Патент USA US2137009код для вставки
Nov. 15, 1938. J, A. STRQMBERG 2,137,009 CONCRETE STRUCTURE Filed NOV. 27, 1956 5 Sheets-Shea?I 1 ,ggz 1 l0" 99'000 /?" /25000 72‘900 80250 95000 „3'000 2260 @l0/ia 90500 90500 110'000 /33'000 3/20 Zoff. Ípßn/ @W .' l ' C. . . Nov. 15, 1938. J4 A. STROMBERG CONCRETE STRUCTURE Filed NOV. 27, 1936 2,137,009 Nov. 15, 1938. J. A. sTRoMBERG 2,137,009 CONCRETE STRUCTURE Filed Nov. 27, 1936 _ 35W MW l _ _ _ W/ 3 Sheets-Sheet 3 2,137,909 Patented Nov. 15, 1938 UN1TED sTATEs PATENT OFFICE ‘2,131,009 ' coNcnE'rn STRUCTURE' John A. Stromberg, Des Plaines, lll., assignor of one-half to Volcanic Products Corporation, Chicago, Ill., a corporation of Iliinois application November zu, ma, serial No. naait 9 claims. (ci. '1a-_lun` in providing spaced slabs with battered and cor This invention relates generally to improve rugated sides which features together with a ments in concrete'structures and has particular poured bonding element, poured therebetween, reference to light-¿weight concrete floor structures resist the tendency of the slabs to lift in the bending of the joist and also aüord an increase 5 in the moment of inertia in the design. Myinvention contemplates also a novel floor embodying a novel and economical design par 5 ticularly adaptable to use in residences, apart ments and other buildings. ' An object of my invention is to provide a ilre system wherein the precast slabs and precast joists and the poured interlocking bonding ele ments are‘interconnected together by extended l0 reinforcing members. More specifically stated, an important feature resistant and structurally adequate door con struction with the least volume, weight and cost i0 of material, and at a minimum expense of labor; such hoor construction including the novel use, construction and adaptation of precast members affording efilcient methods of manufacture and erection thereof. To meet these basic require of my invention resides in the provision of a floor system having precast joists and precast slabs and a.V poured interlocking bonding element 15 .of precast joists and floor slabs. The floor slabs , wherein for example: l5 ments I provide a novel system or combination ' 4(a) The Joist has a stem or web of minimum being preferably precast. cross-sectional _thickness with a slightly widened Another important feature oi my invention lower flange and an upper flange slightly wider resides in the novel design of the bonding, inter 20 locking and reinforcing details whereby the slabs and joists act integrally or in the manner of a T-section. than the lower ñange. _ Another object of my invention is to produce a tion such as floors for dwellings, the lower flange may 'carry` one or preferably two longitudinally 25 more perfect and eilicient T-beam action between ' 25 the floor slab and joist, that is, to produce a extending reinforcing (tension) bars and the strong and‘rigid joint between the slab and joist sections aiîording a continuous slab. v The lower and upper 20 flanges being reinforced respectively with tension and compression reinforcing members extending longitudinally of the beam. For light construc upper ilange a pair of spaced longitudinally ex - tending‘reinforcing (compression) bars tied to gether with suitably spaced light cross bars. The vertical“ shear reinforcing Aconsists, of suitably 30 In a floor system of the T-section design, the bonding and interlocking element or joint be, 30 tween the >slab and the joist is stressed con spaceclflightr weight stirrups extending vertically intensity for different `design loads and spans.' through: the beam web and having ends looped siderably by shear which obviously varies in unit aroundthe; tension reinforcing. bars in the lower The ultimate shear resistance of such bonding and interlocking element between the slab and -f " flange-arid .intermediate portions or ends extend 35 joist should provide an adequate safety factor "ingaboveïthe top of the beam fadapted to be 35 and should be capable of developing the „yield point strength of the joist reinforcemenhÍ ' ,around ` looped - . the reinforcing bar in the poured ì dink? element. g .l - , The primary object of this invention is'thére->-._ì" ib) `:The'precast‘slabs are formed with down fore directed to the solution of the prcpblerrllof*` ."»Watdlyiputwardly battered opposite sides4 and 40 the bonding joint between the slabs andy-joists ` thebatteredl’isides' are corrugated. The corruga- 40 and to produce a very eñlcient designjet. vfloor v>tionsiextend»transversely of the slab. Each slab ` A'ded with suitable spaced reinforcing bars construction wherein the joist. and slab zfunc-` tion together as a T-section; the design per which