Point-supported element or flat concrete ceiling

• US 9,469,993 B2
• Filed: 06/18/2013
• Issued: 10/18/2016
• 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
• Primary Examiner(s): Fox, Charles A
• Assistant Examiner(s): SADLON, JOSEPH
• Application Number:
  US14/420,891
• Publication Number:
  US 20150204074A1
• Time in Patent Office: 1,218 Days
• Field of Search: 526/491, 526/90
• 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, comprising a transverse force and punching shear reinforcement having incorporated at least one lattice beam running in the longitudinal direction at least approximately to a vertical axis of a support point, supporting the element or flat concrete ceiling, the lattice beam comprising two spaced-apart lower chords and at least one continuous upper chord, 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 at securing points, wherein the diagonal struts of each serpentine diagonal strut section in the lattice beam are inclined in different directions upwards and towards the support, and wherein at least in the end region of the at least one lattice beam at the support one diagonal strut closest to the support is inclined at a steeper angle than 90°

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

flatter than the steeper angle when the lattice beam is installed, concreted and is supporting a load, such that, of upper and lower concrete anchoring zones respectively formed in a region of the securing points at least of the diagonal strut that is closest to the support and is inclined at the steeper angle smaller than 90°

, the upper concrete anchoring zone being defined by the upper bent portion and the upper chords in the securing point of the diagonal strut that is closest to the support lies closer to the support vertical axis than the lower concrete anchoring zone of the same diagonal strut, the lower concrete anchoring zone being defined by the lower bent portion of the diagonal strut that is closest to the support and a respective lower chord, and wherein the support has a rectangular or square or polygonal cross section, the upper concrete anchoring zone ending at least approximately with a vertical projection of a support side face or is offset beyond this in the direction towards the support vertical axis, and wherein 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.

2. 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.

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

4. 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°

.

5. Point-supported element or flat concrete ceiling according to claim 1, wherein a diameter of the chords is greater than a diameter of the serpentine diagonal strut section.

6. Point-supported element or flat concrete ceiling according to claim 1, wherein a reinforcement is provided in the support, the reinforcement being covered by a concrete cover defining the support side face, and 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 the support side face plus at least a portion of the size of the concrete cover covering the reinforcement in the support.

7. Point-supported element or flat concrete ceiling according to claim 1, wherein the flat concrete ceiling comprises prefabricated, adjacently arranged concrete slabs with a joint of predetermined width between adjacent concrete slabs, each concrete slab having a concrete top layer and, wherein an overhang of each upper concrete anchoring zone relative to each lower concrete anchoring zone of the same diagonal strut of the serpentine diagonal strut section and the diagonal strut closest to the support corresponds at least approximately to a distance of the edge of the concrete slab from a vertical projection of the support side face.

8. Point-supported element or flat concrete ceiling according to claim 7, wherein the overhang of the upper concrete anchoring zone corresponds at most to the distance of the edge of the concrete slab from the reinforcement in the support.

9. Point-supported element or flat concrete ceiling according to claim 7, wherein the overhang of the upper concrete anchoring zone corresponds at most to approximately half the half width of the joint between two adjacent concrete slabs.

10. Point-supported element or flat concrete ceiling according to claim 1, wherein in the lattice beam the upper bend portions are form loops which project upwardly beyond the upper chord or end at least approximately flush with a upper side of the upper chord.

11. A concrete ceiling point supported element comprising:

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

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

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 being secured at securing points to said upper chord, and the lower bent portions of one of said plurality of serpentine diagonal struts being secured at securing points to one of said plurality of parallel lower chords, and the lower bent portions of another one of said plurality of serpentine diagonal struts being secured at securing points to another one of said plurality of parallel lower chords, whereby the first and second alternating diagonal struts extend successively between and transverse to said upper chord and said plurality of parallel lower chords;

wherein one of the first alternating diagonal struts adjacent to the concrete anchoring zone end of the lattice beam transverses said upper chords and said plurality of lower parallel chords at a first angle of between eighty-five degrees and seventy-five degrees angling towards the concrete anchoring zone end; and

wherein the second alternating diagonal strut transverses said upper chord and said plurality of lower parallel chords at a second angle at least ten degrees less than the first angle and angles towards the concrete anchoring zone end.

12. A concrete ceiling point supported element for embedding in concrete having a lattice beam structure comprising:

an upper chord having a first diameter extending longitudinally and having a concrete anchoring zone end with an upper securing point;

a plurality of parallel lower chords having a diameter equal to the first diameter extending longitudinally and parallel to said upper chord, said plurality of parallel lower chords having a lower securing point, the upper securing point overhanging the lower securing point relative to a line extending perpendicularly through said upper chord and perpendicular to a plane formed by said plurality of parallel lower chords, whereby the upper securing point may be placed closer to a vertical support perpendicular to the lattice beam structure than the lower securing point;

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 extending beyond said upper chord and being secured to said upper chord in two different locations, and the lower bent portions of one of said plurality of serpentine diagonal struts being secured to one of said plurality of parallel lower chords, and the lower bent portions of another one of said plurality of serpentine diagonal struts being secured to another one of said plurality of parallel lower chords, whereby the first and second alternating diagonal struts extend successively between and transverse to said upper chord and said plurality of parallel lower chords, said plurality of serpentine diagonal strut sections having a second diameter, the second diameter being less than the first diameter of said upper chord and said plurality of parallel lower chords;

wherein one of the first alternating diagonal struts adjacent to the concrete anchoring zone end of the lattice beam transverses said upper chord and said plurality of lower parallel chords at a first angle of between eighty-five degrees and seventy-five degrees angled towards the concrete anchoring zone end; and

wherein the second alternating diagonal strut transverses said upper chord and said plurality of lower parallel chords at a second angle at least ten degrees less than the first angle and angles towards the concrete anchoring zone end,

whereby the upper securing point may be placed closer to a vertical support perpendicular to the lattice beam structure than the lower securing point assisting in preventing the propagation of cracks in a concrete ceiling.