UNIVERSIDAD JO JOSE CA CARLOS MARIATEGUI FACUL ACULT TAD DE INGENIERI INGENIERIA A CIVIL CI VIL
INDICE .............................. ..................... ...................... ..................... ...................................... ............................ 2 1. Introducción....................
1.1. 1.1. Estruc Estructur tura a del Tronco ronco....................................................................4 ............................... ..................... ..................... ............................. .................. 5 1.2. 1.2. Famil amilia ias s Mader Maderab able les s.................... ................................ ...................... ..................... ............................. ...................6 6 1.3. 1.3. Prop Propie ieda dade des s fs fsic icas as.....................
1.!. 1.!. El merc mercad ado o mad mader erer ero o....................................................................8 1.". 1.". Norm Normas as de dise dise# #o..........................................................................9 2. MET$D$ MET$D$% % DE DI%E DI%E&$ &$ ' (N() (N()I%I I%I% % E%T*+ E%T*+CT+ CT+*() *().........................10 2.1. 2.1. M,to M,todo dos s de Dis Dise# e#o o......................................................................10 2.2. 2.2. Esfuer Esfuer-os -os ue resist resiste e la madera madera...............................................10 2.3. 2.3. P*$P P*$PIE IED( D(DE DE% % E)/%T E)/%TIC IC(% (%..................... ............................... ..................... ............................ .................12 12 ................................ ...................... ..................... ..................... ..................... ..................... ................ .....14 14 2.!. C0lculos..................... ............................... ..................... ..................... ..................................... ........................... 15 3. DI%E& I%E&$ $ DE I I(% (%.....................
3.1. 3.1. P*$PIE P*$PIED(D D(DE% E% DE DE )(% )(% %ECCI$ %ECCI$NE% NE%..................... ................................ ..................... .............15 ...15 3.2. 3.2. DEF) DEF)E EI$ I$NE NE% % (DMI% (DMI%I4 I4)E% )E%.........................................................17 ............................... ..................... ...................... ............18 18 3.3. 3.3. *E5+ *E5+I% I%IT IT$% $% DE *E%I *E%I%T %TEN ENCI CI( (.................... ............................... ..................... ...................................... ........................... 22 3.!. 3.!. E%C+ E%C+(D (D*6 *6( ( 7PTIM 7PTIM( (.....................
3.". 3.". I( I(% % C$MP C$MP+E +E%T %T(% (%....................................................................24 :............................... ..................... ..................... ..................... ........................................... ................................. 29 E8emplo 1:.................... :............................... ..................... ..................... ..................... ........................................... ................................. 35 E8emplo 2:.................... .............................. ..................... ............................39 .................39 E8emplo 39 DINTE) DE ENT(N(.................... :............................... ..................... ..................... ..................... ........................................... ................................. 43 E8emplo !:....................
1. Introd Int roducci ucción ón
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL τ =
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y R : Rai! "r!#$i! $ tr!%&!
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x
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4 3
= 2 + '2
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL I=
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2
∴ b =
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL R$$"+(!!/#, - $/ $!*/ B1:
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
= µ ⋅ s ⋅ 8 . ⇔ µ ⋅
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL H=
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
adσ
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•
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DISEÑO EN ACERO MADERA
3
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
=
C ! ⋅ $2 /
300 ⋅ *52 = /
= 15/43/ B ⋅ m
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=
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= + P8
31
32
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
=
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= 10%2 5
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DISEÑO EN ACERO MADERA
=
⋅ ma b ⋅ h 2
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
=
+
⋅ 1%42/1
= 111 54
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τ=
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2%5
=
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= 23
L! Q$! $ +%,#$ (! !%! '$%:
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cm
33
3!
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
=
5 ⋅ ⋅ l4 3/4 ⋅ ⋅ I
5 ⋅ 33 ⋅ 50 4
=
3/4 ⋅ D5000 ⋅
15 ⋅ 253
= 413
cm
12
∴ CAMBIAR ESCUADRIA! C,", $')$ ;!(,% $' "!=,% !( !#"*'*($& $/),/$' ?!((!& L,' )%$' ?$/"$/,' BQ$-*/& ,%)$ = #$?,%"!*/ /, ',/ !*'(!#,'& '$ +%$'$/)!/ '*"()/$!"$/)$. E/ $/$%!( $/ (!' "!#$%!' (! #$?,%"!*/ $' $( ?$/"$/, "' +$(*%,',& "!' $ (! Q$-*/& "!' $ $( ,%)$. ,% $', '$ $-*$ $/ (!' "!#$%!' / ,$@*$/)$ #$ '$%*#!# +!%! (! #$?,%"!*/ $/)%$ 1.5 ! 2. C,", (! $'!#%! !'"*#! $' */'@*$/)$: AFINAMIENTO
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C!
