DISEÑO DE LOSA ALIGERADA SEGUNDO NIVEL.pdf
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Transcript of DISEÑO DE LOSA ALIGERADA SEGUNDO NIVEL.pdf
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DISEO LOSA ALIGERADA SEGUNDO NIVEL
A B C D E F
4.48 m 5.590 m 5.860 m 5.725 m 5.35 m
4.025 m 5.290 m 5.560 m 5.425 m 4.900 m
METRADO DE CARGAS:
Peso Propio de Losa. 350 kg/m2 = 0.50 m
Peso Piso y Cielo Razo: 100 kg/m2 =
Peso de Cobertura Liviana: 25 kg/m2 =
475 kg/m2 = Wcm= 0.475 Tn/m2 0.30 m
Sobrecarga: 50 kg/m2 = Wcv= 0.050 Tn/m2
Carga de Diseo:
Wu = 1.4 Wcm + 1.7 Wcv
CARGAS MAYORADAS: Wu = 0.750 Tn/m2
Wu = 0.750 Tn/m2
A B C D E F
4.025 m 5.290 m 5.560 m 5.425 m 4.900 m
-
EMBOLVENTE :MOMENTOS MAXIMOS
-1.633 -1.892 -1.865 -2.064
-0.506 -0.750
A B C D E F
0.848 0.962 1.173 0.920 1.374
DISEO DE REFUERZO EN LA LOSA:
A)Para Momento Positivo: 1.374
bw=100cm f ' c = 210 Kg/cm2
f ' y = 4200 Kg/cm2
5 cm bw = 100.00 cm
rec. = 2.00 cm
Asumir = 1/215 cm d= 17.37 cm
Asumir que c = h f = 5.00 cm
25 cm a = c = 4.25 cm
Nota: Se calculara bw=100 cm Luego se dividira entre 2.5
2.38 cm2/m /2.5 Area de Acero en 1 metro de Aligerado:
As = 3.17 cm2/m
= 0.75 cm
A cada vigueta le corresponde = 0.95 cm2
Usar : 1 1/2 1.27 cm2 c = 0.88 cm OK!
0 3/8 0.00 cm2 Usar : 1 1/2 As = 1.27 cm2
1.27 cm2 Por lo Tanto: 0 3/8
.maxMu
)2
(9.0a
dfy
MuAs
bcf
fyAsa
'85.0
-
Calculo del Momento Resistente
= 2034.16 Kg-m/m
d = 17.37 cm2
RESUMEN :
TRAMO AB : As = 0.53 cm2 Usar : 1 1/2 1.27 cm2
0 3/8 0.00 cm2 1.27 cm2
TRAMO BC : As = 0.60 cm2 Usar : 1 1/2 1.27 cm2
0.00 cm2 1.27 cm2
TRAMO CD : As = 0.73 cm2 Usar : 1 1/2 1.27 cm2
0.00 cm2 1.27 cm2
TRAMO DE : As = 0.57 cm2 Usar : 1 1/2 1.27 cm2
0.00 cm2 1.27 cm2
TRAMO EF : As = 0.86 cm2 Usar : 1 1/2 1.27 cm2
0 3/8 0.00 cm2 1.27 cm2
B)Para Momento Negativo:
bw=100cm 2.064
5 cm f ' c = 210 Kg/cm2
f ' y = 4200 Kg/cm2
bw = 25.00 cm
15 cm rec. = 2.00 cm
Asumir = 1/2d= 17.37 cm
25 cm
Comprobando con las formulas de "a" y "As" tenemos:
)2
(*a
dfyAsM r
.maxMu
)2
(9.0a
dfy
MuAs
bcf
fyAsa
'85.0
-
Asumir valor de "a" A cada vigueta le corresponde = 1.39 cm2
a = 3.27 cm
As = 3.47 cm2 Usar : 2 3/8 1.43 cm2
a = 3.27 cm2 OK!
