Vigas - Flexão Simples 11

FLEXÃO SIMPLES

Neste exemplo, será dimensionada a armadura longitudinal e transversal de uma viga submetida a Flexão Simples utilizando como base a Norma ACI318-19, conforme dados abaixo:

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Concreto - C25 (4000 psi) / Aço – ADN420 (60 ksi)

bw: 8 in / h: 24 in

Mu:

TQS = 3301,05 kip.inSoftware B = 3395,75 kip.inSoftware C = 3303,71 kip.in


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Flexão:

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As,min (ACI 318-19 – 9.6.1.2)

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3,60 in2 ≥ 3,43 in2 → OK!

7f431cea53e7e7d80c729943288aa19d.png

øMn (3571,52 kip.in) ≥ Mu (3301,05 kip.in) → OK!!


Verificação do fator de redução (ACI318-19 – 21.2.2)

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0,0043 ≤ 0,005 → Não OK!!

Recalculando para armadura dupla:

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TQS:Software BSoftware C
As = 3,35 in²As = 4,15 in²As = 3,29 in²
A's = 0,23 in²A's = 0,65 in²A's = 0,27 in²

3,60 in² ≥ 3,35 in² → OK!

7f431cea53e7e7d80c729943288aa19d.png

øMn (3430,56 kip.in) ≥ Mu (3301,05 kip.in) → OK!

Cortante:


TQSSoftware BSoftware C
Vu = 71,86 kipsVu = 68,90 kipsVu = 71,73 kips
Vu,design = 52,70 kipsVu,design = 52,59 kipsVu,design = 52,04 kips

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Vs ≤ Vs,lim OK!

    Ø0,75 → øVn ≥ Vu → 52,70 ≥ 52,70 → OK!!

    Área de Aço:


    ccd86b2bda372870dd66e29bd88af607.png


    ec5e2b756a07c720342b191606d8fa18.png

    3839d14c2d8aa8169cf2d179395ffb2a.png

    59e62252b325d2a5f6a55e518cdbdac2.png


    Espaçamento:

    06d1e07ea784adbc04a385a9e9430ab3.png

    02857ec2c6a22e9db2eecd9edf817876.png

    a5990f4f9de2b71f619b44f71afd9e6b.png


    øVn (53,73 kips) ≥ Vu (52,70 kips)






    Vigas - Flexão Simples 10
    Vigas - Flexão Simples - Balanço 1