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C T 342 K" DEF$*M(CI$N 9 L! Q$! $ +%,#$ (! !%! '$%:
f =
5 ⋅ q ⋅ l 4 384 ⋅ E ⋅ I
=
5 ⋅ 342 ⋅ *50 4 3/4 ⋅ D5000 ⋅
15 ⋅ 353
= 15*
cm
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C,", $')$ ;!(,% $' "$/,% !( !#"*'*($& $/),/$' "+($. DISEÑO EN ACERO MADERA
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL E( ,$@*$/)$ #$ '$%*#!# ! (! #$?,%"!*/ '$%:
C.Seg
=
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=
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DISEÑO EN ACERO MADERA
3"
3>
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
E8emplo 2: S$ #*'+,/$ #$ "!#$%! #$( %+, A +!%! ,/')%*% /! ;*! #$ +$/)$& +,% $( +$/)$ )%!/'*)! $( )%$/ $ '$ ,'$%;! $/ (! @%!. D$)$%"*/$ (! $'!#%! #$ (! ;*!. E( $'$"! $' $( '**$/)$:
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b = 3
adσ
A,%! '$ !((! $( ","$/), +%,#*#, +,% (! !%! ;*;!& +!%! $'), '$ *! (! !%! $/ (! +,'**/ "' #$'?!;,%!($ B!/(*'*' #$ (/$! #$ */Q$/*!:
-*2 t
-*2 t
A
0
2*2+#
= P⋅a D$ (,' ?,%"(!%*,' #$ (,' !/$-,' #$( !+*)(, 3:
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= 200 ⋅ 225 = 450 B ⋅ m
3@
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL $%, !#$"' '$ #$$ !$% */*#*% $( ,$@*$/)$ #$ '$%*#!# ! Q$-*/ B'$ ),"!% $( ;!(,% #$ 2.E/),/$' (! !'$ '$%:
b =
3
2 ⋅ 45000 210
= D50cm
2
h = 1%3 ⋅ D50 = 1*435cm $%, ,", +,% (, $/$%!( (! ,"$%*!(*!*/ #$ (! "!#$%! '$ %$!(*! $/ +(!#!'& '$ ;$ +,% ,/;$/*$/)$ %$#,/#$!% (!' #*"$/'*,/$' #$ (! '$*/& = !#$"' !"$/)!%(! / +,, #$*#, ! $ /, '$ )," $/ $/)! $( +$', +%,+*,:
12.5 " ESCUADR1A:
25 " E( +$', +%,+*, '$%: + 750 K" 3 . 0.125 " . 0.25 " 23.44 K"
+25 K"
E%T/TIC(9 D$$ +,'**,/!%'$ $( )%$/ #$ )!( "!/$%! $ $'! +,'**/ $/$%$ (,' $'?$%,' "-*",' BF($-*/& ,%)!/)$ = #$?,%"!*/.S$ ,(,!/ (!' #,' !%!' '*")%*!' %$'+$), $( $/)%, #$ (! ;*! B!/(*'*' #$ (/$! #$ */Q$/*!. F)EI7N 9 L! '$*/ %)*! +!%! $( ","$/), "-*", $' $( $/)%, #$( )%!", +,% )!/), #$$ '*)!%'$ $( )%$/ #$ "!/$%! ,"+!%)*#! %$'+$), !( $/)%,.
