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GUSSET PLATES IN RAILROAD TRUSS BRIDGES –
FINITE ELEMENT ANALYSIS AND COMPARISON
WITH WHITMORE TESTING
Walid S. Najjar, Ph.D., P.E.1, Frank DeOrtentiis, P.E.
WSP ▪ SELLS 555 Pleasantville Road, Briarcliff Manor, New York, 10510, U.S.A.
914-747-1120 (phone) / 914-747-1956 (fax) / www.wspsells.com
(1) Member of AREMA Committees 8 and 15
ABSTRACT
An effective simple procedure for two-dimensional finite element analysis of gusset plates
in truss bridges is presented. Gusset and splice plates are modeled with plate elements and
truss members are modeled with line or frame elements. While the focus is on gusset plates
in railroad truss bridges, the procedure is applicable to gusset plates in highway truss
bridges and other types of gusset plate connections. Results from finite element analysis
validate key conclusions of the historic and still relevant experimental investigation of
stresses in small-scale gusset plates by R. E. Whitmore, pending current large-scale gusset
plate testing at the FHWA TFHRC Structures Laboratory. A distribution angle of 30
degrees, the basis of the so-called Whitmore section, provides reasonable estimate of
stress. Maximum normal stress along a horizontal section immediately above a bottom
chord is located slightly away from the edge of a gusset plate, instead of at the edge as
predicted by simple beam theory. And maximum shear stress is located near the center of
the plate, consistent with that theory.
A Mathcad work sheet has been developed for analysis and evaluation of gusset plates in
railroad truss bridges, by modifying a NYSDOT template to include AREMA MRE
applicable requirements and Committee 15 new requirements on gusset plates. Simple
beam theory is assumed for calculating stresses on horizontal and vertical critical sections
of a gusset plate. The Whitmore section is assumed for distribution of normal load from a
truss member onto a gusset plate.
Outlined in this paper is the development of the finite element analysis and the Mathcad
analysis.
Key Words: Gusset Plates, Railroad Bridge, Mathcad Analysis, Finite Element Analysis,
Load Rating.
INTRODUCTION
Much has been said and written about truss gusset plates, since the unfortunate collapse of
the I-35 Bridge over the Mississippi River. A list of key references (1 to 7) on gusset plate
analysis, design, and evaluation are provided. The intent of this paper is to present a simple
and effective methodology for analysis and evaluation of gusset plates in railroad truss
bridges. While the Mathcad part of the methodology is partly focused on railroad bridges,
the structural analysis part is entirely applicable to both railroad and highway truss bridges.
Two-dimensional structural modeling and analysis of a typical Warren truss is presented.
The truss model has realistic geometry and sectional properties for a railroad bridge and
consists of beam elements for truss members and finite elements for gusset plate
connections. Analysis results are compared to experimental stress results from the
landmark research by R. E. Whitmore (1). After almost 60 years, the Whitmore testing of a
small-scale model of a truss joint connected by gusset plates continues to be the key
reference in available literature on structural behavior of gusset plates. Currently at the
FHWA TFHRC Structures Laboratory and as part of NCHRP Project 12-84 (4), full-scale
gusset plates are being tested. However at this time, there is no publicly available
information on the progress of this testing.
DEVELOPMENT OF THE STRUCTURAL MODEL
A Warren type truss has been selected as the subject structure for this research, because it
is considered one of the most common types of bridge trusses, and the Whitmore testing
was done on a small model of a Warren truss joint. Shown in Figure 1 is the subject truss
with an enlarged view of Joint L2 connection. This is a simple span truss, consisting of 14
equal panels, a span length of 542 feet and truss depth of 84 feet. Its geometry and
sectional properties are consistent with the properties of a realistic railroad bridge. The
enlarged view shows only perimeter rivets connecting the gusset plate to the bottom chord,
two diagonal and vertical members of the truss. These rivets are shown to the exclusion of
many other rivets, because their location is used to define the model width of truss
members within the connection and for simplicity of presentation. Gusset plate dimensions
are 124 inches for width, 103 inches for height, and 13/16 inches for thickness. There are
two plates per joint.
