US3914915A - Reinforcing mat structure for planar concrete construction units - Google Patents

Reinforcing mat structure for planar concrete construction units Download PDF

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Publication number
US3914915A
US3914915A US881821A US88182169A US3914915A US 3914915 A US3914915 A US 3914915A US 881821 A US881821 A US 881821A US 88182169 A US88182169 A US 88182169A US 3914915 A US3914915 A US 3914915A
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United States
Prior art keywords
section
mats
mat
strips
infrastructure
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Expired - Lifetime
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US881821A
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English (en)
Inventor
Schyndel Andreas Van
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Baustahlgewebe GmbH
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Baustahlgewebe GmbH
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    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04C—STRUCTURAL ELEMENTS; BUILDING MATERIALS
    • E04C5/00—Reinforcing elements, e.g. for concrete; Auxiliary elements therefor
    • E04C5/01—Reinforcing elements of metal, e.g. with non-structural coatings
    • E04C5/02—Reinforcing elements of metal, e.g. with non-structural coatings of low bending resistance
    • E04C5/04—Mats

Definitions

  • a composite reinforcing mat structure for use in planar construction units comprises an infrastructure composed of a plurality of unit mats each consisting of two sets of intersecting longitudinal and transverse bars connected at their intersection points, said mats arranged with adjoining marginal longitudinal zones overlapping each other, and a multiplicity of mat strips each consisting of at least two longitudinal bars connected by transverse bars and overlying said infrastructure in predetermined spaced relation to [56] References Cited each other and to the median lines of the overlap UNITED STATES PATENTS zones of said structure.
  • the present invention relates to reinforcing arrangements for planar concrete construction units or slabs, more particularly of the type comprising a plurality of juxtaposed and mutually overlapping unit steel mats each composed of two sets of rectangularly intersecting longitudinal and transverse bars connected at the intersection points, preferably by spot welding.
  • Planar concrete construction units such as ceiling slabs or plates, may be reinforced either by the use of single steel bars or by the aid of prefabricated reinforcing steel mats.
  • single bars it is possible to realize the required metal cross-section of the reinforcement as derived from static analysis in all the variety required and with any desired degree of accuracy.
  • any construction unit may be reinforced adequately from both a static and constructional point of view. Reinforcement by means of single bars has however the disadvantage of a considerable expenditure of labor, because each bar must be prepared and assembled separately.
  • the second possibility of reinforcing planar concrete constructions units consists in the use of prefabricated reinforcing mats. These mats consist of two sets of rectangularly intersecting longitudinal bars and transverse bars connected at the intersection points, preferably by electric spot welding. For reasons connected with the fabrication and transport of such mats, they cannot be provided in any desired sizes or dimensions. in order to achieve the desired reinforcement of a given construction unit, the mats must be superimposed with the marginal overlap zones or regions being such as to enable an adequate load or force transmission from one mat to the next. This overlap is sometimes referred to as the thrust of the mats in the composite structure or assembly. i
  • the advantage of the foregoing type of reinforcement is due to the fact that large surface reinforcing units may be realized practically and economically, as well as to relatively close specifications and tolerances. Since the separate operations involved in the use ofindividual bars, such as bending, correct laying and connections of the bars, are dispensed with by the use of prefabricated mat units, the mats can be layed or assembled expeditiously as well as securely. The rigid connection of the longitudinal and transverse bars by the spot welding joints has the further result of an intimate adherence of the reinforcement for the concrete.
  • the aforementioned advantages of the reinforcement by means of unit mat involves a certain rigidity of the system or assemblage.
  • the metal cross-section per unit length of the longitudinal and transverse bars must be fixed for the prefabrication, both with regard to the distances of the individual bars from each other as well as in regard to the available rod or bar diameters.