-*2 t
-*2 t
A
0
x 2+ 3
∑
= 0 ⇒ ( 225 + 3%5) ⋅ 200 − ⋅ + 150 ⋅ 3 = 0
= 2%5B ⇒ = = 2%5B
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2+ 3
3A
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
555.46 K Z "
= 2%5 ⋅ - 25 ⋅ 0 < < 225
2
0 K Z"
2
562.50 K Z "
= 2%5 ⋅ - 25 ⋅ 225 < < 3
+
=
+
=
2
2
− 200 ⋅ ( x − 225 )
555.46 K Z "
⋅ ma b ⋅ h
2
* ⋅ 5*250 125 ⋅ 252
= 432
< adσ ⇒ IE
B&cm 2
C$*TE9 L! '$*/ %)*! +!%! $( ,%)!/)$ "-*", $' $/ $( $-)%$", #$( )%!", B!(*$% $-)%$",& +,% )!/), $( )%$/ #$ !%!' #$$ '*)!%'$:
-*2 t
-*2 t
A
0
42+ 3
∑
= 0 ⇒ 15 ⋅ 200 + 150 ⋅ 3 − ⋅ = 0
= 125B * ⋅ - * ⋅ 200 - 45 ⋅ 200 - 3 ⋅ 150 = 0
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12+ 3
3B
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
#
= 425B ⇒ A
= 3⋅
ma
3
τ =
2 b ⋅ h
⋅
425
= 204
2 125 ⋅ 25
[
B&cm 2
< adτ ⇒ IE
DEF$*M(CI7N9 L! Q$! $ +%,#$ (! !%! '$%:
- *2 t
-*2 t
A
1
=
5 ⋅ ⋅ $4 3/4 ⋅ ⋅ I
5 ⋅ 025 ⋅ ( *00)
=
3/4 ⋅ D5000 ⋅
-*2
0
A
0
t
A
4
125 ⋅ 25 3
= 02% cm
12
2
!
=
P⋅a 24 ⋅ ⋅ I
(3 ⋅ $2
200 ⋅ 225
− 4⋅a2) =
24 ⋅ D5000 ⋅
125 ⋅ 25
3
⋅ (3 ⋅ *00 2 − 4 ⋅ 225 2 ) = 10* cm
12
= 1 + 2 = 02% + 10* = 133 cm
ad =
$(cm) 250
=
*00 250
= 24 cm ⇒ ! < ad ⇒ IE
C$EFICIENTE% DE %E+*ID(D =$)+*(G9 F($-*/:
C,e@
=
adσ
σ
=
210 432
= 4/*
C,%)!/)$:
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-*2 t
0
!
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
C,e@τ
=
adτ
τ
=
15 204
= %35
D$?,%"!*/
C,e@ f =
ad f
f
=
240 133
= 1/1
L! $'!#%! $/,/)%!#! '$ $/$/)%! #$/)%, (, !$+)!($ #$/)%, #$( "!%, #$ (! '$%*#!# B+$%, $' antieconómico.
E8emplo 39 DINTE) DE ENT(N( Madera rupo9 4
'*./ )1%+*/+ Mam1/.!%+*a 7% (a7+*66/ 8amb/!% 7% "a+ga 2,-0 m
3*!%6 7% Ma7%+a
()z (*b+% = 2m 0 cm 2,0 m
E!+%ga / 3%.ca./ 4m**m/ 0 cm5
A #*?$%$/*! #$ (,' !/)$%*,%$' $$%**,' !,%! (! !%! /, $')! #!#!& #$$ $( */$/*$%, +%,%!% $')*"!% (! !%! ,/ (! "!=,% +%$*'*/ +,'*($. D$ /!#! '$%;*% !(*$% !@/!"*$/), !%*)")*, , !($%!*, '* (! !%! /, ! '*#, !#$!#!"$/)$ $')*"!#!. E-*')$/ #,' +,'**(*#!#$' +!%! $')*"!% (! !%!:
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!1
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
2,0m 1m
α
α
9 2,0m
S$ ,/'*#$%!% $( $?$), !%, ,/:
50° < α < 5°
C((, #$ :
tan( 0F ) =
h 230 & 2
C,/ / α 60\:
h
= 1DDm ≅ 20m
C((, #$( %$!:
1 ⋅115 ⋅ 2 2
= 2
= 23m 2 C((, #$ -:
2 115
=
1
= 05%5m !%! $( (!#%*((,:
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!2
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
G $ad=;llos ≅ 130
Peso 8 & cada $ad=;llo = 25B@
Peso total de $ad=;llo = 130 ⋅ 25 ⋅ 23 = %4%5B@ ≅ %4/B@
!%! $( ",%)$%,:
ol
ol
Peso es8ec;;co del mo=te=o = 2200
B@ m3
Peso total del mo=te=o = 01/ ⋅ 2200 = 3DB@
P!
= Plad + Pmo=t = %4/ + 3D* = 1144B@
Peso total9 A,%!& #*')%*=$/#, $( $', ),)!( $/ (! (,/*)#: !
