USRE23074E - Pkecast concrete corrugated - Google Patents

Description

Jam 11, 1949. HENDERSQN Re@ 233074 PREGAST CONGHEUAE CORRG'HEED GENNEGTIQN Qmgin'al Filed May 12. 1945 -4 sheets-sheet, 1

a1 20\J0, 1.316519 -Zilg 2 INVENTOR Jan.- 11, 1949. A. HENDERSON PRECAST CONCRETE COIRRUGATEDI CONNECTION 4 Sheets-Sheet 2 Original Filed May l2. 1945 llVENTO R Awe/" Henderson A Jan. 1l, 1949,;` A. HENDERSON: Re- 23,074

PRECAST CONCRETE CORRUGATED CONNECTION 4 Sheets-Sheet 3 original Filed May 12,1945

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Jan. 11v v1949. A. HENDERSON l PRECAST CONCRETE CORRUGATED CONNECTION 4 Sheet's-Sheet 4 original Filed May 12, 1945' Reissued Jan. 1.1, 11949 PRECAST CONCRETE CORRUGATED CONNECTION Albert Henderson, Pittsburgh, Pa., assigner, by

mesne assignments, to The Cemenstone Corporation, Pennsylvania Pittsburgh, Pa.,

a corporation of Original No. 2,414,738, dated January 21, 1947, Se-

rial No. 593,375, May 12, 1945. Application for reissue January 14, 1948, Serial No. 2,186

(Cl. Y2-106) 10 Claims. 1

This invention relates to building construction and, in particular, to connections whereby pre-- cast concrete members may be assembled in the course of erecting a building.

The use of precast concrete members in building construction was first proposed many years ago but has not achieved very wide acceptance. I believe this is due principally to the lack of satisfactory means for securing together various types of members, i. e., columns, girders, beams, etc. I have invented a novel system of connections for precast members having the ability to transmit shear stress from one member to an.- other with high efficiency. In a preferred embodiment, my connections comprise coacting surfaces on the members to be connected having similar corrugated surfaces. The corrugations on the adacent surfaces may actually mesh or interft with each other or may be spaced apart with a grout filling in the intervening space. Where the corrugations mesh with each other, a thin layer of grout is preferably disposed thereon before the surfaces are abutted. My invention also contemplates the use of bolts in making certain types of connections, and I provide a connecting bolt having a protective cap of concrete cast on the head thereof as Well as a nut of similar construction and a separate cover adapted to be disposed over a nut after it has been turned down on a bolt.

Precast corrugated connections, according to my invention may take a variety of forms, some of which are illustrated in the accompanying drawings and will be described in detail hereinafter. In the drawings,

Figure 1 is a partial plan view of a girder having supporting brackets attached thereto adapted to receive the ends of beams;

Figure 2 is a section taken along the plane of line II-II of Figure 1.

Figure 3 is a partial section through the meeting surfaces of adjacent members spaced slightly apart, showing a modified form oi corrugation adapted to provide a connection therebetween;

Figure 4 is a diagram illustrating the dimensionng oi the corrugations;

Figure 5 is a view similar to Figure 3 showing a reinforced corrugation;

Figure 6 is a partial section through a precast concrete member and a support therefor showing a corrugated connection therebetween;

Figure 7 is a view similar to Figure 1 showing a modied construction;

'Figure 8 is a section taken along the plane of line VIII- VIII of Figure 7;

Figure 9 is a partial side elevation of a supporting bracket used in the construction illustrated in Figures 7 and 8;

Figure 10 is a partial elevation showing a modied form of connection between a column and girder;

Figure 11 is an axial section through a precast concrete nut cover;

Figure l2 is a similar View showing a nut embedded in a precast cover;

Figure 13 is a similar view showing a protective cap cast on the head of a bolt;

Figure 14 is a plan view of a column of H-section having a pair of brackets associated therewith forming a shelf adapted to support a girder or the like;

Figure 15 is an elevation oi one of the brackets;

Figure 16 is a section through a precast member showing in elevation a sleeve connecting two similar members end-to-end;