  • the bar diameters offered by the steel or wiring industry there has been evolved during the course of the years a certain standardization to the effect that only distances of 50 mm and multiples thereof and 75 mm and multiples thereof are being used in practice.
  • the choice of the distances is further limited by the fact that load-supporting bars should have a distance not exceeding 200 mm and transverse bars a distance not exceeding 333 mm from each other.
  • the cross-section of the longitudinal bars within the marginal or overlap zones isone-half of the cross-section of the bars within the remaining or intermediate zones of the mats. in this manner, it has become possible to achieve a substantially uniform metal cross-section distribution per unit width throughout the entire range or width of the composite mat structure.
  • an important general object of the present invention is the provision of means and a novel multiple reinforcing mat structure combining the advantages of the prefabricated unit mats with the flexibility and advantages of the reinforcement by means of individual bars, substantially without involving the drawbacks and disadvantages of either method or system of concret slab reinforcement.
  • the invention in volves generally the superposition upon a multiple mat arrangement composed of conventional unit mats, forming an infrastructure and providing a first basic reinforcement for the concrete part or slab to be reinforced, of a multiplicity of secondary mat units in the form 'of narrow mat strips each consisting of at least two longitudinal bars connected by transverse bars, said strips being distributed over said structure at such spacing distances from each otheprafid from the median lines of the overlap zones of said structure as to cause the ensuing consecutive local metal cross-section accumulations to be substantially uniformly distributed across said structure and to be effectively added in their resultant action to the basic reinforcement provided by said infrastructure, to thereby result in a final desired total reinforcement of the concrete slab or the like construction unit to be reinforced.
  • the basic reinforcement may be in the form of multiple or unit mats having longitudinal bars of constant cross-section across the entire width of the mats.
  • the metal cross-section provided by the additional mat strips advantageously equals the excess cross-section in the overlap zones and the mat strips are distributed at equal distances from each other and said zones across the entire mat or infrastructure.
  • the metal cross-section provided by the mat strips advantageously equals the cross-section within the overlap zones and the strips are distributed at fixed distances from each other, on the one hand, and at half said distances from the overlap zones, on the other hand.
  • a pair of sets of narrow mat strips intersecting one another may be provided oriented with the respective supporting axes of the slab or part to be reinforced. In many cases it is sufficient to provide a limited number of transverse bars for the additional mat strips to serve as means to secure the positions of the strips.
  • the small additional mat strips may be of reduced length conforming with the prevailing bending movement effective on the slab, and/or the strips may be bent upwardly towards the upper face of the slab or the like planar part to be reinforced.
  • the advantage of the reinforcing arrangement of the invention is to be seen primarily in the fact that the mats disposed in the lower layer (infrastructure) serve to provide the cross-section for the basic reinforcement which must extend from one abutment of the construction part to the other, while the upper layer formed by the second units or narrow mat strips serves to achieve the final metal cross-section or distribution.
  • the second layer composed of small mat strips it is possible, depending upon the number and distance of the strips, to realize a multiplicity of reinforcing crosssections up to double the cross-section of the first layer ofinfra-structure composed ofa single type of unit mat.
  • the same metal cross-section range may be realized by six conventional mat types in conjunction with five mat strip types according to the invention.
  • six mat units and five mat strips which may be distributed for instance at distances of 1.0; 0.90; 0.80; 0.70; 0.60; and 0.50 m across the entire reinforcing width, it is possible to realize 6 6X5 different metal cross-sections.