xtend outwardly ci or beyond the corru mitting slight variations from exact joistspacing y 45 by the use of spaced slabs and still affording conf.v tinuity and stability of the finished floor slab " _ab-l faces. The ends of these bars are , hooked.v vThe extended portions of these 5 efin' overlapping arrangement over the Another feature of my invention resides’l'inflihe ` l 5015*' “dare-adapted to be embedded Within the system. ' H ï ‘ provision of reinforcing members in the'` slabs 50 and joists which reinforcing membersA 'are pouredï'interlocking bonding section to thereby tie-or interconnect the slabs together through 50 the bonding vjointv element. adapted to extend into a poured or cast-in-place The poured` interlocking or bonding element is bonding element to thereby interlock such bond also preferably -'provided withga longitudinally ing element with the adjacent slabs and sup-` extending reinforcing b_ar around which I loop porting inist. I6 Still another object of my invention resides the outwardly projecting portions of the- vertical 65 stirrups of the beam, thus tieing together .the precast floor slab; It is also a feature of my invention to provide precast concrete beams with a plurality of open ings spaced longitudinally of the beam and ex Fig. 14 is a longitudinal section of the precast floor slab taken on line i4-i4 of Fig. 13; tending through and within the middle one-thrid of Fig. 13; section of the beam length to thereby secure a more effective section by directing and localizing the compressive stresses in the compression sec Fig. 16 is a plan view-of the precast beams ' showing the improved connections between a cross beam or header and between a beam framed into the header; 10 10 tion of the beam above such openings and thus developing more of a truss action rather than a beam action. Another feature of my invention is found in the utilization of such beam openings for pas sages for pipe or conduits and the like. _ Still another object of my invention resides in the provision of a novel fire-resistant connection for precast beam ends which is particularly adaptable for use in framing headers or cross beams into spaced floor beams around stair wells; such connections including rigid steel sad dles secured to the webs of the precast beams and a mass of concrete extending over and around such saddles to substantially cover such 25 steel saddles. With the above and other objects in view, my invention consists in the novel combination, con struction and arrangement of the parts and members shown in preferred embodiment in the 30 attached drawings, described in the following specifications and particularly pointed out in the appended claims. In the drawings: Fig. 1 is a sectional plan view showing a por 35 tion of a floor built in accordance with and em bodying my invention; Fig. 2 is a cross-section taken on line 2-2 of Fig. 1; Figs. 3, 4 and 5, illustrate typical joist sections 40 for dwellings embodying my novel beam design adapted for maximum spans respectively 16 feet, 20 feet and 24 feet; Fig. 6 shows a table giving the approximate cross-sectional areas and weights of the 8, 10 45 and 12 inch joist sections shown in Figs. 3, 4 and 5; Fig. 'l is a table showing the resisting mo ments, steel reinforcing required, and shear val ues for the three illustrated typical beam 50 sections; Fig. 8 shows a typical cross-section of a floor, a ceiling supported on the lower ends of the ioists and manner of~ nmning electric wire conduits through openings in the beam webs; 55 Fig. 13 shows a plan view of atypical concrete beam with the bonding element. Fig. 9 is a side elevation of a typical joist showing spaced openings in the middle one-third section thereof; Fig. 10 is a modified cross-section of a floor wherein the electric wire conduits are run in the plane of spaced floor sleepers between the top wood door and the concrete floor slabs; Fig. 11 is an enlarged cross-section taken on line ii-ii of Fig. 9 showing manner of sup porting the ceiling channels to which suitable wire mesh is secured for a plastered ceiling; Fig. 12 is an enlarged cross-section in per spective taken on line I2-I2 of Fig. 8 showing an opening in the web of the beam, a corrugated 70 side of one of the door slabs and one of its re inforcing cross-bars extended into the space which is to receive _the poured bonding section, and also showing the longitudinal reinforcing bar for the bonding section engaged by a Dair 75 of the spaced beam stirrups; ‘ Fig. 15 is a cross-section taken on line i'l-il Fig. 17 is a cross-section taken on line I1-i`l of Fig. 16; Fig. 18 is a view in perspective showing the metallic saddle adapted to receive the end of a beam. In the concrete floor construction illustrated in Figs. 1 and 2, the walls of a building are in dicated by 2l and the improved precast beams or Joists by 28. 