In contrast, the tested Whitmore model connection was based on Joint 2 of a Warren truss,
consisting of 10 equal panels, a span length of 295 feet and truss depth of 43.5 feet. Even
though that truss was a highway bridge truss, comparison to the subject railroad truss in
terms of structural modeling and analysis is valid. Structural behavior of a gusset plate in
response to a moving load, modeled as a series of concentrated loads that are applied
U7
14 x 38.71' = 542'
L0 L1 L2 L3 L4 L5 L6 L7 L'6 L'5 L'4 L'3 L'2 L'1 L'0
U1 U2 U3 U4 U5 U6 U'6 U'5 U'4 U'3 U'2 U'1
84'52.3'
Figure 1: Subject Warren Truss and Joint L2 Gusset Plate (Shown Perimeter Rivets Only)
strictly at truss joints, is a function of relative member stiffnesses and resulting internal
forces, regardless of the load type.
Figure 2 shows a two-dimensional model of the subject truss with Joint L2 gusset plate
connection. Beam (line) elements represent all truss members (chords, diagonals and
verticals), and plate elements represent the gusset plate as well as segments of the truss
member that frame into the joint. The width of such segment is assumed to be the
perpendicular distance between the two rows of edge rivets that are parallel to the framing
truss member. The thickness of the segment is calculated by dividing the area of the truss
member by the segment width.
While only one joint is represented by plate elements in this particular model, more or all
joints could be represented in the same manner and within the same model. Quadrilateral
elements are used primarily for the framing segments of truss members and the horizontal
zone of the gusset plate above the bottom chord. For the remaining areas of the gusset
plate, a combination of quadrilateral and triangular (three-node) elements are used as
necessary based on the local geometry. Structural modeling and analysis is done through
the latest version of the software program STAAD.Pro (8). The mesh generation capability
of this software is utilized, especially for the quadrilateral elements, which makes the
modeling effort reasonably easy. The master-slave command of the program is used to
model an assumed rigid transition from a beam element to plate elements. Edge nodes
along the equivalent width of a framing truss member are assumed to be rigidly linked to
the connecting interface node.
ANALYSIS RESULTS AND COMPARISON WITH WHITMORE TEST RESULTS
Live load forces in truss members at Joint L2 are shown in Table 1 for various load cases,
including (i) maximum tension or compression in a particular member with corresponding
force in other members and (ii) maximum tension or compression in each member. Tensile
forces are shown as positive values, while compressive forces are shown as negative
values. The first load case (LC 1) is the most critical because of concurrent maximum
L1-L2 L2-L3
L2-U1 L2-U3 L2-U2
Figure 2: Structural Model of the Subject Truss and Joint L2 Gusset Plate
tension in both chord members and close to maximum forces in the two diagonals. Gusset
plate stresses at Joint L2 are shown in subsequent figures for only this dominant load case.
It is worthy to compare member force ratios for this load case to the Whitmore force ratios,
as shown in Table 2, in order to justify subsequent comparisons on stress distributions and
locations of maximum stresses. Each force is divided by the maximum force in the group
(or load case), which occurs in chord member L2-L3 for both groups; the ratio for this
member is one. For the tension chord (L1-L2), the ratio is 0.53 for Load Case 1 and 0.58
for Whitmore testing. For the compression diagonal (L2-U3), the ratio is 0.34 for Load
Case 1 and 0.30 for Whitmore testing. The force ratios for each of these members are close
in value, except for the tension diagonal (L2-U1).
Load Cases
Truss Member Forces, kips
L1-L2 L2-U1 L2-U2 L2-U3 L2-L3LC 1 1491 1445 10 -960 2821LC 13 309 47 5 137 269LC 14 105 -33 1 35 67LC 26 1182 1398 6 -1097 2552LC 27 1386 1478 10 -996 2754Maximum 1491 1478 10 137 2821
Minimum 105 -33 1 -1097 67
Table 1: Live Load Member Forces at Truss Joint L2
L1-L2 L2-U1 L2-U2 L2-U3 L2-L3
Load Case 1 Force 1491 1445 10 960 2821 Ratio 0.53 0.51 0 0.34 1.00
Whitmore Test
Force 12.48 7.43 0 6.53 21.6
Ratio 0.58 0.34 0 0.30 1.00
Table 2: Comparison of Joint 2 Forces with Whitmore Test Forces
It is reasonable to state that most of the force ratios within Load Case 1 are approximately
equal to the Whitmore testing forces ratios. This is significant considering the fact that a
full scale truss and gusset plate model has been analyzed, whereas a small scale model of a
gusset plate was tested by Whitmore, in addition to differences in truss geometry and
relative axial rigidities of truss members.
