POINT-SUPPORTED ELEMENT OR FLAT CONCRETE CEILING

• US 20150204074A1
• Filed: 06/18/2013
• Published: 07/23/2015
• Est. Priority Date: 08/13/2012
• Status: Active Grant

• Current Assignee: Filigree Tragersteme GmbH & Co. KG.
• Original Assignee: Filigree Tragersteme GmbH & Co. KG.
• Inventors: Bauermeister, Ulrich, Furche, Johannes
• Granted Patent: US 9,469,993 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E04B 2103/02 of ceramics, concrete or other stone-like material
• CPC Class Codes: E04C 3/20 of concrete or other stone-like material, e.g. with reinforcements or tensioning members reinforcing elements E04C5/00
• CPC Class Codes: E04C 3/293 the materials being steel and concrete concrete with internal reinforcements or tensioning members E04C3/20
• CPC Class Codes: E04C 3/294 of concrete combined with a girder-like structure extending laterally outside the element light weight girders used as reinforcement E04C5/065; as part of a floor structure E04B5/23
• CPC Class Codes: E04C 5/06 of high bending resistance, i.e. of essentially three-dimensional extent, e.g. lattice girders anchorage devices specially adapted for balconies E04B1/0038; supporting devices for connector reinforcing rods for concrete walls E04G21/125
• CPC Class Codes: E04C 5/0645 Shear reinforcements, e.g. shearheads for floor slabs
• CPC Class Codes: E04C 5/065 Light-weight girders, e.g. with precast parts light-weight girders in general E04C3/08, E04C3/294
• CPC Class Codes: E04C 5/0653 with precast parts

Abstract

The invention relates to a point-supported element or flat concrete ceiling (BD) that comprises a transverse force and punching reinforcement (B) into which a lattice beam (1) that tapers on a support vertical axis (A) is integrated, wherein the lattice beam comprises lower chords (U) and a continuous upper chord (O) or anchoring elements (10) arranged with open spaces (Z) between one another and at least one serpentine diagonal strut section (D) with upper and lower bent portions (11, 12) between each two successive diagonal struts (S1, S2), said bent portions being secured in securing points (SO, SU). The diagonal struts (S1, S2) are angled in the same manner upwards and in the direction of the support (T). The diagonal strut (S1) nearest to the support is inclined at a steeper angle (α)<90° relative to the lower chords (U), and the preceding diagonal strut (S2) further from the support is inclined at an angle, which is flatter by at least 10°, of 45°≦(α2)<90° such that, of the concrete anchoring zones (VO, VU) formed by the diagonal strut (S1) nearest to the support, the upper concrete anchoring zone (VO) lies closer to the support vertical axis (A) than the lower concrete anchoring zone (VU).

Claims

1. Point-supported element or flat concrete ceiling, with a transverse force and punching shear reinforcement, in which there is incorporated at least one lattice beam which runs in the longitudinal direction at least approximately to a support vertical axis and which comprises two spaced-apart lower chords and either at least one continuous upper chord or anchoring elements arranged one behind the other with free intermediate spacings and at least one serpentine diagonal strut section with upper and lower bent portions between in each case two successive diagonal struts, said bent portions being secured to the lower and upper chords or to the lower chords and the anchoring elements at securing points, wherein the diagonal struts of each serpentine diagonal strut section in the lattice beam are inclined in the same direction upwards and towards a support, and that at least in the end region of the at least one lattice beam at the support, at least the diagonal strut closest to the support is inclined at a steeper angle (α

)<

90°

relative to the lower chords and the preceding diagonal strut remote from the support is inclined at an angle that is at least 10°

flatter, 45°

<

(α

2)<

90°

, such that, of upper and lower concrete anchoring zones formed in the region of the securing points at least of the diagonal strut that is closest to the support and is inclined at the steeper angle, the upper concrete anchoring zone lies closer to the support vertical axis than the lower concrete anchoring zone.

2. Point-supported element or flat concrete ceiling according to claim 1, wherein the support has a rectangular or square or polygonal or circular cross-section, and that the upper concrete anchoring zone ends at least approximately, preferably precisely, with a vertical projection of a support side face or is offset beyond this in the direction of the support vertical axis and that the lower concrete anchoring zone of the same diagonal strut closest to the support is set back from the vertical projection of the support side face.

3. Point-supported element or flat concrete ceiling according to claim 1, wherein the lower concrete anchoring zone is at a distance of at least approximately 2.0 cm from the vertical projection of the support side face.