Figure 17 is a section taken along the plane of line XVII- XVII of Figure 16;

Figure 18 is a partial plan view of a modified form of connection between members disposed end-to-end;

Figure 19 is a transverse section taken along the plane of line XIX- XIX of Figure 18;

Figure 20 is a partial section taken centrally through a precast connecting sleeve adapted to connect precast members of different sizes endto-end;

Figure 21 is a partial elevation of a column showing integral and separately formed shelf brackets adapted to receive the ends of adjacent f members;

Figure 22 is an elevation with parts in section showing a different form of bracket adapted to be secured to a column for supporting a beam;

Figure 23 is a partial elevation showing a corrugated connection between it and a beam supported thereon and also a different form of supporting bracket adapted to receive a beam;

Figure 24 is an elevation of a column secured to a separately formed base by corrugated connections and provided with a bracket for supporting a beam and a connection to a superposed eolumn oi smaller sectional area; and

Figure 25 is a section through a one-piece co1- lar having a corrugated connection to a column shown in elevation.

Figures 1 and 2 illustrate a connection between a girder I0 and a beam ll. Precast brackets l2 are secured to the girder by a through bolt I3. Pipe lengths i4 and I5 are embedded in the girder and brackets to accommodate the bolt. Instead of through bolt I3 I may use two separate bolts and embed nuts in the girder I to receive them. These nuts should be threaded on suitable anchor rods embedded in the girder. The sides of the girder are corrugated as at I6 and the contacting faces of the brackets have corrugations I1 meshing therewith. A thin layer of grout is applied between the contacting surfaces of the girder and brackets.

The brackets have pockets I8 formed therein adapted to accommodate the ends of beams, such as that indicated at The inner surfaces of the sides and end of the pockets are corrugated and the end portions of the beams I I are similarly corrugated on both the sides and extreme end thereof. The maximum width of the beam II, i. e., the width from crest to crest of the corrugations, ,is less than the minimum width of the pocket I8, i. e., from crest to crest of the corrugations, so that the end of the beam may be moved longitudinally into the pocket. It may also, of course, be set therein from above. In any event, the corrugations of the two members do not mesh but are spaced apart. The space I9 between the beam and the bracket is filled with grout. When the grout has set, the corrugations in the sides of the pockets and on the sides of the beam prevent the beam from pulling out of the bracket, The corrugations on the inner end of the pocket and on the extreme end of the beam, being locked against relative vertical movement by the grout, transmit shear from the beam to the bracket. A similar transmission from the bracket to the girder is effected by the meshing corrugations on the contacting surfaces thereof. The girder and brackets have reinforcing members embedded therein as indicated at 20 and 2|. The beam II may be similarly reinforced.

Figure 3 shows corrugated surfaces of members 22 and 23 to be connected, the corrugated surfaces being provided with metallic armor in the form of plates 24 and 25 having tongues 24a and 25a struck up therefrom and embedded in the members 22 and 23. In addition, double nuts 26 welded to the upper and lower ends of the armor 24 have anchor bolts 21 threaded therein `and embedded in the member 22. Holes 28 in the upper and lower ends of armor 25 permit the member 23, which may be a beam, to be secured to the member 22, which may be a column, by suitable screws. The armored type of connection shown in Figure 3 makes grout unnecessary and exhibits a very high efliciency in transmitting shear load.

Figure 4 illustrates the corrugations in the surfaces of the various members to enlarged scale. These corrugations are preferably `so proportioned that the pitch p is equal to twice the depth d. In other words, the sloping faces of the corrugations make 45 angles with the surfaces of the members in which they are formed.

The relation of the pitch and depth may be expressed mathematically as p=2d. The pitch is preferably 1" and the depth l" so that members of standard dimensions, such as 8" x 8, 8 X 10, 12"' x 12, 12" x 14, etc., Will have an even number of corrugations across their vertical or horizontal faces.

