composite floor beam - structural design...
TRANSCRIPT
PROJECT : PAGE :
CLIENT : DESIGN BY : JOB NO. : DATE : REVIEW BY :
Composite Beam Design with Verco Floor Deck Based on AISC Manual 9th
INPUT DATA & DESIGN SUMMARYBEAM SECTION = > W30X132 = > A d
38.9 30.3 5770 380FLOOR DECK TYPE = > W3-6 1/4" LW
RIBS PERPENDICULAR TO BEAM ? Yes (perpendicular)BEAM SPAN 52 ftBEAM SPACING (TRIB. WIDTH) 16 ft, o.c.
SUPERIMPOSED LOAD 246BEAM YIELD STRESS 50 ksi
CONCRETE STRENGTH 3 ksi
SHEAR STUD DIA. (1/2, 5/8, 3/4) 3/4 in
NUMBER OF STUD IN ONE RIB 1( Total 160 - 3/4 x 4.5" Shear Studs Required)
( 0 13/16 in camber suggested) THE BEAM DESIGN IS ADEQUATE.
ANALYSISCHECK DIMENSION REQUIREMENTS (AISC-ASD I5.1, page 5-61)
3.25 in > 2 in [Satisfactory]
3 in < 3 in [Satisfactory]
3/4 in < 3/4 in [Satisfactory]
4.5 in > 3 in [Satisfactory]4 in o.c. < 36 in o.c. [Satisfactory]
6 in > 2 in [Satisfactory]
DETERMINE COMPOSITE PROPERTIES
MIN ( L / 4 , B ) = 156 in, (AISC-ASD I1.1, page 5-56)
13.91 , (ACI 8.5.1)
36.5
24.7 in, from steel bottom.
13161
532
1112
CHECK BENDING & SHEAR CAPACITIES
246.00 43.50 + 8.27 ) = 297.77
1610 ft-kips, (changeable). 124 kips, (changeable per actual).
Bottom: 39 ksi < 45 ksi, (non-shored, AISC-ASD I2.2, page 5-57)[Satisfactory]
Top: 1.249 ksi < 1.35 ksi, (AISC-ASD I2.2, page 5-57)[Satisfactory]
Shear: 6.648 ksi < 20 ksi [Satisfactory](neglecting concrete & steel deck capacity conservatively)
Ix Sx
L =B =
ws = lbs / ft2
Fy =
fc'=f =
Nr =
t0 =
hr =
f =
Hs = hr + 1.5 =s =
wr =
b =
Actr = b t0 / n = in2
in4
in3, referred to steel bottom.
in3, referred to concrete top.
w = ws+ wwt= + ( lbs / ft2 (total gravity loads)
0.9 Fy =
0.45 fc' =
En
Ec
00.5 0.5ctr
ctr
rb
d Adh tAyAA
2 22 0
00.5 0.512ctr
tr x ctr rb btAd d yyA tI I A h
trtr
b
IS
y
0
trt
r b
IS
yd h t
DL LL
bx tr
M Mf
S S
maxc
t
Mf
nS
maxv
w
Vf
d t
0.4F y
2
max8
wBLM max
2
wBLV
(cont'd)CHECK SHEAR CONNECTOR CAPACITY
646.425 kips, (AISC-ASD I4-1 & I4-2, page 5-58)
532
646.425 kips, (AISC-ASD I2-1 & I4, page 5-57 & 58)
0.850 < 1.0 , (AISC-ASD I5-1, page 5-61)
8.11 kips, (AISC-ASD I5.2, page 5-61)
Allowable Horizontal Shear Load for One Connector (q, kips)(AISC-ASD Table I4.1 with coefficient Table I4.2, page 5-59)
( in ) ( in ) 3.0 3.5 4.0 or Larger0.500 1/2 2 4.2 4.6 4.90.625 5/8 2 1/2 6.6 7.1 7.60.750 3/4 3 9.5 10.4 11.0
160 , total number on the beam for partial composite action.