  • a further advantage of a combination according to the invention comprising a basic reinforcement (infrastructure) composed of conventional unit mats, on the one hand, and additional mat strips, on the other hand, is due to the fact that the additional strips may, in the manner heretofore customary with many reinforcements, be cut short at a region of tensile stress, enabling thereby a reduction in length of the strips in conformity with the prevailing bending moments affecting the slab to be reinforced, on the one hand, and that, as has been heretofore possible only with single bar reinforcements, the strips may be bent upwardly towards the top face of the slab or the like planar construction unit.
  • a further problem resides in the fact that, depending upon whether the part to be reinforced is to be supported in a single or two axes, different degrees of reinforcement by the transverse bars are required.
  • the minimum transverse reinforcement in case of parts stressed in a single axis is of the metal crosssection of the supporting or longitudinal bars.
  • different mat types may be provided containing approximately 40, 60, 80 and 100% of the corresponding cross-section of the longitudinal bars. In this manner, the number of mat types to be stockpiled may be further reduced.
  • FIG. 1 is a fragmentary cross-sectional view through a known composite reinforcing mat structure composed of uniform unit mats, resulting in an excess metal cross-section within the overlap zones;
  • FIG. 2 is a sectional view similar to FIG. 1, showing a composite mat structure made of unit mats designed to result in a uniform metal cross-section distribution across the width of said structure;
  • FIGS. 3a 3f illustrate cross-sections of mat strips suitable for use in accordance with the improvement by the invention
  • FIGS. 4 and 5 show concrete slabs reinforced respectively by mat structures according to FIGS. 1 and 2 and embodying the improvement according to the invention.
  • FIGS. 6a to 6e illustrate in a schematic manner various ways that the prior art structure of FIG. 6a can be modified with the strips as shown in FIGS. 4 and 5.
  • FIGS. 7a to 7d are views similar to FIGS. 6a to 6e, FIG. 7a being the prior art structure.
  • FIG. 8 is a view similar to FIG. 4, but showing a modified form of reinforcement which includes strips that cross each other.
  • FIG. 9 is a cross-sectional view of a modified form of reinforcing structure in which the end portions of the straps turn upwardly.
  • FIG. 1 presented for the sake of illustration of the invention, there is shown a section of a well-known composite reinforcing mat structure comprising a plurality of standard of unit mats 1 each consisting of longitudinal steel bars or rods 3 intersected by transverse bars 2 secured to the former at the intersection points, preferably by spot welding.
  • the longitudinal bars 3 in the example shown, are of constant diameter throughout the width of the mats and mutually spaced by constant distances a.
  • each two adjoining mats l overlap each other within a zone covering a single mesh, whereby the longitudinal bars 3 appear in double number within the overlap zones, to result thereby in an excess metal cross-section within said zones and in turn in nonuniform metal cross-section per unit width distribution across the width of the composite mat structure.
  • the marginal or overlap zones of the unit mats 4 are fitted with longitudinal bars 5 whose cross-section is equal to one-half the cross-section of the remaining bars 6 in the intermediate zones of the mats, to achieve thereby a uniform metal cross-section distribution across the entire mat structure, that is, including the marginal or overlap zones.
  • FIG. 3 shows a few possible constructions of the additional mat strips according to the invention superimposed upon an infrastructure of unit mats according to FIGS. 1 and 2 or any equivalent multiple mat assembly.
  • the mat strip 7 consists of two longitudinal bars 8 spaced by a distance b which may be equal to the spacing distance a, FIGS. 4 and 5.
  • the longitudinal bars 8 are connected by way of transverse bars 9 which may be of any number to serve as securing means of the rods 8.
  • the connections may be by means of welding, clamping, using metallic or synthetic clamps, by binding, or cementing preferably with the use of a synthetic glue or bonding material.
  • connections may be shear resistant, to cause the transverse rods to contribute to the anchoring effect to the concrete, or the connections may be of a non-shear resistant nature where the transverse rods 8, which may be of limited number, merely serve to secure the position of the longitudinal rods 8.
  • one or both of the longitudinal rods 8 of the mat strips may be in the form of twin rods and, finally, three, four or five longitudinal rods 8 may be distributed over the same width b of at least 200 mm, as shown by FIGS. 3d 3f, respectively.
  • FIGS. 4 and 5 there is illustrated the application of the invention to the reinforcement of a concrete slab 10, such as a floor, ceiling, etc.
