Steel Span- National Steel Bridge Alliance.pdf
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STEEL SPAN WEIGHT CURVES STEEL BRIDGE RESOURCE
Transcript of Steel Span- National Steel Bridge Alliance.pdf
STEEL SPAN
WEIGHT CURVES
STEEL BRIDGE RESOURCE
AISC © 2016
by
American Institute of Steel Construction
All rights reserved. This book or any part thereof must not be reproduced in any form without the
written permission of the publisher.
The AISC and NSBA logos are registered trademarks of AISC.
The information presented in this publication has been prepared in accordance with recognized en-gineering principles. While it is believed to be accurate, this information should not be used or relied upon for any specific application without competent professional examination and verification of its accuracy, suitability and applicability by a licensed professional engineer, designer, or architect. The publication of the material contained herein is not intended as a representation or warranty on the part of the American Institute of Steel Construction or of any other person named herein, that this information is suitable for any general or particular use or of freedom from infringement of any patent or patents. Anyone making use of this information assumes all liability arising from such use.
Caution must be exercised when relying upon other specifications and codes developed by other bodies and incorporated by reference herein since such material may be modified or amended from time to time subsequent to the printing of this edition. The American Institute of Steel Construction bears no responsibility for such material other than to refer to it and incorporate it by reference at the time of the initial publication of this edition.
Printed in the United States of America
The National Steel Bridge Alliance strives to deliver high quality information for use by departments of transportation and designers alike. To that end, NSBA has created a series of steel bridge design resources. The information in these resources was developed by NSBA staff in conjunction with in-dustry professionals. The resources are intended to serve as a starting point for steel bridge design.
Steel Span Weight Curves is the first of these design aids. We plan to periodically update and refine the information in these resources based on the feedback we receive from designers, owners and constructors.
NSBA is proud of the steel bridge industry and looks forward to maintaining its tradition of excel-lence in steel bridge construction.
Bill McEleneyManaging DirectorNational Steel Bridge Alliance
STEEL SPAN
WEIGHT CURVES
NSBA STEEL SPAN WEIGHT CURVES 1
Assumptions• Section is designed as composite.• Girders are assumed continuous.• Design considers fatigue loading.• Span lengths are based upon the maximum span distance. Where more than one span exists, use the maxi-
mum span to determine span weight.• Trend line value represents the line of best fit based upon the discrete values.• Shaded area represents deck areas in which 68% of the sample bridges are located.• Both curved and straight girders are included in the curves.
SHOULDERPARAPET WIDTH
OVERALL BRIDGE WIDTH
TOTAL LANE(S) WIDTH SHOULDER PARAPET WIDTH
OVERHANG(VARIES)
GIRDER SPACING (VARIES)OVERHANG (VARIES)
BR
IDG
E D
EC
K
BRIDGE GIRDER (TYP)
TYPICAL BRIDGE SECTIONN.T.S.
WE
AR
ING
S
UR
FAC
E
These graphical design aids are intended to be used during the preliminary phases of design for evaluation of alter-native structures to quickly determine the relative costs of various girder spacings and number of girder spans. The curves have been constructed from cost-effective conceptual solutions that NSBA has prepared. They represent the predicted pounds of steel per square foot for various span lengths and girder spacings for single spans, two spans, and three or more spans.
Design ParametersThese curves represent predicted pounds of steel per square foot derived from data from more than 800 NSBA con-ceptual solutions optimized for economical bridge designs. Every bridge is unique and other factors can influence the design, resulting in values outside the ranges shown in these curves. Care should be taken to ensure that an appropriate analysis is conducted. The figure below represents a typical bridge section view.
About the Span Curves
2 NSBA STEEL SPAN WEIGHT CURVES
0
20
40
60
80
100
120
140
160
50 75 100 125 150 175 200 225 250 275 300 325 350
Ste
el w
eig
ht
per
sq
uare
fo
ot
of
bri
dg
e d
eck
surf
ace
(psf
)
Span (ft)
Single Span — All Girder Spacing
Trendline
0
20
40
60
80
100
120
140
160
50 75 100 125 150 175 200 225 250 275 300 325 350
Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Single Span — 7' to 9' Girder Spacing
Trendline
Single-Span Bridges
NSBA STEEL SPAN WEIGHT CURVES 3
0
10
20
30
40
50
60
70
80
90
50 75 100 125 150 175 200 225 250 275
Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Single Span — 9' to 11' Girder Spacing
Trendline
0
10
20
30
40
50
60
70
80
90
100 125 150 175 200 225 250 275
Ste
el w
eig
ht p
er s
qu
are
foo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Single Span — 11' and Greater Girder Spacing
Trendline
Single-Span Bridges
4 NSBA STEEL SPAN WEIGHT CURVES
0
20
40
60
80
100
120
50 75 100 125 150 175 200 225 250 275 300 325 350
Ste
el w
eig
ht
per
sq
uare
fo
ot
of
bri
dg
e d
eck
surf
ace
(psf
)
Span (ft)
Two Span — All Girder Spacing
Trendline
0
10
20
30
40
50
60
50 75 100 125 150 175Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f bri
dg
e d
eck
surf
ace
(psf
)
Span (ft)
Two Span — 7' to 9' Girder Spacing
Trendline
Two-Span Bridges
NSBA STEEL SPAN WEIGHT CURVES 5
0
10
20
30
40
50
60
50 75 100 125 150 175 200 225Ste
el w
eig
ht
per
sq
uare
fo
ot
of
bri
dg
e d
eck
surf
ace
(psf
)
Span (ft)
Two Span — 11' and Greater Girder Spacing
Trendline
0
10
20
30
40
50
60
50 75 100 125 150 175 200 225Ste
el w
eig
ht
per
sq
uar
e fo
ot
of b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Two Span — 9' to 11' Girder Spacing
Trendline
Two-Span Bridges
6 NSBA STEEL SPAN WEIGHT CURVES
0
10
20
30
40
50
60
70
80
90
50 75 100 110 115 125 135 150 165 175 200 220 230 250 275 300 325 350 400 450
Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Three or More Spans — All Girder Spacing
Trendline
0
10
20
30
40
50
60
70
80
90
50 75 100 125 135 150 175 200 230 250 275 300
Ste
el w
eig
ht p
er s
qu
are
foo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Three or More Spans — 7' to 9' Girder Spacing
Trendline
Three-or-More-Span Bridges
NSBA STEEL SPAN WEIGHT CURVES 7
0
10
20
30
40
50
60
70
80
90
50 75 100 110 125 135 150 165 175 200 220 250 275 300 325 350 375
Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Three or More Spans — 9' to 11' Girder Spacing
Trendline
0
10
20
30
40
50
60
70
80
90
100 125 135 150 165 175 200 220 230 250 275 300 325 350 425 450Ste
el w
eig
ht p
er s
qua
re f
oo
t o
f b
rid
ge
dec
k su
rfac
e (p
sf)
Span (ft)
Three or More Spans — 11' and Greater Girder Spacing
Trendline
Three-or-More-Span Bridges
National Steel Bridge Alliance(a division of American Institute of Steel Construction)One East Wacker Drive, Suite 700Chicago, Illinois 60601
312.670.2400 www.steelbridges.org
Steel: The Bridge Material of Choice.
NSBA-021
