Point-supported element or flat concrete ceiling

摘要

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).

主权项

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.