  • the unit mats l of an infrastructure, according to FIG. 1 are combined with a single mat strip 7 disposed centrally between two successive overlap zones. If, in an arrangement of this type, the metal cross-section of the strip 7 corresponds to the excess metal or accumulation in the overlap zones, the successive accumuiations in the composite structure will result in a mean metal cross'section being uniformly distributed over the entire width of the structure and added to the basic cross-section of the infrastructure formed by the mats l, to result in a total reinforcement for the slab 10 in compliance with the particular requirements of the application at hand.
  • the mat strips 7 provided in addition to the mats 4 are advantageously spaced from the median lines of the overlap zones by distances equal to one-half of the constant mutual spacing distance between the mats, whereby to result in a uniform distribution of the metal accumulations added to the metal distribution of the infrastructure of the mats 4, across the entire width of the composite mat structure.
  • FIGS. 6a to 6e and 7a to 7d schematically illustrate arrangements of the type according to FIGS. 4 and 5, respectively, with means to control the metal crosssection distribution by the provision of varying numbers of mat strips between any two overlap zones of the basic or infrastructure, to enable the realization of a desired metal cross-section within a given practical operating range by means of a minimum number of unit mats and mat strips, respectively.
  • FIG. 6a shows an infrastructure composed of unit mats 11 similar to "FIG. I, the distance between the median lines of the overlap zones of the mats being denoted by S. If a single mat strip 12 is added to the infrastructure, the same is advantageously disposed midway of each mat 11, FIGS, 6b, that is, the metal accumularion are spaced by distances of 8/2. In FIGS. 6c6e, two, three and four strips 12, respectively, are disposed in equi-spaced relation within the distance S, resulting in metal accumulations throughout the width of the composite mat spaced by distances respectively of 8/3, 8/4 and /5.
  • FIGS. 7a to 7d show an arrangement similar to FIGS. 6a to 62 except for the overlap zones of the infrastructure, FIG, 7a having the same metal crosssection as the remaining zones by the provision of the longitudinal bars 13 of half the cross-section as shown in FIG. 2 and indicated by the thin marginal overlap portions of the bars 13 in the drawing.
  • FIG. 7a shows an arrangement similar to FIGS. 6a to 62 except for the overlap zones of the infrastructure, FIG, 7a having the same metal crosssection as the remaining zones by the provision of the longitudinal bars 13 of half the cross-section as shown in FIG. 2 and indicated by the thin marginal overlap portions of the bars 13 in the drawing.
  • the strips are spaced from each other by equal distances 8/2, 8/3 and 5/4, on the one hand, while the marginal strips are spaced from the median lines of the adjacent overlap zones by distances of 8/4, 8/6, and 5/8, respectively, on the other hand, as indicated in the drawing, in an effort to obtain a desired total and uniform metal cross-section distribution across the entire width of the composite structure.
  • FIG. 8 is similar to FIG. 4, but shows the cross-strip 7 in addition to the strip 7.
  • FIG. 9 is a cross-sectional view of an end portion of a structure taken at right angles to the views of FIGS. 4 and 5 so as to show the bending of the strip 7" towards the upper face of the structure.
  • a composite reinforcing steel mat structure for use in planar concrete construction units comprising a plurality of unit mats each composed of a pair ofintersecting sets of equi-spaced longitudinal and transverse bars connected at their intersection points, said mats arranged in juxtaposed relation with adjoining marginal longitudinal zones thereof overlapping each other over a distance of at least one mesh of the mats, to provide a reinforcing infrastructure of desired dimension and predetermined metal cross-section per unit width distribution across the width thereof, in combination with a multiplicity of relatively narrow reinforcing mat strip of approximately the width of the overlap in the infrastructure each composed of at least two longitudinal bars intersected by transverse bars connected thereto and overlying said infrastructure, said mat strips being spaced from each other and.the median lines of the overlap zone of said infrastructure, to cause the resultant metal cross-section accumulations by said strips in conjunction with the metal cross-section distribution of said infrastructure to produce a composite reinforcing structure with a predetermined total and substantially uniformly distributed metal reinforcement throughout the width of the composite mat structure.

