T-TYPE SHEAR CONNECTOR, FLOOR SYSTEM AND CONSTRUCTION METHOD THEREOF

Abstract

T-type shear connector, having: a first quadrilateral plate; and a second quadrilateral plate fixed perpendicularly and transversely, by way of one of its sides, on the middle part of the first quadrilateral plate. Formed floor system of metallic elements and concrete slab, including at least one T-type shear connector as described above, for connecting the metallic elements to the concrete slab; wherein the T-type shear connector is fixed from a cocked position. Method for constructing the floor system, including: fixing at least one T-type shear connector on the metal elements by way of a strong fastening element; and adding a concrete mixture on the metal elements and the T-type shear connector.

Claims

1. A floor system consisting of metallic elements and concrete slab, wherein it includes: at least, a T-type shear connector consisting of a first quadrilateral plate and a second quadrilateral plate fixed perpendicularly and transversely in the middle part of the first plate, to join the metallic elements to the concrete slab; where the T-type shear connector is fixed on the metallic elements by means of the free end of the second quadrilateral plate and any of the ends of the first quadrilateral plate, remaining in a tilted position and embedded in the concrete slab; y a strong clamping element connects the T-type shear connector to the metallic elements.

2. The floor system of claim 1, wherein the length of the second quadrilateral plate, of the T-type shear connector, is 32.33% less than the length of the first quadrilateral plate.

3. The floor system according to claim 1, wherein the quadrilateral plates have different widths from each other.

4. The flooring system according to claim 1, wherein the quadrilateral plates have different thicknesses from each other.

5. The flooring system of claim 1, wherein the quadrilateral plates are made of a flexural, compressive and shear resistant material.

6. The flooring system of claim 1, wherein the material with high flexural, compressive and shear strength is a metallic material.

7. The floor system according to claim 1, wherein the metallic material is A992 grade 50 steel.

8. The floor system according to claim 1, wherein both quadrilateral plates are: rectangular, quadrangular, trapezoidal, and/or a combination of shapes between said plates.

9. The floor system according to claim 1, wherein the T-type shear connector further comprises, a strong fastening element for tightly joining and fixing the quadrilateral plates to each other.

10. The flooring system of claim 1, wherein the means of strong attachment is selected from the following group: welds, glues or adhesives, assembly mechanisms, tongue and groove systems, and/or a combination thereof.

11. The floor system of claim 1, wherein the metal elements are: metal beams, metal slabs and/or compression mesh.

12. The flooring system according to claim 1, wherein the strong fastening element is selected from the following group: welding, glue or adhesive, an assembly mechanism, a tongue and groove system, and a combination thereof.

13. A method for constructing the floor system according to claim 1, wherein it comprises the following steps: to fix at least one T-type shear connector on the metallic elements by means of the free end of the second quadrilateral plate and any of the ends of the first quadrilateral plate, being in a tilted position; apply a strong fastening element, at the point where the edges of the ends of the quadrilateral plates make contact with the metallic elements; and add a concrete mix over the metal elements and the T-type shear connector, to form the concrete slab.

14. The method of claim 1, wherein the fastening element is welding, glue or adhesive, an assembly mechanism, a tongue and groove system and/or a combination thereof.

15. (canceled)

Description

[0008] FIG. 1 is a conventional perspective view of the T-type shear connector of the present invention.

[0009] FIG. 2 is another conventional perspective view of the T-type shear connector, according to the present invention.

[0010] FIG. 3 is a side view of the T-type shear connector in question.

[0011] FIG. 4 is a conventional perspective view of several T-type shear connectors, arranged in their position of use on steel elements that, together with the concrete slab, form a composite floor system.

[0012] FIG. 5 is the conventional perspective view of the previous figure, showing the addition of a reinforcing mesh.

[0013] FIG. 6 is the conventional perspective view of the previous figure, but now the inclusion of concrete is observed.

[0014] FIG. 7 is a longitudinal section of the composite floor system.

DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention relates to a T-type shear connector for joining beams and/or metal elements to a concrete slab; said T-type shear connector is an alternative to Nelson-type bolts and shear connectors based on Channel-type sections that are used to achieve composite behavior between steel elements and concrete elements to resist effects of different types of structural loading.