=
P! $
=
1144 230
= 4D%4
B m
A,%!& (, $ ?!()! $' !'"*% (! $'!#%! #$( #*/)$(: E/),/$':
b = 3
2⋅ adσ
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!3
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL A,%! '$ !((! $( ","$/), +%,#*#, +,% (! ',%$!%!:
=
C ! ⋅ $2 /
4D%40 ⋅ 23 2
=
/
= 32/D1 B ⋅ m
$%, !#$"' '$ #$$ !$% */*#*% $( ,$@*$/)$ #$ '$%*#!# ! Q$-*/ B'$ ),"!% $( ;!(,% #$ 2.E/),/$' (! !'$ '$%:
b =
3
2 ⋅ 32/D1 150
= D5%cm
2
h
= 1%3 ⋅ D5% = 155cm
$%, ,", +,% (, $/$%!( (! ,"$%*!(*!*/ #$ (! "!#$%! '$ %$!(*! $/ +(!#!'& '$ ;$ +,% ,/;$/*$/)$ %$#,/#$!% (!' #*"$/'*,/$' #$ (! '$*/& = !#$"' !"$/)!%(! / +,, #$*#, ! $ /, '$ )," $/ $/)! $( +$', +%,+*,:
10 "
ESCUADR1A:
$', +%,+*, #$ (! "!#$%!:
Pmad
= 010 ⋅ 01%5 ⋅ %00 = 1225
!otal
B m
= 4D%4 + 1225 = 50D5
B@ m
Cara total9 F)EC=(9 L! Q$! $ +%,#$ (! !%! '$%:
f =
5 ⋅ q ⋅ L4 384 ⋅ E ⋅ I
=
5 ⋅ 50D% ⋅ 230 4 3/4 ⋅ %5000 ⋅
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10 ⋅ 1%53 12
= 052
cm
!!
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL C,", $')$ ;!(,% $' "$/,% !( !#"*'*($& $/),/$' "+($. E( ,$@*$/)$ #$ '$%*#!# ! (! #$?,%"!*/ '$%:
C,e@ =
ad
=
0D2 052
= 1%%
E')$ ;!(,% #$ ,$@*$/)$ #$ '$%*#!# ! (! #$?,%"!*/ $/)%! $/ $( %!/, %$,"$/#!#, #$ 1.5 ! 2& +,% (, )!/), (! $'!#%! !'"*#! "+($ B'$ +$#$ !@/!% !/ "'& $/ '! #$ ba8ar los costos. DET())E C$N%T*+CTI$9 ,% %!,/$' ,/')%)*;!' : !'$ #$ #*/)$( 7.5" ,% %!,/$' )$%*!'
: !'$ #$ #*/)$( 5"
%,?/#*#!# #$ (!;,
: +%,?. 18 "
1-,5
"($VO
-,5
E8emplo !: D$)$%"*/!% (! $'!#%! #$ "!#$%! +!%! (! ;*! A& = #$)$%"*/!% '* ,%%$'+,/#$ %$?,%!% (! $'!#%! ,/ +$%@($' #$ !$%,. E/ $( '*)*, (,' )%,/,' ',/ ;$/$' = +,% ,/'**$/)$ #$ +,, #*"$)%,.
, =1 t/#
A
0 2*- #
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UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL S$ #$$ $($*% $( %+, !( !( +$%)$/$$ (! "!#$%! ! )*(*!% $/ $')$ !', '$ '!% "!#$%! #$( GRUO A& $ '$% $( ALMENDRILLO.
adσ
210 K"2 ad# •
15 K"2
G%+, A BA("$/#%*((,
E
95000 K"2
!%! !((!% (! !%! #$*#, !( +$', +%,+*, '$ #$$ !'"*% (! !'$ = (! !()%! #$ (! '$*/ #$ (! "!#$%!& (! "-*"! $'!#%! $ '$ +$#$ $/,/)%!% $/ / ,'$ ,;$/:
17.5 " ESCUADR1A:
30 "
E( +$', +%,+*, '$%:
P 8
= γ ⋅ b ⋅ h
+ 800 K"3 . 0.175 " . 0.30 " ≈ 42 K" L! !%! ),)!( '$% B'*/ !$%,:
!
= + P8
T 1000 K" 42 K" 1042 K" A,%! '$ #$'$! '!$% !/), #$ (! !%! ),)!( +$#$ !'"*% (! $'!#%! #$ "!#$%!: DEF$*M(CI$N9 L! #$?,%"!*/ !#"*'*($ '$%9 DISEÑO EN ACERO MADERA
!"