Calculo del Momento Resistente
= 2139.79 Kg-m/m d = 17.52375
RESUMEN :
APOYO "A" As = 0.34 cm2 Usar : 1 1/2 '' 1.27 cm2
0 0.00 cm2 1.27 cm2
APOYO "B" As = 1.09 cm2 Usar : 1 1/2 '' 1.27 cm2
0 3/8 '' 0.00 cm2 1.27 cm2
APOYO "C" As = 1.26 cm2 Usar : 1 1/2 '' 1.27 cm2
0 3/8 '' 0.00 cm2 1.27 cm2
APOYO "D" As = 1.24 cm2 Usar : 1 1/2 '' 1.27 cm2
0 3/8 '' 0.00 cm2 1.27 cm2
APOYO "E" As = 1.37 cm2 Usar : 1 1/2 '' 1.27 cm2
1 3/8 '' 0.71 cm2 1.98 cm2
APOYO "F" As = 0.50 cm2 Usar : 1 1/2 '' 1.27 cm2
0 0.00 cm2 1.27 cm2
4.025 m 5.290 m 5.560 m 5.425 m 4.90 m
1.01 m 1.32 m 1.32 m 1.39 m 1.39 m 1.36 m 1.36 m 1.23 m
1 0 3/8 0 3/8 0 3/8 1 3/8 1
1/2 1/2
1 1/2 1 1/2 1 1/2 1 1/2
1.01 m 1.31 m 1.72 m 1.72 m 1.81 m 1.81 m 1.76 m 1.76 m 1.59 m 1.23 m
0 3/8 0 0 0 0 0 0 0 3/8
1 1/2 1 1/2 1 1/2 1 1/2 1 1/2
0.56 m 0.56 m 0.74 m 0.78 m 0.78 m 0.76 m 0.76 m 0.69 m 0.69 m
As.Temperatura=1/4"@25cm
)2
(9.0a
dfy
MuAs
)2
(*a
dfyAsM r
-
VERIFICACION POR CORTANTE:
V A V 'B V 'C V 'D V 'E
Vud
d
V ''B V ''C V ''D V ''E V F
En losas Vs = 0
(Mr)A (Mr)B (Mr)C (Mr)D (Mr)E (Mr)F
1 1/2 1 1/2 1 1/2 1 1/2 1 1/2 1 1/2
0 0 0 3/8 0 3/8 0 3/8 1 3/8 0 0
A B C D E F
4.025 m 5.290 m 5.560 m 5.425 m 4.900 m
a) Calculo de los Momentos Resistentes: Mr
1 1/2
MrA : (As)A = 0 0 = 3.17 cm2 f'c = 210 Kg/cm2
fy = 4200 Kg/cm2
= 2.98 cm b = 25.00 cm
rec. = 2.00 cm
d = 17.37 cm
= 1900.35 Kg-m/m
dbcfVud
VcVud
VsVcVn
VnVud
.*'53.0*
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rA
-
MrB : (As)B = 1 1/2 = 3.17 cm2
0 3/8
= 2.98 cm
MrC : (As)C = 1 1/2 = 3.17 cm2
0 3/8
= 2.98 cm
MrD : (As)D = 1 1/2 = 3.17 cm2
0 3/8
= 2.98 cm
MrE : (As)E = 1 1/2 = 4.95 cm2
1 3/8
= 4.66 cm
= 1900.35 Kg-m/m
= 1900.35 Kg-m/m
= 2812.50 Kg-m/m
= 1900.35 Kg-m/m
)2
(.a
dfyAsM rA
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rB
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rC
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rD
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rE
-
MrF : (As)F = 1 1/2 = 3.17 cm2
0 0
= 2.98 cm
b) Calculo de los Esfuerzos Cortantes: Vi
V A = 1509.38 Kg 1509.375
V 'B = -1509.38 Kg 2202.51 Kg 1509.375
V ''B = 1983.75 Kg 1983.75
V 'C = -1983.75 Kg 1983.75
V ''C = 2085.00 Kg 2085
V 'D = -2085.00 Kg 2085
V ''D = 2202.51 Kg 2202.51269
V 'E = -1866.24 Kg 1866.23731
V ''E = 1651.35 Kg 1651.34756
V F = -2023.65 Kg 2023.65244
2072.28 Kg
Corte que toma el Concreto
Vc = 3334.27 Kg
= 1900.35 Kg-m/m
i
jiiuii
L
MMLWV
2
Vud
d
Vmax.=
Vud
WudVuVud
dbcfVC **'*53.0
bcf
fyAsa
'85.0
)2
(.a
dfyAsM rE
-
Vc = 2834.13 Kg OK!
bw =
Ensanche =
POR LO TANTO NO ES NECESARIO CALCULAR ENSANCHE DE VIGUETA
ViguetaEnsancharVcVudSi ..:
VuddbwcfV C **'*53.0.
dcf
Vudbw
*'53.0
LEnsanchedeLongitud :..
b=
L=
0.10
0.10
0.10