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  • Engineering & Computer Science (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Reinforcement Elements For Buildings (AREA)
  • Working Measures On Existing Buildindgs (AREA)
  • Panels For Use In Building Construction (AREA)
  • Wire Processing (AREA)
US881821A 1968-12-05 1969-12-03 Reinforcing mat structure for planar concrete construction units Expired - Lifetime US3914915A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE1812865A DE1812865C3 (de) 1968-12-05 1968-12-05 Bewehrung fur flächige Betonbauteile

Publications (1)

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US3914915A true US3914915A (en) 1975-10-28

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US881821A Expired - Lifetime US3914915A (en) 1968-12-05 1969-12-03 Reinforcing mat structure for planar concrete construction units

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US (1) US3914915A (en, 2012)
JP (1) JPS5016568B1 (en, 2012)
AT (1) AT297283B (en, 2012)
BE (1) BE742647A (en, 2012)
BG (1) BG19199A3 (en, 2012)
BR (1) BR6914722D0 (en, 2012)
CH (1) CH511994A (en, 2012)
CS (1) CS156465B2 (en, 2012)
DE (1) DE1812865C3 (en, 2012)
ES (1) ES176942Y (en, 2012)
FR (1) FR2025406B1 (en, 2012)
GB (1) GB1255720A (en, 2012)
IE (1) IE33899B1 (en, 2012)
IL (1) IL33424A0 (en, 2012)
LU (1) LU59936A1 (en, 2012)
NL (1) NL6918095A (en, 2012)
NO (1) NO127117B (en, 2012)
PL (1) PL80693B1 (en, 2012)
SE (1) SE364336B (en, 2012)
YU (1) YU31886B (en, 2012)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057967A (en) * 1976-05-14 1977-11-15 Suntech, Inc. Reinforced ice matrix
US4519177A (en) * 1981-12-14 1985-05-28 Alphacrete Construction Linings (Uk) Limited Method for reinforcing tubular ducts
US4539787A (en) * 1981-11-20 1985-09-10 Avi Alpenlandische Veredelungs-Industrie Gesellschaft M.B.H. Reinforcement mat for reinforced concrete
US20110131905A1 (en) * 2009-12-07 2011-06-09 Paul Aumuller Cementitious deck or roof panels and modular building construction
US20190032336A1 (en) * 2016-07-15 2019-01-31 Richard P. Martter Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures
RU2686872C1 (ru) * 2018-04-25 2019-05-06 Василий Никитович Мазур Ледовая автодорожная переправа
US11220822B2 (en) 2016-07-15 2022-01-11 Conbar Systems Llc Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814943A (en) * 1955-10-12 1957-12-03 Bowie G Simmons Reinforcing trussed girder
US3302360A (en) * 1963-01-09 1967-02-07 Bjerking Sven-Erik Method of reinforcing concrete floors and the like, and a reinforcing element therefor

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB192198A (en) * 1921-11-07 1923-02-01 Arnhold Brothers And Company L Improvements in reinforcements for reinforced concrete
DE975059C (de) * 1954-02-14 1961-07-27 Baustahlgewebe Gmbh Bewehrungsanordnung fuer flaechenartige Stahlbetonbauteile
FR1215087A (fr) * 1958-11-05 1960-04-13 Procédé d'établissement d'armatures pour dalles en béton armé
FR1437626A (fr) * 1965-03-25 1966-05-06 Elément de renforcement à ancrage pour armature de béton armé

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814943A (en) * 1955-10-12 1957-12-03 Bowie G Simmons Reinforcing trussed girder
US3302360A (en) * 1963-01-09 1967-02-07 Bjerking Sven-Erik Method of reinforcing concrete floors and the like, and a reinforcing element therefor

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4057967A (en) * 1976-05-14 1977-11-15 Suntech, Inc. Reinforced ice matrix
US4539787A (en) * 1981-11-20 1985-09-10 Avi Alpenlandische Veredelungs-Industrie Gesellschaft M.B.H. Reinforcement mat for reinforced concrete
US4519177A (en) * 1981-12-14 1985-05-28 Alphacrete Construction Linings (Uk) Limited Method for reinforcing tubular ducts
US20110131905A1 (en) * 2009-12-07 2011-06-09 Paul Aumuller Cementitious deck or roof panels and modular building construction
US20190032336A1 (en) * 2016-07-15 2019-01-31 Richard P. Martter Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures
US10633860B2 (en) * 2016-07-15 2020-04-28 Conbar Systems Llc Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures
US11220822B2 (en) 2016-07-15 2022-01-11 Conbar Systems Llc Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures
US11788289B2 (en) 2016-07-15 2023-10-17 Conbar Systems Llc Reinforcing assemblies having downwardly-extending working members on structurally reinforcing bars for concrete slabs or other structures
RU2686872C1 (ru) * 2018-04-25 2019-05-06 Василий Никитович Мазур Ледовая автодорожная переправа

Also Published As

Publication number Publication date
JPS5016568B1 (en, 2012) 1975-06-13
BG19199A3 (bg) 1975-04-30
IL33424A0 (en) 1970-01-29
IE33899B1 (en) 1974-12-11
GB1255720A (en) 1971-12-01
BR6914722D0 (pt) 1973-05-08
BE742647A (en, 2012) 1970-05-14
NO127117B (en, 2012) 1973-05-07
CH511994A (de) 1971-08-31
FR2025406A1 (en, 2012) 1970-09-11
LU59936A1 (en, 2012) 1970-02-03
DE1812865A1 (de) 1970-06-11
YU299469A (en) 1973-06-30
PL80693B1 (en) 1975-08-30
DE1812865C3 (de) 1975-12-04
ES176942U (es) 1972-09-01
NL6918095A (en, 2012) 1970-06-09
YU31886B (en) 1973-12-31
ES176942Y (es) 1973-04-01
IE33899L (en) 1970-06-05
CS156465B2 (en, 2012) 1974-07-24
SE364336B (en, 2012) 1974-02-18
FR2025406B1 (en, 2012) 1976-03-19
AT297283B (de) 1972-03-27

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