!>
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
$ (cm)
ad
2%5
=
%00 2%5
= 254
cm
E( ,$@*$/)$ #$ '$%*#!# #$ #$?,%"!*/ $' #$ 1.5 ! 2& +,% (, '$ !'"$ / ;!(,% #$ 1.6& +,% (, )!/),:
C,e@ f =
ad
ad
⇒ =
C,e@ f
=
254 1*
= 15D cm
L! Q$! $ +%,#$ (! !%! '$%:
m
=
5 ⋅ ⋅ $4 3/4 ⋅ m ⋅ I
= 15D =
5 ⋅ m ⋅ %00 4 3/4 ⋅ D5000 ⋅
∴
T ] "
1%5 ⋅ 303
⇒ m = 1D0 B&cm
12
REFORYAR
! 1042 190 852 K" N$$'!%*!"$/)$ #$$ %$?,%!%'$ (! $'!#%!& +$' $((! ',(! /, $' !+! #$ %$'*')*% ! (! !%! ),)!(. C,/)*/!%$",' $( $$%**, ',(!"$/)$ +,% ",)*;,' !!#"*,'& +$' $ $' )!/ %!/#$ (! !%! $ #$$ !'"*% $( !$%, $/ +%,+,%*/ ! (! "!#$%! B%$(!*/ !+%,-*"!#! #$ 4 ! 1 $ '$%! +%$?$%*($ ,/')%*% (! ;*! #$ ,)%, "!)$%*!( BC,/%$), +%, , !$%, +%,. G$/$%!("$/)$ / $/ %$?$%, #$ !$%, #$$ %*% ,", "-*", $( 50 #$ (! !%! ),)!(. E($*",' $( ', #$ +(!/!' +!%! $( %$?$%,:
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!@
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
'a$ra ($r%!s
.
(la%&has
12*+
e = 1 " = 04 cm 4
A,%! '$ #$$ $($*% $'+$',% #$ +(!/!: E( ","$/), #$ */$%*! $' !?$)!#, +,% !#! /! #$ (!' +(!/!' #$ !$%,.
a
=
5 ⋅ a ⋅ $4 3/4 ⋅ a ⋅ I
5 ⋅ /52 ⋅ %00 4
= 15D =
3/4 ⋅ 21 × 10 ⋅ 2 ⋅
04 ⋅ h a
3
⇒ h a = 53cm > h m = 30cm
12
L! !()%! #$( !$%, '+$%! ! (! !()%! #$ (! "!#$%! $ *"+,'**(*)! , +,% (, "$/,' #*@()! $( +%,$', ,/')%)*;,& !#$"' #$ $ ),#!;! /, $')! ,/'*#$%!#, $( +$', #$( !$%,. γ CO
= %/50 B&m 3
+ 2. 0.0064 " . 0.53 ". 7850 K"3 = 53.25 K" TOTAL≈ 1100 K" E/),/$' /,' ;$",' $/ (! /$$'*#!# #$ !"*!% #$ $'!#%! #$ (! ;*! #$ "!#$%!& +!%! $', #*%$",' */**!("$/)$ $ (! "!#$%! ',+,%)!% $( 50 #$ (! !/)$%*,% !%! ),)!( = ,/ $')! !+%,-*"!*/ '!!%$",' (,' ;!(,%$' #$ (! !'$ = (! !()%! #$ (! ;*!.
m
=
5 ⋅ m ⋅ $4 3/4 ⋅ m ⋅ I
= 15D =
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5 ⋅ 550 ⋅ %00 4 b ⋅ h a 3/4 ⋅ D5000 ⋅ 12
3
⇒
b ⋅ h 3 12
= 113/3424 cm 4
!A
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL S')*)=$/#, (! %$(!*/ #$ $'!#%! +)*"!: b ⋅ (1%3 ⋅ b) 3
= 113/3424 cm 4 ⇒ b = 22** cm
12
E/),/$':
25 "
ESCUADR1A:
+ 800 K"3 . 0.25 " . 0.45 " 90 K" L! !%! ),)!( '$% B'*/ !$%,:
!