'I‘he precast floor slabs are in dicated by numeral 21. The beam sections shown in Figs. 3, 4 and 5 are illustrative of precast floor Joists made in accordance with my invention for use in struc tures such as dwellings and are intended to sup port precast iloor slabs such as shown for ex ample in Figs. 13, 14 and 15. In my system of floor construction, the beam 28 may be described'as the T-beam type or de sign consisting of an upper flange 26^, a stem or web 28B and preferably a lower flange or 30 widened section 280. The lower section 26° which is under tensile stress is preferably reinforced with two spaced bars 2| extending longitudinally of the beam and the upper section 26A which is under com pression is also preferably reinforced with two spaced bars 29 extendinglongitudinally of the beam. 'I'he reinforcing bars 28 are tied by cross mem bers of heavy wire 30 having ends wrapped or 40 looped around the bars 29. Each beam 26 is reinforced with suitably spaced stirrups 2i consisting of a single wire hav ing an intermediate looped portion 3|^ extend ing about the top of the beam and the ends of . which extend through the stem or web 26B into looped or wrapped engagement sion bars 28 in section 28C. Obviously the size of the wire the spacing of same will vary spacing of and load on the beam. with the ten stirrup 3i and with the size, Í In the typical joist sections illustrated, these stirrups may be, for example, No. 7 wire spaced approximately six inches apart in the outer one-third sections of the beam and twelve inch spacing may be used in the middle one-third section. I prefer to form the precast joists 26 with spaced circular open sections 26D extending through the web 26B. These openings 25D to be within the middle one-third section of the beam 60 length, of a diameter not to exceed one-third of the depth of the beam and spaced approximately two to three times their diameter center to center. The use of these openings not only effects a sav ing of concrete but they form passages for pipe or conduit 32 as illustrated in Fig. 9 and afford a novel beam design of a comparatively effective section wherein the compressive stresses are con centrated or localized in the compression section of the beam above such openings to develop more of a truss action rather than a beam action. Ob viously, these openings might be of other form or configuration as for instance, triangular openings alternately reversedly disposed, that is, the apex of one triangular opening to be pointed toward 75 aisancey the upper flange of the beam and the apex of the adjacent triangular opening to be pointed down wardly toward the lower flange of the beam The upper edge of these openings 26D to be approximately at the meeting line of the face of the web 26B with the angular face of the upper . flange of the beam. The precast concrete floor slab 21 as shown in Figs. 13, 14 and 15 consists of a flat body of mini 10 mum thickness having spaced end and interme diate c_ross ribs 21A each reinforced with a bar 33 which extends at both ends beyond the corru gated sides 21° of the, slab and the ends of which are preferably bent as shown in Fig. 12 for hooked 15 embedment within the bonding and interlocking concrete element indicated by numeral 34 shown in Figs. l and 2. The'longitudinally«extending 3 . header 26W which includes a steel saddle com prising an angle 45 bent U-shape and riveted to a steel plate 48. V'I'he steel saddle is mounted on the side face of the web of the cross-joist or header 28W between the beveled face portion of the upper flange and the lower flange thereof and is secured to the Webby bolts 41 'which are adapted to be embedded in the web. It will be noted that in all of these connections the steel saddle is encased with a block of con 10 crete extending on both sides `and bottom of the U-shaped angle and outwardly to the edge of the outstanding leg of the angle 45 so that the steel saddle is surrounded by a protective casing of concrete indicated by numeral 48. 15 'I'he joist which carries the saddle is cast in each case with a recess 26Y in the upper’flange of sides 21c are of increased cross-section 'and also ` the beam. This recess 26Y extends longitudinally lof »the joist to points slightly beyond the inner reinforced as with bar 35. 