160 , total number on the beam for full composite action.
160 , total number required on the beam, (AISC-ASD I4, page 5-59)
CHECK INITIAL DEFLECTION / CAMBER AND STRESS ON NON-COMPOSITE (AISC-ASD I2.1, page 5-56)
100% Self Wt = 0.83 kips / ft (100% self weight load only)
0.81 in, Camber Suggested
9 ksi < 33 ksi[Satisfactory]
CHECK LIVE LOAD DEFLECTION ON COMPOSITE (AISC-ASD I2.1 page 5-56 & page 2-249)
3.94 kips / ft (live load only)
13161
1.70 in < L / 360 = 1.73 in[Satisfactory]
Note:The STUDS SPACING must be based on actual deck ribs spacing for perpendicular to beam. For the following total [15] studs, if ribs spacing
12" o. c., the minimum composte beam capacity is from2 rows @ 12" o.c., not one row @ 8.57" o.c. See software
for more information.
Technical References: 1. AISC: "Manual of Steel construction 9th", American Institute of Steel Construction, 1990. 2. Alan Williams Ph.D., S.E., C.Eng.: "Structural Steel Design - Volume 1: ASD", ICBO, 2001.
Seff = Min[ Mmax / (0.66 Fy) , Str ] = in3, referred to steel bottom.
q' = r q =
Dia. f min. Hs Concrete fc'
2 N1' = 2 Vh' / q' = 2 N1 = 2 Vh / q' =
n = MIN[ MAX(2N1' , 2N1/4) , 2N1] =
wDL=
0.66 Fy =
wLL=Ieff= in4 (AISC-ASD, I4-4)
CompositeFloorBeamWithCantilever.xls on the websitewww.Engineering-International.com
'0.85 / 2 / 2,c y sh cfMINV A F A
2' , 0.25eff sh h
tr s
S SMAXV V
S S
0.85 1.0 ,
0.6 1.0 , & 1.5
w H sr for Perpendicularh hN r rr
w H wsr rfor Parallelh h hr r r
r
45
384
DLDL
w L
EI x
2
8
DL
bx
w Lf
S
45
384
LLLL
w L
EIeff
PROJECT : PAGE :
CLIENT : DESIGN BY : JOB NO. : DATE : REVIEW BY :
Composite Beam Design with Formed Steel Deck Based on AISC-ASD
INPUT DATA & DESIGN SUMMARYBEAM SECTION = > W21X62 = > A dBEAM SPAN 40 ft 18.3 21.0 1330 127BEAM SPACING (DECK SPAN) 11 ft, o.c.
DEAD LOAD 125LIVE LOAD 80RIBS PERPENDICULAR TO BEAM ? yes (perpendicular)
BEAM YIELD STRESS 50 ksi
CONCRETE STRENGTH 4.5 ksi
TOPPING CONCRETE THICK. 3 in
SHEAR STUD DIA. (1/2, 5/8, 3/4) 5/8 in
NOMINAL RIB HEIGHT 2 in
AVERAGE WIDTH OF RIB 3 in
NUMBER OF STUD IN ONE RIB 1( Total 34 - 5/8 x 3.5" Shear Studs Required)
( 2 1/16 in camber suggested) THE BEAM DESIGN IS ADEQUATE.
ANALYSISCHECK DIMENSION REQUIREMENTS (AISC-ASD I5.1, page 5-60)
3 in > 2 in [Satisfactory]
2 in < 3 in [Satisfactory]
5/8 in < 3/4 in [Satisfactory]
3.5 in > 2.5 in [Satisfactory]15 in o.c. < 36 in o.c. [Satisfactory]
3 in > 2 in [Satisfactory]
DETERMINE COMPOSITE PROPERTIES
MIN ( L / 4 , B ) = 120 in, (AISC-ASD I1.1, page 5-56)
7.58 , (ACI 8.5.1)
47.5
20.6 in, from steel bottom.