Figure shows reinforced corrugations formed in members 29 and 30 adapted to be connected, e. g., a column and beam, respectively. As illustrated, the member 29 has spaced fiat bars 3| and the member 30 similar bars 32 embedded therein with their edges centered on the crests of 4 the corrugations and projecting to the extremity thereof. The at bars 3| and 32 may be welded to round spacer bars 33 and 34 embedded in the members.' Since the edges of the bars 3| and 32 are exposed at the crests of the corrugations, the roots are flat to conform therewith.

Figure 6 shows a member 35 having a pocket 36 therein adapted to receive the end of a member 31. The member 35 may be a column base and the member 31 a column, The sides of the pocket 36 are corrugated and also the sides of the member 31 to the depth of the pocket. The dimensions of the member 31 are related to those of the pocket 36 in the same manner as those of the end of the beam II to the pocket I8 in bracket I2. Thus the end of the member 31 may be set in the pocket 36 and the space 38 therebetween filled with grout. This provides a permanent connection between the members capable of transmitting shear stress almost to the full strength of a monolithic structure of similar shape and dimensions. It will be understood that all four sides of the member 31 and all four sides of the pocket 36 have corrugations formed therein.

Figures 'I and 8 illustrate a modied form of connection comprising a saddle bracket 39 adapted to be placed on a girder 4Ul for supporting beams 4| thereon. The bracket is generally yoke shaped and has reinforcing rods 42 embedded therein. The sides of the girder are corrugated at 43 and the inner surfaces of the depending sides of the bracket are similarly corrugated as at 44, the space between the corrugations being filled with grout. Positioning pins 45 are embedded in the girder and project upwardly therefrom. The bracket has pipe lengths 46 embedded therein and welded to the reinforcing bars 42 for accommodating the pins 45. Vertical keying grooves 41 are lled with grout to prevent shifting of the bracket,

The bracket has shelves 48 with pockets 49 formed therein adapted to receive the ends of beams 4|. Securing pins 50 disposed in slots 5| in the ends of beams 4| and in recesses 52 in the sides of the pockets tie the beams to the bracket. In the case of end girders, brackets vcorresponding to one-half the bracket 39 may be employed.

Figure 10 shows a modified corrugated connection between a support, such as a column 53 of H-section, for example, and a beam 54 of similar section. The column ange and the end of the beam have interfitting corrugations 55 and 56. These corrugations have one sloping side and one horizontal side. Anchor bolts 51 embedded in the beam extend through holes in the column flange and are secured thereto by nuts. The corrugations 55 and 56, like those previously described, are l wide and 1/2 deep. The corrugated surfaces are preferably grouted before the connection is made. It will be apparent that the connection shown in Figure 1U does not require a supporting shelf or bracket.

Figure 11 shows a precast reinforced nut cover 58 having a threaded socket 59 therein to accommodate the end of a bolt, The cover 58 is preferably placed on a nut after the latter has been turned down and the threads of the pocket 59 are engaged with the threaded end of the bolt protruding beyond the nut. The cavity 6|) in the cover is cylindrical and of such size as to permit the cap to turn on the nut.

Figure 12 shows a nut 6| having a cover 62 cast thereon. The nut is preferably welded to a reinforcing member 63 having wings 63a extending outwardly therefroml and embedded in the cony creto forming the cover. This type of nut may be turned down on a bolt by a suitabl-e wrench vapplied to the exterior of the cover.

Figure 13 shows a bolt 64 having 'a cover 65 cast on the head thereof. A reinforcing member 86 similar to that shown at 83 is welded to the lower face of the head.

The nut covers shown in Figures 1.1 and 12 and the bolt-head cover of Figure 13 make the connections requiring bolts and nuts weatherproof and reproof.

Figures 14 and 15 illustrate a bracket composed of two similar 'members 61 adapted to engage a flange of an H-sh'aped member G8 such as a column. The inner faces of vthe members 61 are recessed as at 69 to accommodate the flanges of the column. Anchor `bolts extend upwardly 'above the top face of the brackets and are adapted to enter holes in -a beamer g'i-Ider placed thereon. The bracket membersare thus secured together. They are also grouted to the column as shown at 1 I. The flanges engaged by the bracket members are corrugated horizontally as at 12 and the inner faces of the bracket members are similarly corrugated as at 13 so that the shear load applied to the bracket members is transmitted to the column. Grooves 14 in the adjacent faces of the bracket members Aand column flanges aid in preventing separation of the bracket members from the column.