[0016] Thus a first object of the present invention is a T-type shear connector, which is composed of: [0017] i) a first quadrilateral plate (1); y [0018] ii) a second quadrilateral plate (2) fixed perpendicularly and transversely, by means of one of its sides, to the middle part of the first quadrilateral plate (1), thus forming a T-shaped piece.

[0019] One embodiment of the T-type shear connector of the present invention is where the length of the second quadrilateral plate (2) is 32.33% less than the length of the first quadrilateral plate (1); although there is also the embodiment where the length of the first plate (1) is twice the length of the second plate (2), such that the three ends of the T-type shear connector have the same length relative to each other.

[0020] A mode of the T-type shear connector, in question, is when the quadrilateral plates (1 and 2) have different widths from each other; although the mode is not ruled out when they have equal widths from each other said plates (1 and 2).

[0021] A further variant of the T-type shear connector of the present invention, is when the quadrilateral plates (1 and 2) have different widths or thicknesses from each other, but can also have equal widths or thicknesses from each other.

[0022] A further embodiment of such a T-type shear connector is where the plates (1 and 2) are manufactured from a material resistant to bending, compression and shear; for example, a metallic material, which may be steel, most preferably A992 grade 50 steel.

[0023] In yet another embodiment of the connector according to the present invention, it is when both quadrilateral plates (1 and 2) are: rectangular, quadrangular, trapezoidal, a combination of these shapes, or any other shape that allows for the configuration and operation of said connector.

[0024] A further variant of the connector according to the present invention is when it further comprises, in addition, a strong fixing element (not illustrated) for joining and strongly fixing the quadrilateral plates (1 and 2) to each other. This embodiment refers to when the connector is manufactured with two separate plates; as it can also be manufactured in one piece by means of a mold, lamination process, etc.

[0025] The means of strong fixation (not illustrated) can be selected from the following group: welds, glues or adhesives, assembly mechanisms, tongue and groove systems, a combination of these, to name a few examples.

[0026] A second object of the present invention is a floor system made up of metallic elements (3, 4 and 6) and concrete slab (5), where said floor system comprises, at least, a T-type shear connector, such as the one proposed and described in the present invention, for joining the metallic elements (3 and 4) with the concrete slab (5); where the T-type shear connector is fixed on the metallic elements (3 and 4) by means of the free end of the second quadrilateral plate (2) and any of the ends of the first quadrilateral plate (1), remaining in a tilted position and embedded in the concrete slab (5). The metallic elements are: metallic beams (4), metallic slabs (3) and/or reinforcement meshes (6), preferably.

[0027] The fastening of the T-type shear connector with the metallic elements (3 and 4) must be by means of any strong fastening element (7), such as: welding, glue or adhesive, an assembly mechanism, a tongue-and-groove system, a combination among them, etc.

[0028] The present invention has as a third object, a method for constructing the floor system, in accordance with the present invention, wherein said method comprises the following stages: [0029] i) to fix at least one T-type shear connector on the metallic elements (3 and 4) by means of the free end of the second quadrilateral plate (2) and any of the ends of the first quadrilateral plate (1), being in a tilted position; [0030] ii) to apply a strong fastening element (7), at the point where the edges of the ends of the quadrilateral plates (1 and 2) contact the metal elements (3 and 4); y [0031] iii) add a concrete mix over the metallic elements and the T-type shear connector to form the concrete slab (5).

[0032] The strong fastening element (7) that can be used to join the T-type shear connector with the metallic elements (3 and 4), can be welding, glue or adhesive, an assembly mechanism, a tongue and groove system, etc.

Advantages of the T-Type Shear Connector of the Present Invention Over Conventional Connectors

[0033] One of the advantages of the T-type connector over the Nelson and Channel type connectors is the mechanical behavior. The Nelson and Channel type connectors are controlled by the combination of bending and shear stresses; while the T-type connector withstands a combination of axial and bending stresses because it is used in a tilted position, where the steel is better able to resist the combination of stresses because of the tilted position.

[0034] Nelson Bolts are very efficient in forming a composite behavior between steel and concrete elements. However, they are expensive to manufacture because they are fabricated by means of a steel casting or cold punching process. Whereas, the T-type connectors of the present invention can be manufactured by cutting from rolled sections, which is a more efficient and economical process.