= + P8
T 1000 K" 90 K" 1090 K"
L! Q$! $ +%,#$ (! !%! '$%:
m
=
5 ⋅ ⋅ $4 3/4 ⋅ m ⋅ I
= 15D =
5 ⋅ m ⋅ %00 4 3/4 ⋅ D5000 ⋅
∴
T ] "
25 ⋅ 453
⇒ m = D1% B&cm
12
REFORYAR
! 1090 917 173 K" !%! (! $'!#%! #$ (! !'! (! "!#$%! %$'*')$ $( 84.12 #$ (! !%! ),)!( '*/ ),"!% $/ $/)! ),#!;! $( +$', #$( !$%,.
a
=
5 ⋅ a ⋅ $4 3/4 ⋅ a ⋅ I
5 ⋅115 ⋅1%3 ⋅ %00 4
= 15D =
3/4 ⋅ 21× 10 ⋅ 2 ⋅
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04 ⋅ h a 12
3
⇒ h a = 32%cm ⇒ sa= h a = 35cm
!B
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL E/ (! !/)$%*,% $!*/ '$ $')! "!=,%!/#, $/ / 15 (! !%! #$( !$%, ,/ ,$), #$ ),"!% $/ $/)! $( +$', +%,+*, #$( "*'",. A/$ (,' $($"$/),' #$( #$)!(($ ,/')%)*;, '$ $')#*!%/ #$ ?,%"! "' +%,?/#! $/ (,' +%-*",' !+)(,'& ! "!/$%! #$ */)%,#*/ '$ +%$'$/)! (,' #$)!(($' #$ /*/ #$ ;*! %$?,%!#!. S$ '!%/:
L,/*)# +$%/, 30 ". $%/,'
D*"$)%, +$%/, ^
L! +(!/! #$ !$%, '$ $-)$/#$% /! #*')!/*! # ! !#! (!#, #$( $/)%, (/$! #$ (! ;*!& $')! #*')!/*! +$#$ !((!%'$ $-!)!"$/)$ #$ (! )$,%! #$ (!' #$?,%"!*,/$'& '*/ $"!%,& '$ )*$/$: d=
1 $ 1 %00
=
3 2 3 2
= 11% ≅ 120 cm
S$ +$#$ #$)$%"*/!% $-!)!"$/)$ $')! #*')!/*! +,% (! )$,%! #$ (!' #$?,%"!*,/$': D,/#$:
∂2' ⋅I⋅ 2 = ∂ !%! (! ,/#**/ #$ !%!& $( ","$/), $/ ?/*/ #$ - '$%: =
⋅$⋅ 2
−
⋅ 2 2
E/),/$':
∂2' ⋅ $ ⋅ ⋅ 2 − ⋅I⋅ 2 = 2 2 ∂ I/)$%!/#,:
∂' ⋅ $ ⋅ 2 ⋅ 3 ⋅I⋅ = − + C1 4 * ∂
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"
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL
L$,: ⋅I⋅ ' =
⋅ $ ⋅ 3
−
12
⋅ 4 24
+ C1 ⋅ + C 2
!((!",' C1 = C2 ,/ (!' ,/#**,/$' #$ ,%#$: C20 C1
=−
⋅ $3 24
L! $!*/ $/$%!( #$ (! $(')*! '$%: ⋅I⋅' =
⋅ $ ⋅ 3 12
−
⋅ 4 24
−
⋅ $3 ⋅ 24
A,%! '$ #$$ !((!% ! $ #*')!/*! - (! "!#$%! '$ #$?,%"! 1.59 ". !, (! !+(*!*/ #$ (! !%! ),)!( TOTAL 1090 K". ; ;
,t =1-<- 3/# A
# & < + * 1
# & < + * 1
0
:=#
E/),/$' %$$"+(!!/#, $/ (! $!*/ #$ (! $(')*!: D5000 ⋅
25 ⋅ 45 3 12
0454 ⋅ 4
⋅ (−15D) =
10D0 ⋅ %00 ⋅ 3 12
−
10D0 ⋅ 4 24
−
10D0 ⋅ %00 3 ⋅ 24
− *35/3 ⋅ 3 + 155%%D1**% ⋅ - 2/*%5/D/440 = 0
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"1
UNIVERSIDAD JOSE CARLOS MARIATEGUI FACULTAD DE INGENIERIA CIVIL R$',(;*$/#, (! $!*/ +,(*/,"*!(:
D$ (!' !($' '$ #$'!%)!/ (!' #,' <()*"!' +,% '$% ',(*,/$' */,$%$/)$'. E/),/$' # '$% *!(: d
=
2
− 1
=
2
4%/55 - 22135 2
= 12/*
cm
U'!",' $( "!=,% $/)%$ $( !((!#, = $( ;!(,% %$?$%$/*!( #!#, !/)$%*,%"$/)$. # 128.6 _ 130 ".
L! '$+!%!*/ $/)%$ +$%/,' '$% #$ 10 ". E%5+EM( E%T*+CT+*()
" ( 1
= 1.
.+
%ECCI$N T*(N%E*%()9
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