Prediksi kekuatan Balok beton bertulang

2009-11-04_232749

Menghitung momen tersedia :

Titik berat tulangan tarik,
CG_tul = c_v + d_tul + (D_tul/2)
= 30.00 + 8.00 + (13.00/2)
= 44.00 mm
Tingi effektif balok,

d = h – CG_tul
= 400.00 – 44.00
= 356.00 mm

Rasio tulangan

rho = A_st / (b * d)

= 398.20 / (200.00 * 356.00) = 0.56 %

rho_maks = 0.75 * rho_b = (382.5 * beta_1 * f_c) / ((600 + f_y) * f_y)

= (382.5 * 0.85 * 21.15) / ((600 + 400.00) * 400.00) = 1.72 %

Kontrol : rho < rho_maks 0.56 % < 1.72 % … Okey

Gaya tarik baja tul.,

T_s = A_st * f_y = 398.20 * 400.00 = 159278.75 N

Gaya tekan beton,

C_c = 0.85 * f_c * a_t * b

= 0.85 * 21.15 * a_t * 200.00 = 3595.50*a_t N

Persamaan kondisi kesetimbangan, T_s = C_c

Tinggi blok tekan beton,

a = 159278.75 / 3595.50 = 44.30 mm

Momen nominal,

M_n = T_s * (d – a/2)
= 159278.75 * (356.00 – 44.30/2)
= 53175252.00 N.mm = 53.18 kN.m

2009-11-04_232728

Perbandingan :

M & V dibuat incremental, Gaya N tidak ada

@ maksimum M = 45.8 kN.m, V = 45.8 kN, P = 0.0 kN

Vmaks < (1/6)*Sqrt(21.15)*200*356 = 54.57 kN

Gaya tarik baja atau tekan beton, R1 = 159/151 = ~5%

Lengan momen, R2 = 333.85 / 303.00 = ~10%

Momen nominal, R3 = 53.18/45.7 = ~16%

mphinovn

M dibuat incremental, Gaya V & N tidak ada

@ maksimum M = 71.6 kN.m, V = 0.0 kN, P = 0.0 kN

Gaya tarik baja atau tekan beton, R1 = 159/233 = ~32%

Lengan momen, R2 = 333.85 / 308.00 = ~8%

Momen nominal, R3 = 53.18/71.6 = ~26%

mphimvn

M, V & N dibuat incremental

@ maksimum M = 40.3 kN.m, V = 40.2 kN, P = 40.3 kN

Pmaks < 0.1*21.15*200*400 = 169.20 kN

Momen nominal, R3 = 53.18/40.39 = ~32%

mphinov

M & N dibuat incremental, Gaya V tidak ada

@ maksimum M = 61.7 kN.m, V = 0.0 kN, P = 61.7 kN

Pmaks < 169.20 kN

Momen nominal, R3 = 53.18/61.7 = ~14%

chart

Steel rebars and concrete properties

2009-11-04_234227

Concrete Materials

stress_strain_concrete_compression

Rebar materials

rebar

steelmat

… in draft

2 thoughts on “Prediksi kekuatan Balok beton bertulang

  1. untuk penjelasan diatas mas suyono pake software apaan??, ada gak literatur lengkap yg membahas asumsi untuk input nilai properti mekanis seperti diatas.
    tolong bantuannya mas, terima kasih..

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