[0035] Another advantage of the T-Side connectors over the Nelson Bolt is that for the structural design of the Nelson Bolt there is a group factor that penalizes its strength when placed close together to increase the capacity of the connection. In contrast, the T-type connector only requires an increase in its dimensions, but it will remain a single connector. In addition, increasing the diameter of the Nelson Bolts to increase the capacity of the connection may cause the crushing of the concrete to become critical; but increasing the dimension of the T-type connectors maintains the same relationship, so it does not increase the probability of concrete crushing.

[0036] For the channel connector, its design is affected by a combination of relatively high bending and shear stresses, affecting the channel web. The web of the channels is the thinnest part, which makes it the weakest part of the section to resist this type of stress. For the T-type connector, its design is affected by tension in its second piece (2) or by a combination of relatively high axial and bending stresses and a relatively low shear stress at the ends, which make contact with the metallic elements (3 and 4), of the pieces (1 and 2).

EXAMPLES

[0037] The following examples are included for illustrative purposes only, as a demonstration of the conception and some preferred embodiments of the present invention; therefore, they are not to be considered as limiting the scope of said invention.

Example 1. T-Type Shear Connector, 5 cm Long

[0038] A T-type shear connector was fabricated using a first rectangular plate (1) of 103.0?50.0?10.3 mm; and a second rectangular plate (2) of 69.7?50.0?6.7 mm; both plates were made of A992 grade 50 steel with a yield strength of 3,515 Kg/cm.sup.2. The second rectangular plate (2) was welded perpendicularly and transversely through one of its ends in the middle part of the first rectangular plate (1), with a weld E7018 of a nominal resistance of 4,900 Kg/cm.sup.2, thus forming a T-shaped piece, see figures.

[0039] The T-shear connector obtained had the following structural characteristics: a weight of 0.60 Kg, whose technical effects were: a connecting capacity of 14,934 Kg, which was 27.3% higher with respect to the channel type shear connectors; although it is true that its weight increased by 11.2% with respect to the weight of the channel type shear connectors, but it still showed an increase in efficiency of 14.47%. This T-type shear connector had a tensile rupture capacity of the second plate (2), in its tilted position, of 15.081 kg (1.5 kg).

Example 2. Construction of a Floor System Using T-Type Shear Connectors

[0040] The floor system was built using steel beams (4), on which a ribbed steel plate (3) was placed, and in each of its channels was welded 1 T-type shear connector described in the previous example, which was positioned in a tilted way, that is, two of the ends of the T-type connector were fixed to the beam through the steel plate (3), see FIGS. 4, 5 and 7. In such a way that the end that makes contact with the plate (3) or beam (4) of the first plate (1) supports greater axial stresses, The other end of the first plate (1) supports minor axial, shear and bending forces, which are caused by the concrete slab (5). A reinforcing mesh (6) was placed over the steel slab (3) and the T-type shear connectors; and then a conventional concrete mix was added to form the concrete slab (5). In this way, the beams (4), reinforcing mesh (6) and steel (3) were connected to the concrete slab (5) by means of the T-type shear connectors.

[0041] This example illustrated a composite action consisting of the concrete slab (5) subjected to compression, the steel beam (4) subjected to tension and the T-type shear connectors joining them to generate a single element resisting bending stresses. The stresses of the T-type shear connector elements fabricated according to example 1, withstood the following stresses in their tilted position and immersed in the concrete slab (5), shown in Tables 1, 2 and 3.

TABLE-US-00001 TABLE 1 Stresses in the second plate (2). Type of stress Quantity Axial tension at support end 15,081.00 Kg Axial tension at both ends of first plate (1) 8,879.89 Kg Support shear 1,370.60 Kg Shear at lower end of first plate (1) 1,732.13 Kg Shear upper end of first plate (1) 2,765.89 Kg Support moment 0.00 Kgm Moment lower end of the first plate (1) 11.62 Kgm Moment upper end of the first plate (1) 52.27 Kgm

TABLE-US-00002 TABLE 2 Stresses in the lower end of the first plate (1). Type of stress Quantity Axial compression 6,903.84 Kg Shear 2,672.97 Kg Moment 105.99 Kg

TABLE-US-00003 TABLE 3 Stresses at the upper end of the first plate (1). Type of stress Quantity Axial compression 4,133.59 Kg Shear 6206.92 Kg Moment 158.26 Kg

BIBLIOGRAPHIC REFERENCES

[0042] Khorramian K, Maleki S, Shariati M, Ramli Sulong NH (2015) Behavior of Tilted Angle Connectors. PLoS ONE 11(2): e01448945.