Figures 16 and 17 illustrate a one-piece connecting sleeve adapted to connect two members 18 and 11 end-to-end. The sleeve 15 is precast and reinforced. It has corrugations 18 extending around the interior. The abutting ends of the members 16 and 11 have similar corrugations 18. When the members have been asse-mbled, as illustrated, the intervening space is filled with grout as indicated at 80.

' Figures 18 and 19 show a modified connection between members 8| and 82 disposed end-to-end. Precast reinforced splice plates 03 are Adisposed on opposite sides of the members 8| and 82 and secured thereto by through bolts 84. Pipe lengths 84a and 84h are embedded in the members 'and splice plates to accommodate the bolts, and 'may be welded to the reinforcing in the members and splice plates, respectively. vThe pipe lengths 84a have anchor bars 84e welded thereto and embedded in the vmember-s. Links 84d embedded in the .splice plates provide connections between the bolts through adjacent members. The links `ex'- tend around the pipe lengths 84o. The heads of the bolts and the nuts turned on the threaded ends thereof fit into sockets 85 in the splice plates which are filled with grout after the nuts have been turned home, thus making the joint vfire-- proof and corrosionproof. The contacting sur'- faces 'of the plates B3 and members 8| and -82 have meshing corrugations 86 'formed therein. A thin layer of grout may be applied thereto before the members are assembled and finally secured together.

The aggregate section of reinforcing rods in the splice plates is equal to that in either one of the members 8| and '82. The connection between the latter thus has practically the full strength of either member.

Figure 20 illustrates a precastconnecting sleeve 81 adapted to unite precast .members 88 yand -89 of different cross sectional areas. The `sleeve l|31 and the members 88 and 88 are precast and reinforced. The sleeve 01 has a socket 90 adapted to receive the end of :member 88 vand a 'socket `8| adapted to receive the end of member 89. The

6 side walls of the .sockets are corrugated -as at '92 and the ends of the members. 88 and 89 as at S3. The sizes of the sockets are such as to permit the members 88 and 89 to enter freely therein. When the members have been assembled With the sleeve, the spa-ce therebetween is filled with grout vas at 94. Holes 95 through the sides of the sleeve communicating with the sockets facilitate the grout-lling operation.

Figure 2l shows further forms of connections between a member 90 of H-shape, such as a column, and a member supported thereon, such as a beam S1. A bracket 98 formed integral with the column .has its upper surface corrugated as at 99. The column flanges are corrugated above 'the bracket as at |08. The end and bottom of the beam 91 have corrugations meshing with those indicated at 98 and |00, a thin layer of grout being applied over the contacting surfaces beforethey are put together.

Gn the other side of the beam, a separately formed bracket |0I is attached thereto by bolts |02. The outer faces of the adjacent flanges of the member 9B are corrugated as at |03 and the vertical face of the bracket has corrugations |04 meshing therewith, a thin layer of grout being applied therebetween. The bracket |0| has a double nut |05 embedded therein. The nut is threaded on an anchor boltl |06 and is adapted to receive a bolt inserted through a hole in a beam resting on the bracket for securing'it thereto. As shown, the corrugations |03 extend above the bracket |0 I. The beam supported on the bracket may thus have its end corrugated as shown at |08 on the beam 01. By this construction, a portion of the shear load 'on the beams is transmitted directly to the column, the remainder 'being borne by the brackets. In the `case of the bracket 98, corrugations on the upper face thereof prevent the beam from pulling away from the column.