Principal tensile (major) stress contours at Joint L2 are shown in Figure 3. At the end of
diagonal member L2-U1, there is a zone of high tensile stress in the gusset plate, shown as
a green color. The location of this stress zone is consistent with the Whitmore test results.
The highest tensile stresses, shown as yellow and red colors, are located at the interface
corner zones between truss members especially chord L1-L2 and the gusset plate.
0.5
29 KSI
L1-L2 L2-L3
L2-U2 L2-U3 L2-U1
High Stress
Stress Concentration
PSI
Figure 3: Principal Tensile Stress Contours at Joint L2
There is high stress concentration in these zones, primarily due to simplifying assumptions
in the model. For instance, rivets are not modeled and therefore stress is transferred totally
at the interface from a truss member to the gusset plate, instead of gradually through the
rivets in an actual joint or a three-dimensional model of a joint. Various interface modeling
schemes have been tried to determine the extent of this stress concentration. When edge
nodes of an interface line are removed from the master-slave list, for example at the bottom
chord interface, the highest stress zone is moved away from the gusset plate and into the
bottom chord segment within the joint. But when the interface master joint of chord L2-L3
is moved away from the edge of the gusset plate and into the chord, requiring additional
plate elements to model the chord, a stress concentration zone remains at the same location
as in Figure 3. Without further research, including laboratory test verification, a firm
conclusion on the observed stress concentration could not be drawn. The Whitmore testing
did not address this issue, but that does not necessarily mean it is a realistic concern or the
other way around.
Figure 4 shows the Whitmore section width at the end of diagonal member L2-U1. This
width is determined by drawing a line starting from each corner rivet in the first row of the
member, along an angle of 30 degrees with respect to member axis, and extending the two
lines until they intersect a third line drawn through the bottom row of rivets. For this case
however, the width is limited by the proximity of rivets in adjacent members. When the
diagonal member is modeled to be shorter in length within the joint, angular divergence or
distribution of tensile stress becomes even more obvious. It is interesting to note that based
on the report of R. E. Whitmore (1), the angle of 30 degrees was commonly used at that
time, implying that it was validated and not initiated by this historic testing.
The estimated Whitmore section width for the case shown in Figure 4 is 43.2 inches. A
tensile distributed stress of 20.6 ksi on this section is calculated, based on the estimated
width, total gusset plate thickness of 1.625 inches and a tensile force of 1445 kips in
diagonal member L2-U1. This stress value is approximately equal to the finite element
stress of 20.1 ksi shown in green color in Figure 3.
Principal compressive (minor) stress contours at Joint L2 are shown in Figure 5. A zone of
high compressive stress in the gusset plate is shown at the edge of diagonal member L2-
U3, as blue and dark blue colors. This observation is also consistent with the Whitmore
testing. There is divergence of compressive stress; but given the proximity of the diagonal
to the vertical and the tapering of the diagonal as shown in Figure 1, no conclusion could
be drawn on a divergence angle.
30o
30o
W
Figure 4: Whitmore Section Width at the End of Diagonal Member L2-U1
However, when modifying the model by shortening the length of the diagonal segment
within the gusset plate, stress distribution could be defined with a divergence angle of
approximately 30 degrees, as suggested by Whitmore.
Another key observation is the vertical zone of high compressive stress at the edge of the plate near diagonal member L2-U3. There is a steady decrease in compressive stress along the plate edge, starting at the top and moving downwards to chord member L2-L3. This is significant because when checking edge compressive stress for gusset plate design or evaluation, a maximum normal stress is calculated at the plate edge along a horizontal plane above the chord and the stress is assumed to exist along the vertical edge of the plate.
