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001028
4.6.2024

Posouzení na protlačení pro středový sloup v ploché desce podle Eurokódu 2 (EC2)

Popis

V tomto verifikačním příkladu posoudíme únosnost ve smyku při protlačení vnitřního sloupu ploché desky. The column has a circular secton with a 30cm diameter.

Materiál Concrete C30/37 Modul pružnosti E 33000 N/mm2
Návrhová hodnota pevnosti betonu v tlaku fcd 17.000 N/mm2
Reinforcing Steel B500S(A) Návrhová mez kluzu fyd 434.783 N/mm2
Geometrie Flat slab Tloušťka desky h 240 mm
Span of a panel in y-direction leff,y 7.000 m
Span of a panel in x-direction leff,x 5.000 m
Column Délka lColumn 4.000 m
Cross-section diameter d 300 mm
Zatížení Permanant loads Železobetonová deska p 36.680 kN/m2
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Concrete Design Ultimate Configurations

  • The used punching load is a single force from the column
  • The applied method for determining the factor β: Constant factors according to figure 6.21N

Výsledky

In the following, the RFEM 6 shear punching results are compared to the results of the reference.

Punching Shear Desgin Acc. to DIN EN 1992-1-1
Parametr Symbole Jednotka RFEM Analytické řešení Využití
Design Shear Force VEd kN 500.850 500.000 1.002
Mean effective depth d mm 210 210 1.000
Factor β β [-] 1.10 1.10 1.000
Length of basic control perimeter u1 m 3.581 3.581 1.000
Applied maximum shear stress νEd kN/m2 732.530 731.000 1.002
Parameter CRd,c CRd,c [-] 0.12 0.12 1.000
Factor k for calculation of design value for shear resistance k(6.47) [-] 1.980 1.976 1.002
Reinforcement ratio for longitudinal reinforcement ρl,1,-z(top) % 0.499 0.500 0.998
Characteristic cylinder compressive strength of concrete fck N/mm2 30 30 1.000
Normal concrete stresses in critical section σcp N/mm2 0 0 1.000
Basic shear resistance νRd,c,calc,1(2d) kN/m2 584.290 585.000 0.999
Minimum shear strength of plain concrete νmin kN/m2 532.450 532.000 1.001
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Punching shear reinforcement is necessary.

Punching Shear Reinforcement
Parametr Symbole Jednotka RFEM Analytické řešení Využití
Maximum shear resistance νRd,u1,max kN/m2 818.020 819.000 0.999
Basic shear resistance with required longitudinal reinforcement νRd,c,req,out kN/m2 486.910 487.500 0,999
Outermost control perimeter uout,ef m 5.388 5.372 1.003
Distance between loaded area and outermost control perimeter lw,out m 0.708 0.705 1.004
Designed number of perimeters n 3 3 1.000
Required punching reinforcement area of one perimeter Asw,stat,i cm2 3.350 3.600 0.931
Required punching reinforcement area of 1st perimeter Asw,req,1st cm2 8.360 9.100 0.919
Required punching reinforcement area of 2nd perimeter Asw,req,2nd cm2 4.680 5.100 0.918
Required punching reinforcement area of 3rd perimeter Asw,req,3rd cm2 3.350 3.600 0.931
Required punching reinforcement area of 3rd perimeter Asw,req,3rd cm2 3.350 3.600 0.931
Distance from loaded area to 1st perimeter of punching reinforcement lw,1st,req m 0.105 0.105 1.000
Distance from loaded area to 2nd perimeter of punching reinforcement lw,2nd,req m 0.249 0.262 0.950
Distance from loaded area to 3rd perimeter of punching reinforcement lw,3nd,req m 0.393 0.420 0.936
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Overall, the results from RFEM 6 show a high level of agreement with the reference data, with most ratios between 0.910 and 1.000.


Reference
  1. Goris, A. (Ed.), Hegger, J. (Ed.), & Mark, P. (Ed.). (2013). Stahlbetonbau aktuell 2014: Praxishandbuch (Bauwerk).