3954
192
733
CHECK BENDING & SHEAR CAPACITIESw = 205
451 ft-kips, (changeable). 45 kips, (changeable per actual).
Bottom: 37 ksi < 45 ksi, (non-shored, AISC-ASD I2.2, page 5-57)[Satisfactory]
Top: 0.974 ksi < 2.025 ksi, (AISC-ASD I2.2, page 5-57)[Satisfactory]
Shear: 9.127 ksi < 20 ksi [Satisfactory](neglecting concrete & steel deck capacity conservatively)
Ix Sx
L =B =
wDL = lbs / ft2
wLL = lbs / ft2
Fy =
fc'=t0 =
f =
hr =
wr =
Nr =
t0 =
hr =
f =
Hs = hr + 1.5 =s =
wr =
b =
Actr = b t0 / n = in2
in4
in3, referred to steel bottom.
in3, referred to concrete top.
lbs / ft2 (total gravity loads)
0.9 Fy =
0.45 fc' =
29000'57
En
Ec f c
00.5 0.5ctr
ctr
rb
d Adh tAyAA
2 22 0
00.5 0.512ctr
tr x ctr rb btAd d yyA tI I A h
trtr
b
IS
y
0
trt
r b
IS
yd h t
maxc
t
Mf
nS
2
max8
wBLM max
2
wBLV
maxv
w
Vf
d t 0.4F y
DL LL
bx tr
M Mf
S S
maxv
w
Vf
d t
(cont'd)CHECK SHEAR CONNECTOR CAPACITY
457.5 kips, (AISC-ASD I4-1 & I4-2, page 5-58)
164
148.62 kips, (AISC-ASD I2-1 & I4, page 5-57 & 58)
0.956 < 1.0 , (AISC-ASD I5-1, page 5-61)
8.80 kips, (AISC-ASD I5.2, page 5-61)
Allowable Horizontal Shear Load for One Connector (q, kips), (AISC-ASD Table I4.1, page 5-59)
( in ) ( in ) 3.0 3.5 4.0 or Larger0.500 1/2 2 5.1 5.5 5.90.625 5/8 2 1/2 8.0 8.6 9.20.750 3/4 3 11.5 12.5 13.3
34 , total number on the beam for partial composite action.
104 , total number on the beam for full composite action.
34 , total number required on the beam, (AISC-ASD I4, page 5-59)
CHECK INITIAL DEFLECTION / CAMBER AND STRESS ON NON-COMPOSITE (AISC-ASD I2.1, page 5-56)
1.38
2.05 in, Camber Suggested
26 ksi < 33 ksi[Satisfactory]
CHECK LIVE LOAD DEFLECTION ON COMPOSITE (AISC-ASD I2.1 page 5-56 & page 2-249)
0.88 kips / ft (live load only)
2826
0.62 in < L / 360 = 1.33 in[Satisfactory]
Technical References: 1. AISC: "Manual of Steel construction 9th", American Institute of Steel Construction, 1990. 2. Alan Williams Ph.D., S.E., C.Eng.: "Structural Steel Design - Volume 1: ASD", ICBO, 2001.
Seff = Min[ Mmax / (0.66 Fy) , Str ] = in3, referred to steel bottom.
q' = r q =
Dia. f min. Hs Concrete fc'
2 N1' = 2 Vh' / q' = 2 N1 = 2 Vh / q' =
n = MIN[ MAX(2N1' , 2N1/4) , 2N1] =
wDL= kips / ft (dead load only)
0.66 Fy =
wLL=Ieff= in4 (AISC-ASD, I4-4)
'0.85 / 2 / 2,c y sh cfMINV A F A
0.85 1.0sr
r rr
w Hh hN
r
2' , 0.25eff sh h
tr s
S SMAXV V
S S
45
384
DL
DLw L
EI x
2
8
DL
bx
w Lf
S
45
384
LLLL
w L
EIeff