-19.3
4.4 KSI
L1-L2 L2-L3
L2-U2 L2-U3 L2-U1
High Stress
Stress Concentration
PSI
Figure 5: Principal Compressive Stress Contours at Joint L2
Shown in Figure 6 are principal shear stress contours at Joint L2. There is a zone of
maximum shear stress in the gusset plate, shown in yellow and green colors along a
horizontal plane above the bottom chord, extending from plate edge above member L2-L3
to below diagonal member L2-U1. Again this observation is consistent with the Whitmore
testing. The highest shear stress shown in red color is due to stress concentration, given the
assumptions in the model and as explained for the principal tensile stress contours.
Local shear stress along a horizontal section above the bottom chord is shown in Figure 7.
For a typical design or evaluation of a gusset plate, this shear stress is calculated by
assuming uniform distribution of the sum of the horizontal force components of the two
diagonal members.
0.2
14.4 KSI
L1-L2 L2-L3
L2-U2 L2-U3 L2-U1
High Stress
Stress Concentration
PSI
Figure 6: Principal Shear Stress Contours at Joint L2
For the primary load case (LC 1), the sum of the horizontal force components is 1325 kips.
The area of the horizontal section is the plate width (124 inches) multiplied by the plate
thickness (13/16 inches). With two plates resisting member forces, the average shear stress
on the horizontal plane is about 6600 psi, which is consistent with the shear stress shown in
Figure 7.
Local normal stress along the same horizontal section above the bottom chord is shown in Figure 8. Compressive and tensile stresses are shown respectively below and above the horizontal distance axes. Few observations are noteworthy. First, there is high tensile stress at the plate edge connected to chord member L2-L3, where compression is expected. This discrepancy is related to the observed concentration of principal tensile stress shown in Figure 3. The previous discussion of stress concentration applies to both principal and normal stresses. Second, there is tensile stress near chord member L1-L2 and along a horizontal projection of diagonal member L2-U1, as expected.
KSI
12
8
4
4
8
12
0
KSI
12
8
4
4
8
12
0
Figure 7: Local Shear Stress on Horizontal Section above Bottom Chord at Joint L2
The location of maximum stress is not at the edge, as predicted from beam theory, but
inside the gusset plate area. This result is consistent with the Whitmore testing, except that
the location of maximum tension is farther away from the edge and below the diagonal
member. Third, a similar observation can be made for normal compressive stress within
the plate, regarding its maximum value and location.
MODELING AND ANALYSIS OF NON-TYPICAL GUSSET PLATE GEOMETRY
The modeling and analysis procedure presented before is applicable to any gusset plate
joint geometry. To demonstrate its versatility, the procedure is applied to a non-typical
gusset plate connection, specifically Joint U1, which has non-rectangular plate geometry
and non-symmetric configuration of four connecting truss members. Joint L2 in contrast
has rectangular plate geometry and approximately symmetric configuration of five
connecting members, which is typical for other lower chord joints such as L4 and L6, each
KSI
9
6
3
3
6
9
0
KSI
9
6
3
3
6
9
0
Figure 8: Local Normal Stress on Horizontal Section above Bottom Chord at Joint L2
with two connecting diagonals. The same can be stated for upper chord joints with five
connecting members, such as U5 and U7.
Figure 9 shows a finite element model of gusset plates at upper chord Joint U1. The same
modeling procedure is applied, whereby (i) rectangular plate elements are used primarily to
represent truss member segments within the joint and (ii) triangular plate elements are used
for other areas of the joint. For each of the four connecting truss members, a rigid link is
provided at the interface between the beam element representing the member and the finite
elements, as described before.
U1-L1
U1-L0
U1-L2
U1-U2
Figure 9: Finite Element Model of Upper Chord Joint U1
Shown in Table 3 are live load forces in truss members at Joint U1 for various load cases,
including maximum tension or compression force in a member with corresponding force in
other members, and maximum tension or compression in each member. Positive values
indicate tensile forces and negative values indicate compressive forces. Load Case 1 is
dominant because of concurrent maximum compression in the upper chord and end post
members and close to maximum forces in the vertical and diagonal members. The force in
diagonal member U1-L2 is slightly different (0.5% less) than the force in the same member
resulting from the analysis for Joint L2. The reason for this insignificant difference is that
each joint is modeled separately, resulting in slightly different length and axial rigidity of
this member.