20 It will be noted that> the precast floor slabs 21j :faces of the parallel outstanding leg portions of 20 are substantially less in width than the spacing of the precast ioists 26 and that they are sup ported on the joists 26 a spaced distance apart which not only facilitates their installation where such joists might not be exactly spaced, but which slab spacing primarily provides the desir able space for the concrete which is poured at the construction site to constitute the bonding and interlocking element 34. This bonding and 30 interlocking element 34 is reinforced by a longi tudinally extending bar 36 which is engaged within the extended loop ends 3M of the joist stirrups 3|. It will now be readily apparent from the vari 35 ous illustrations that the poured element 34 con stitutes a very important feature of my invention since it interlocks the sides of the slabs with the beams or joists. The reinforcing bar 36 of the `poured element is connected by the stirrups 3i to the beam 26 and the slabs 21 are interlocked with 40 the element 34 not only through the extended hooked reinforcing bars 33 but through the cor rugations in their sides and thus these corruga tions resist the. lateral stresses in the upper flange -of the composite T-beam section which includes 45 the upper portion of the joist 26, adjacent por tions of the slabs 21 and the interlocking bonding element 34. . Fig. 8 illustrates a side elevation of a typical precast floor joist 26 showing the spaced openings the >U--shaped angle 45 and inwardly to the face of the web of the joist. This recess permits the end ofthe joist which is to be supported on the saddle to be lowered into the saddle. It will be noted that the end of each joist, 25 which is to be supported in the saddlefis pro vided with a recess 2BR to clear the encasing con crete of the saddle and that this recess 2BR ex- ~ tends inwardly of the end of the joist and up wardly through the lower flange into a portion 30 of the web of the joist at its plane of support in the saddle. . It may bestated that the distance between the inner faces of the parallel Vertical portions of the outstanding leg of saddle angle is slightly 35 greater than the width or thickness of the web of the joist to be supported therebetween. I claim: ` 1. A reinforced precast concrete T-beam corn prising a flange portion in the compression section 40 thereof, an integral depending stem portion, rein forcing members in said flange portion and in the tension section of said stem portion, and a plu rality of spaced stirrups disposed vertically through said beam, each of said stirrups having 45 an intermediate looped portion disposed above the top of said flange portion and the ends thereof looped about the reinforcing members in the ten sion section of said stem. 2. A reinforced precast concrete T-beam com 50 50 26D in the middle one-third section of the length prising a ilange portion in the compression sec- « of the beam, and in Fig. 9 are shown conduits 32 extending through the joist openings 26D to an outlet box 31 which is supported on the channels 38’which are provided with bent ends 38A hooked 55 for support on the lower flanges 26° of the joists. As clearly shown in Fig. 11 the wire mesh 39 tion thereof, an integral depending stem portion, a pair of spaced reinforcing members extending longitudinally of said flange portion, a plurality of spaced reinforcing cross-members having ends 55 connected to said flange reinforcing members, a for the plaster ceiling 40 is secured to the spaced pair of spaced reinforcing members extending channels 38 by wired connections 4l. An electric longitudinally of the beam in the tension section of said stem portion, and a plurality of spaced light fixture is indicated by 42. In Fig. 10 the conduits 32 and the outlet box stirrups disposed vertically through said beam, 31 are disposed in the plane of the spaced wood sleepers 43 between the wood floor 44 and the top of the precast slabs 21. Figs. 16, 17 and 18 illustrate my improved fire resistant connection for inter-framing of joists with cross-joists as for instance, around floor openings or stair wells. In these illustrations 26X indicates a pair of joists supporting a crosse 70 joist or header 26W into which is framed the in termediate joist 262. ' _ The fire-resistant connections for the ends of the header 26W and the end of joist 26z are simi# lar and it will therefore sumce to describe the 75 connection between the end of joist 26Z and 60 each of said stirrups having an intermediate looped portion disposed above the top of sa'id flange portion and each end thereof looped about .one of said stem reinforcing members. 3. A precast concrete beam as embodied in 65 claim 2 wherein said stem includes a plurality of spaced circular openings within the middle one-third section of the length of the beam, said openings being substantially of a diameter not exceeding one-third of the depth of the beam and 70 being spaced substantially a distance of two to three diameters center to center. 