Figure 22 shows a further modified form of bracket I 01 secured to a support such as an H- vshaped column |08 by bolts |09 inserted through holes in the flanges of the latter. The bolts are threaded into nuts IIE) embedded in the bracket which is precast and reinforced. The bolts |09 have covers 65 on the heads thereof. The contacting surfaces of the bracket and lcolumn have meshing corrugations I. The .bracket |01 has a socket ||2 formed therein adapted to receive the end of a beam |I3 which is illustrated as of H- shape in section. The Walls of the socket I2 and the end of the beam I|3 have meshing corrugations H4. vThe beam and bracket are assembled by sidewise sliding movement of one relative to the other after a thin lm of grout has been. applied to the contacting surfaces. corrugations .I I have Va similar lm of grout applied thereover. The nuts H0 are welded to reinforcing rods H5 embedded in the bracket.

Figure l23 illustrates a still further form of connection between a support such as a'column IIS and a precast member supported thereon such as a beam ||1. In the embodiment illustrated, the kcolumn and beam are of H-shape in section. The beam ||1 is secured to the column by bolts I8 inserted through holes in the column flanges and threaded into double nuts embedded Ain the beam as illustrated at 26 in Figure 3. The contacting surfaces of the beam and column have meshing corrugations |20 formed therein. A thin film of grout is applied over these surfaces rbefore fthe members are connected. 'Ihe corruga- The i tions serve to transmit the shear load on the beam `to the column as already explained. The web of the column may have ycorrugations |2| to receive a beam extending at right angles to the beam ||1.

On the other side of the beam IIE, a precast reinforced bracket |22 is secured by bolts |23 similar to the bolts I I8. The contacting surfaces of the bracket and column have meshing corrugations |24 to which a thin film of grout is applied before the bracket is secured in place. The bracket has upper and lower shelves |22a and |22b. Bolts |25 extend through the latter and through holes in the flanges of a member |26, such as a beam of H-shape in section. The end of the beam is received between the shelves of the bracket, -a thin layer of grout |21 being applid therebetween.

Figure 24 illustrates several forms of connections adapted particularly for precast columns. A precast column base |28 is secured to a fieldcast footer |29 by bolts |30 which may either be anchor bolts embedded in the footer or separate bolts threaded into double nuts, such as shown at 26 and ||0, embedded therein. The base |28 has spaced upstanding walls |3| adapted to receive the lower end of a column |32 therebetween. The column is illustrated as of H-shape in section. The outer surfaces of the column flanges and the inner surfaces of the walls |3| of the base have meshing corrugations |33 formed therein. The column and base are assembled in the same manner as the beam ||3 and bracket |01, i. e., by relative lateral movement, after the corrugations have been properly lined up. A thin film of grout is applied over the contacting surfaces. A layer of grout |34 is applied between the bottom of the column and the base to transmit to the base at least a portion of the load on the column, the remainder being transmitted through the corrugations |33.

A collar bracket |35 is disposed on the column at an appropriate height for supportingv horizontal members such as girders or beams. The bracket is precast and reinforced. It is applied by placing it over the upper end of the column and moving it vertically therealong into proper position. The inside dimensions of the collar are suiiicient to permit free movement thereof on the column. Meshing corrugations |36 are formed on one interior face of the collar and on one side of the column at the height at which the collar is to be fixed. When the collar has been placed at the proper height, it is moved laterally to cause meshing engagement of the corrugations. Thereafter, the clearance space between the bracket and column is lled with grout as at |31. The bracket |35 has upper and lower shelves |35a and |3511 similar to those of bracket |22.

A cap |38 is disposed on top of the column |32. It is similar to the base 3| and has grout applied between its corrugations |39 meshing with those formed at the upper end of the column. A layer of grout |40 is applied to the top of the column before the cap is placed.

A base |4| is placed on the cap |38 with a layer of grout |42 therebetween and secured thereon by bolts |43 inserted through alined holes in the cap and base. The base |4| is similar to that shown at 3| except that its side walls |44 are adapted to accommodate a column |45 somewhat smaller than the column |32. The base |44 and the column |45 are united in the same manner as the base |28 and column |32 by meshing corrugations with grout applied as previously eX- plained.