Gusset plate stresses at Joint U1 are presented for the dominant load case only. Figure 10
shows principal tensile stress contours in Joint U1. There is a high tension zone in the
gusset plate, shown by the colors green and yellow, near the intersection of members U1-
L0 and U1-U2 and above diagonal member U1-L2.
Load Cases
Truss Member Forces, kips
U1-L0 U1-L1 U1-L2 U1-U2LC 1 -2495 292 1438 -2417LC 13 -516 297 45 -345LC 14 -175 148 -34 -87LC 26 -1978 -5 1393 -2072LC 27 -2319 144 1472 -2330Maximum -175 297 1472 -87
Minimum -2495 -5 -34 -2417
Table 3: Live Load Member Forces at Truss Joint U1
This is consistent with the fact that the diagonal member has the highest tensile force,
while members U1-L0 and U1-U2 have almost equal compressive forces that counteract
the tensile force. The noted tensile zone is located between the end of the diagonal member
and the intersection of the compression members. The maximum tensile principal stress in
this zone is about 10 ksi. This value can be checked by assuming the diagonal force to be
distributed over a section along its interior end rivets, which extends to neighboring rivets
in the upper chord and end post and is limited by two lines making 30 degree angles with
the axis of the diagonal. With an estimated distribution width of 50 inches, sum of gusset
plate thickness of 2.75 inches, and tensile force of 1438 kips, a tensile stress of 10.5 ksi is
calculated. Even though this is a normal stress, not a principal stress, it provides a rough
check on the analysis results.
U1-L1U1-L0 U1-L2
U1-U2 1.5
12.9 KSI
High Stress
Stress Concentration
Stress Concentration
PSI
Figure 10: Principal Tensile Stress Contours at Joint U1
There are stress concentrations, shown in Figure 10 in the colors red and yellow, at the
interface between members U1-L2 and U1-U2 and the gusset plate. A discussion of stress
concentration and the effects of modeling assumptions on this behavior are presented
before.
Figure 11 shows principal compressive stress contours in Joint U1. Stress concentrations
are shown in this figure in pink and brown colors, at the gusset plate interface with
members U1-L0 and U1-U2. An elongated zone of maximum compression is shown along
the inside edges of members U1-L0 and U1-U2.
High Stress
Figure 11: Principal Compressive Stress Contours at Joint U1
-12.7
2.5 KSI
PSI
U1-L1U1-L0 U1-L2
U1-U2
Stress Concentration
Principal shear stress contours are shown in Figure 12. The highest shear stress zone in the
gusset plate occurs near the intersection of members U1-L0 and U1-U2 and above diagonal
member U1-L2, and is shown by the colors red and brown. This zone is approximately at
the same location as the zone for high principal tensile stress.
MATHCAD ANALYSIS AND DESIGN CHECKS
A Mathcad work sheet is developed for analysis and evaluation of gusset plates in railroad
truss bridges. It has been achieved by modifying a NYSDOT work sheet template (3) to
include applicable requirements from AREMA Manual of Railway Engineering (9) and
new requirements on gusset plates by AREMA Committee 15. Stresses on horizontal and
vertical critical sections of a gusset plate are calculated by assuming simple beam theory.
U1-L1U1-L0 U1-L2
U1-U2 0.1
8.3 KSI PSI
High Stress
Figure 12: Principal Shear Stress Contours at Joint U1
Truss member forces are distributed along a Whitmore section, as previously described in
this paper.
Figure 13 shows the assumed critical sections on Joint L2. A horizontal section (A-A) is
located above the bottom chord at the location of the lowest rivet or line of rivets. A
vertical section (B-B) is located on one side of the vertical member, along the line of
perimeter rivets. On the other side of the vertical member, another vertical section (C-C) is
assumed in a similar manner.
The analysis part of the Mathcad procedure consists of the following steps:
1. Resolve member forces into horizontal and vertical force components
A A
B
B
C
C
Figure 13: Critical Sections for Mathcad Analysis
2. Calculate properties of each section, specifically area, moment of inertia, neural
axis, section modulus and moment arms
3. Add separately components of axial force, shear force and bending moment,
4. Calculate stresses, specifically axial stress (force divided by area), flexural stress
(moment divided by section modulus), and average shear stress (force divided by
area)
5. Combine axial stress with flexural stress to calculate maximum compression and
tension at plate edges.