4. A reinforced concrete beam comprising an upper flange portion in the compression section thereof, a lower flange portion of comparatively - 75 4 , 9,187,000 decreased cross-sectional width, a web formed in tegrally with said flange portions of a cross-sec tional width less than that of said lower flange, a plurality oi' spaced reinforcing members extend ing longitudinally of each of said flanges, a plu rality of spaced reinforcing cross-members con necting the reinforcing members in the upper iiange, and a plurality of spaced stirrups disposed vertically through said upper flange and web, lo each of said stirrups having an intermediate .looped portion extending above the top of said beam and the ends thereof in looped engagement with the reinforcing members in the lower flange, said upper flange being formed with a pair of 15 longitudinally extending triangular sections cast integrally with the upper flange and the web con stituting a stiifening Junction for theseportions. 5. A reinforced precast concrete beam as em bodied in claim 4. and including a plurality of spaced openings extending through said web, said openings being disposed within substantially the middle one-third section of the length of the beam to localize the compression stresses in the rein !orcedconcrete section above said openings. 6. A reinforced precast concrete beam as em- l bodied in claim 4, and including a plurality of spaced circular openings extending through said web. said circular openings being located within substantially the middle one-third section of the length of the beam and substantially of a diam eter not exceeding one-third of the depth of the beam and spaced substantially a distance of two to three diameters center to center. l7. A light weight concrete floor structure of minimum weight comprising a plurality of spaced reinforced precast concrete joists of T~beam sec tion. a plurality of reinforced precast concrete slabs of minimum cross-section «having spaced cross-ribs with a reinforcing member in each of said >cross-ribs extended at its ends beyond the sidesof the slab, said slabs being arranged in spaced rows.A for support on said joists in such manner as to leave a channel therebetween over the center of said joists and having downwardly 45 outwardly battered corrugated side faces defining said channels, a pair of spaced longitudinal rein-> forcing members in the compression and tension sections of each of said joists, a plurality of spaced reinforcing stirrups extending vertically- of said Joistsihaving intermediate looped portions ex tended above the top of said Joists into said chan~ nels, a concrete bonding and interlocking element poured into said channels flush with the top of said slabs, and a reinforcing member extending longitudinally within said poured concrete ele ment and disposed within said looped portions of said stirrups. > 10 8. A concrete floor structure comprising a plu rality of spaced reinforced precast concrete T beam ioists, a plurality of reinforced precast concrete slabs supported in spaced rows on the flanges of said T-beam ,ioists so as to leave a chan 15 nel over the center of said joists between adjacent sides of said slabs, transverse reinforcing mem-4 bers in said slabs having ends thereof extended into said channels, spaced reinforcing stirrups in said joists having looped portions extending 20 above said joists into said channels, a concrete bonding and interlocking element poured into said channels flush with vthe top of said slabs, and a reinforcing member extending longitudi nally within said poured concrete bonding ele 25, ment disposed within said looped portions of said stirrups whereby adJacent portions of said slabs increase the effective compression flange section of the joists, said slabs having corrugated sides defining said channels for said poured concrete. 30 9. A comparatively light weight reinforced pre cast concrete floor slab having a body with a smooth level upper face. said body being of mini mum cross-section with spaced end and inter mediate integral cross-ribs formed on the lower 35 face of said body, said cross-ribs merging with longitudinal ribs formed on the lower face of vthe body at the sides of the slab and having down wardly battered and transversely corrugated outer faces, a reinforcing rod in each of said cross ribs, and a reinforcing rod in each of said longi tudinal side ribs, -said cross-rib, reinforcing rods having ends extended beyond the corrugated side faces and bent for interlocking engagement with in a poured concrete bonding element between 45 spaced rows of such slabs. y JOHN A. S'I'ROMBERG.