4. Point-supported element or flat concrete ceiling according to claim 1, wherein an overhang of the upper concrete anchoring zone in the longitudinal direction of the lattice beam beyond the lower concrete anchoring zone of the diagonal strut closest to the support corresponds only at least approximately to the distance of the lower concrete anchoring zone from the vertical projection of the support side face.

5. Point-supported element or flat concrete ceiling according to claim 1, wherein the one diagonal strut or two diagonal struts integrated congruently in the lattice beam are regularly distributed along the length of the lattice beam and are inclined alternately at least approximately at the steeper and flatter angles.

6. Point-supported element or flat concrete ceiling according to claim 1, wherein the respective concrete anchoring zone is formed only of the bent portion or of the bent portion and the chord or the anchoring element, optionally including a cut-off chord piece or anchoring element piece which projects beyond the securing point in the direction of the support.

7. Point-supported element or flat concrete ceiling according to claim 1, wherein the bent portions between the diagonal struts are secured by weld spots at the securing points.

8. Point-supported element or flat concrete ceiling according to claim 1, wherein the steeper angle is approximately 70°

to 85°

, and in that the angle that is in each case at least 10°

flatter is approximately between 45° and

75°

.

9. Point-supported element or flat concrete ceiling according to claim 1, wherein the surface of the serpentine diagonal strut section and/or of the chords has a ribbed structure.

10. Point-supported element or flat concrete ceiling according to claim 1, wherein the diameter of the chords is greater than the diameter of the serpentine diagonal strut section, preferably the diameter of the chords is at least 10.0 mm.

11. Point-supported element or flat concrete ceiling according to claim 1, wherein the overhang of the upper concrete anchoring zone in the longitudinal direction of the lattice beam beyond the lower concrete anchoring zone corresponds at least approximately to the distance of the lower concrete anchoring zone from a vertical projection of a support side face plus at least a portion of the size of a concrete cover of a reinforcement in the support.

12. Point-supported element or flat concrete ceiling according to claim 1, wherein the ceiling comprises prefabricated concrete slabs with a concrete top layer and the lattice beam is concreted into the concrete slab.

13. Point-supported element or flat concrete ceiling according to claim 12, wherein the overhang of the upper concrete anchoring zone corresponds at least approximately to a distance of an edge of the concrete slab from a vertical projection of a support side face.

14. Point-supported element or flat concrete ceiling according to claim 12, wherein the overhang of the upper concrete anchoring zone corresponds at most to the distance of an edge of the concrete slab from a reinforcement close to the edge in the support.

15. Point-supported element or flat concrete ceiling according to claim 12, wherein the overhang of the upper concrete anchoring zone corresponds at most to approximately half the half-size of the width of a joint between two concrete slabs.

16. Point-supported element or flat concrete ceiling according to claim 1, wherein, in the lattice beam with at least one continuous upper chord, the upper bent portions either form loops which project beyond the upper chord or end at least approximately flush with the upper side of the upper chord.

17. Point-supported element or flat concrete ceiling according to claim 1, wherein the anchoring elements are premanufactured shaped parts or chord pieces and project beyond the upper bent portions at both ends in the longitudinal direction of the lattice beam.

18. A concrete ceiling point supported element comprising:

an upper cord extending longitudinally having a concrete anchoring zone end;

a plurality of parallel lower cords extending longitudinally and parallel to said upper cord;

a plurality of serpentine diagonal strut sections having first and second alternating diagonal struts, each of said plurality of serpentine diagonal strut sections having upper bent and lower bent portions, the upper bent portions of each of said plurality of serpentine diagonal strut sections attached to said upper cord, and the lower bent portions of one of said plurality of serpentine diagonal struts attached to one of said plurality of parallel lower cords and the lower bent portions of another one of said plurality of serpentine diagonal struts attached to another one of said plurality of parallel lower cords, whereby the first and second alternating diagonal struts extend between and transvers to said upper cord and said plurality of parallel lower cords;

wherein one of the first alternating diagonal struts is adjacent and spaced from the concrete anchoring zone end and transverses said upper cord and said plurality of lower cords at a first angle of between eighty-five degrees and seventy-five degrees angling towards the concrete anchoring zone; and

wherein the second alternating diagonal struts transvers said upper cord and said plurality of lower cords at a second angle at least ten degrees less than the first angle and angling towards the concrete anchoring zone,

whereby propagation of cracks in a concrete ceiling are prevented.