, and the bottom part of the structure becomes in substantial effect a plate extending throughout the entire lower area, re-

sisting all torsional stresses as well as longitudinal and transverse tensional stresses. The concrete or like material, cooperating with the intervening webs, resists transverse as well as longitudinal compressive stresses. The cross-bars resist tensional stress in any transverse negative bendin moment.

From the foregoing, it is thought that the construction, operation and many advantages of the herein described invention will be apparent to those skilled in the art without further description, and it' will be understood that various changes in the size, shape, proportion and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

What I claim is:

1. In a wrought metal structure of the type described, a set of flanged bars with the flange of one bar substantially abutting the flange of the adjacent bar, and means uniting the said abutting flanges o! the bars to adjacent flanges to provide in the flange portions of the bars required tensional resistance in angular directions.

2. In a wrought metal structure of the type described, T-bars located side by side with the opposite flanges of one substantially abutting the flanges of the bars on opposite sides thereof, and means uniting the said abutting edges of the flanges thereof, to provide in the flange portions of said T-bars required tenslonai resistance in angular directions.

3. A structure as described in claim 1 combined with a flller to provide additional resistance to compression strains.

4. A structure as described in claim 2 combined with a flller to provide additional resistance to compression strains.

5. A structure as described in claim 1 combined with cross bars connecting the tops of the webs of the flanged bars.

6. A structure as described in claim 2 combined with cross bars connecting the tops of the webs of the T-bars.

7. In a wrought metal structure of the type described, 13. series of supporting bars located side by side providing spaced webs, and cross bars connecting the tops of the webs and press welded into said tops with their upper faces substantially flush with the top edges of the webs.

8. A structure as described in claim '1 in which the cross bars. are substantially V-shaped in cross section.

9. A structure as described in claim 7, and in which the lower edges of the supporting bars are united and a filling of cementitious material is located between the webs to provide additional resistance to compression stresses. v

10. A structure as described in claims 7 and 8 and in which the lower edges of the supporting bars are united and a fllling oi! cementitious material is located between the webs to provide additional resistance to compression stresses.

11. A wrought metal structure of the type described comprising a series of inverted T-bars located side by side and having the edges of their adjacent flanges united to resist transverse tension strains, and cross bars connecting the tops of the webs of said united T-bars.

12. A wrought metalstructure of the type described, comprising a series of inverted T-bars located side by side and having the edges of their adjacent flanges united to resist transverse tension strains, cross bars connecting the tops of the webs of said united T-bars, and fllling in the spaces between the webs of the T-bars and acting to resist compression strains transmitted to the said webs.

13. A wrought metal structure of the type described comprising a series of inverted T-bars located side by side and having the edges of their adjacent flanges united toresist transverse tension strains, cross bars of substantially V-shape in cross section connecting the tops of the webs of said T-bars and press welded into the. same with their flat top faces substantially flush with the top edges of the webs, and cementitious fllling in the spaces between the webs of the T-bars and acting to resist compression strains transmitted to the said webs.

14. A grid or grating unit comprising a series of supporting bars located side by side, and a set of cross bars set into the supporting bars and having means at their ends lying alongside the having projecting ends provided with offset anchoring hooks that extend alongside the outermost supporting bar.

17. A grid or grating unit comprising a series of supporting bars located side by side, and a set of cross bars set into the supporting bars, certain of the bars projecting on one side of the unit,

and other bars projecting on the opposite side of the unit.

18. A grid or grating unit comprising a series of supporting bars located side by side, and a set of cross bars set into the supporting bars, certain oi the bars projecting on one side or'the unit and other bars projecting on the opposite side of the unit, the projecting ends of the bars of one unit being adapted to substantially aline with non-projecting ends of the bars of an associated 19. A grid or grating unit comprising a series 01' supporting bars located side by side. and a set of cross bars set into the supporting bars, certain oi the bars projecting on one side of the unit and other bars projecting on the opposite side of the unit, said projecting portions of the bars being provided with anchoring means.

20. A grid or grating unit comprising a series of supporting bars located side by side, and a set of cross bars set into the supporting bars, certain of the bars projecting on one side of the unit and other bars projecting on the opposite side of the unit, said projecting portions of the bars being provided with oflset anchoring hooks.

21. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side by side, cross bars carriedby the supporting bars, the cross bars 01' one unit at one side oif-the sanie alining with certain of the cross bars of the adjacent unit and lapping other cross bars of the adjacent unit.

22. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side by side, cross bars carried by the supporting bars, the cross bars of one unit at one side of the same alining with certain cross bars of the adjacent unit and lapping other cross bars of the adjacent unit, and means for tying the lapped ends together.

23. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side by side, cross bars carried by the supporting bars, and alternately disposed cross bars projecting respectively on opposite sides of the unit, the projecting portions oi the cross bars of one unit extending between the projecting portions of-certain cross bars of an adjacent unit and in substantial line with other of said cross bars.

24. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side by side, cross bars carried by the supporting bars, alternately disposed cross bars projecting respectively on opposite sides of the unit, the projecting portions of the cross bars of one unit extending insubstantial line with certain cross bars 01 an adjacent unit and be-- tween the projecting portions 01' other 01' said cross bars of such adjacent unit, and means for tying together said interposed cross bar portions.

25. A plurality of grid or grating units located side by side, each unit comprising supporting barslocated side by side, cross bars carried by the supporting bars, the cross bars of one unit at one side of the same lapping the cross bars of the adjacent unit and said lapped portions having offset anchoring hooks that lie between the outermost supporting bars of said adjacent units.

26. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side byside, cross bars carried'by the supporting bars, and alternately disposed cross bars projecting respectively onopposite sides of the unit, the projecting portions of the cross bars of one unit extending between the projecting portions of an adjacent unit and said interposed projecting portions having oflset anchoring hooks that lie between the outermost supporting bars of said adjacent units.

27. A plurality of grid or grating units located side by side, each unit comprising supporting bars located side by side, cross bars carried by the supporting bars, and alternately disposed cross bars projecting respectively on opposite sides of the unit, the projecting portions of the cross bars of one unit extending between the projecting portions of an adjacent unit, said interposed projecting portions having ofiset anchoring hooks that lie between the outermost supporting bars of said adjacent units, and a cementitious binder between the units and in which the hooks are embedded.

28. A plurality of grid or grating units located side by side and each comprising flanged supporting bars placed side by side to form a substantially closed base and spaced upstanding webs that produce open-topped channels, cross bars substantially V-shape in cross section embedded and welded in the free margins of the webs with their outer faces substantially flush therewith; said bars alternately projecting beyond the side webs and being formed into downtumed anchoring hooks, the hooks of one unit alternating with those of the next adjacent, and oementitious material filling the channels and extending beneath the cross bars and having the hooks embedded therein, thereby forming a tie between adjoining units.

WALTER F. SCHULZ.