Figure 25 illustrates a precast reinforced concrete bracket |46 mounted on a column |41. The bracket has corrugations |48 on opposite interior walls. 'The column has corrugations |49 on the outer faces of its flanges. When the bracket has been positioned as illustrated, the spa-ce between it and the column is filled with grout as at |50. The inside dimensions of the collar are such as to permit free movement thereof along the column. The bracket has upper and lower shelves |46a, and |45b on opposite sides thereof adapted to receive the ends of beams such as that shown at |5|. Bolts |52 inserted through holes in the bracket shelves and beam flanges secure the beam to the bracket. The beam and column as illustrated are of H-shape in section. The bolts may have protective covers on the heads thereof as illustrated in Figure 13.

It will be apparent that my invention provides a novel set of connections adapted for uniting various types of precast concrete structural members useful in the construction of buildings. The principal advantage of the several forms of connection is that they all have the ability totransmit shear load with a high degree of efficiency. This load is transmitted, furthermore, through the .adjacent surfaces of the several members and not through the tie means where such are employed. The formation of corrugated surfaces on the various members is a simple matter, involving only the use of molds or cores having appropriately shaped surfaces. The precast nut and bolt covers afford protection for the tie means against corrosion and fire.

Although I have illustrated several forms of connection embodying my invention, it will be understood that changes in the details thereof as illustrated may be made without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. A structural connection comprising a precast concrete support member, a second precast concrete member supported thereon, said support member having corrugations formed in a lateral face thereof, and said second member having corrugations formed in the place thereof adjacent the corrugated face of the support member, the corrugations of the second member meshing with the corrugations of said support member, and means for reinforcing said corrugations in said members including metal plates embedded therein.

2. A structural connection as dened by claim 1 ycharacterized by metal members embedded in said support member and welded to the plates embedded in the corrugations in said support member, and metal members embedded in said second member and welded to the plates embedded in the corrugations thereof.

3. A structural connection comprising a precast concrete support member and a precast concrete bracket member secured to said support member, said bracket member having a pocket therein, said pocket having substantially verticalspaced side walls and an end Wall, and corrugations formed in said spaced side walls land said end wall, the corrugations in the end wall being transverse to the corrugations in said spaced side walls.

4. A structural connection as defined by claim 3 characterized by corrugations formed in a face of said support member and corrugations formed in a face of said bracket member meshing with said first-mentioned corrugations.

5. A structural connection as defined by claim 3 characterized by a beam member having one end disposed in said pocket, the end portion of said beam member resting in said pocket having corrugations formed on the vertical sides thereof and a grout lling between the corrugations in said pocket and those of said Ibeam member.

6. A structural connection comprising a precast concrete support member having a bracket secured thereto and a precast concrete beam member having one end supported on said bracket, substantially horizontal corrugations formed in the top of said bracket and corrugations meshing therewith formed in the bottom of said beam, substantially horizontal corrugations formed in the support member above the bracket, and corrugations meshing therewith formed in the end of said beam.

7. A structural connection comprising a precast concrete support member, a precast concrete bracket member thereon, said support member having substantially horizontal corrugations formed in a surface thereof, said bracket member having corrugations formed in one of its surfaces meshing with the corrugations of said support member, a beam member resting on said bracket, and a tie securing said beam on said bracket.

8. A structural connection comprising a precast concrete support member, a precast concrete collar bracket surrounding said support member, substantially horizontal corrugations formed in a surface of said support member and substantially horizontal corrugations formed in an interior face of said collar bracket, and a grout lling disposed between the corrugations in said support member and the corrugations in said collar member.

9. A structural connection comprising a precast concrete support member, a precast concrete saddle bracket member straddling said support member, said support member having substantially horizontal corrugations formed on opposite faces thereof and corrngations formed in the inner faces of said saddle bracket coacting with said corrugations in said support member.

10. In a building construction, a static concrete structure comprising a precast concrete support member, a precast concrete bracket member carried by the support member and another member bearing against the bracket member and normally exerting force thereagainst tending to shear the bracket member from the support member, the support member and the bracket member having opposed faces through which they 'bear against each other, said faces having intertting corrugations extending transversely of the direction of said force,

ALBERT HENDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 967,007 Fogg Aug. 9, 1910 1,538,218 Seelye May 19, 1925 2,094,167 Evers Sept. 23, 1937

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