Calculations for Load Case 1 on Joint L2 result in the following stresses on the horizontal
section (A-A): an axial tension stress of 1.6 ksi, a flexural stress of 5.3 ksi, and a shear
stress of 6.5 ksi. The axial and flexural stresses are combined (added or subtracted) to
calculate a tension stress of 6.9 ksi at the left edge of the plate (near member L2-L1) and a
compressive stress of 3.7 ksi at the right edge of the plate (near member L2-L3).
In comparison and as shown in Figure 8, the finite element analysis results in the following
local stresses on the critical horizontal section – a tension stress of 2 ksi at plate edge,
maximum tension stress of 8 ksi within the plate, and maximum compressive stress of 5.5
ksi within the plate. The stress concentration at the interface of the gusset plate and
member L2-L3 is not considered, considering previous discussion. A key difference
between the two sets of results is the location of maximum normal stress. Aside from this,
the values of maximum stress calculated through Mathcad are 14% less for tension and
33% less for compression, as compared to the finite element analysis.
Referring to Figure 7, the local shear stress on the horizontal section as a result of the finite
element analysis is as follows: a maximum value of 12.5 ksi near member L2-L3, and two
peak values of 9.5 ksi and 10.5 ksi within the gusset plate. The maximum value is
influenced by stress concentration at the interface between the plate and the truss member.
In comparison, an average shear stress of 6.6 ksi is calculated through Mathcad, which is
consistent with manual calculations. Based on simple beam theory, a maximum shear
stress of 1.5 times the average stress (9.8 ksi) is assumed to occur at the middle of a
section. This maximum value is approximately equal to the peak shear stresses calculated
through finite element analysis.
Design or Evaluation Checks
The second part of the Mathcad procedure consists of checking various design
requirements for gusset plates in the AREMA Manual of Railway Engineering, including
new requirements by AREMA Committee 15, for each of three critical sections (A-A, B-B,
and C-C). This part consists of the following steps:
1. Design checks consistent with draft Article 15-9.1.5.4.b:
Normal stresses on the Whitmore section
Compressive stress at plate edge
Tensile stress at plate edge
Average shear stress
Unsupported edge length requirement
Rivet or bolt shear capacity
Bolt slip-capacity
Bearing capacity
Block shear capacity
2. Allowable stresses per Table 15-1-11:
Shear on gross section (0.35Fy)
Tension on gross section (0.55Fy)
Compression on gross section (< 0.55Fy) based on buckling of unsupported
edge and buckling factor and average buckling length for Whitmore section
as per draft Article 15-9.1.5.4.b
Shear on rivet or bolt
Bearing on rivet or bolt
3. Allowable block shear per Article 15-1.5.9.e
4. Unsupported edge length to thickness ratio of less than or equal to 2.06 √E/Fy as
per draft Articles 15-7.3.4.1.c and 1.5.4.c
5. Slenderness ratio (ratio of length to least radius of gyration) of less than or equal to
100 per draft Article 15-9.1.5.4.b
A detailed presentation of an example with design checks is beyond the scope of this
paper.
CONCLUSIONS
Presented in this paper is a simple and effective procedure for performing two-dimensional
structural analysis of gusset plates in railroad truss bridges, through combined use of beam
elements for truss members and plate elements for gusset plate. A typical lower chord joint
is modeled and analyzed, and stress results are compared to the historic Whitmore testing.
Locations of peak values of principal stresses as determined by the analysis are consistent
with those reported by Whitmore. The same is true for the normal stress on a horizontal
section, whereby peak values of either tensile or compressive stresses are located within
the gusset plate, not at its edges as predicted by simple beam theory. Further, the
distribution section for truss member forces is consistent with the Whitmore section,
defined by two lines making 30 degrees with the axis of a member, starting at its outer
corner rivets and intersecting a third line drawn along its inner row of rivets. Versatility of
the finite element procedure is demonstrated by modeling and analyzing a non-typical
gusset plate at an upper chord joint.
A Mathcad work sheet is developed for analysis and evaluation of gusset plates. The
analysis part of the worksheet consists of calculating normal and shear stresses on
horizontal and vertical sections. For the typical lower chord joint, calculated stresses on a
horizontal section are compared with those from the finite element analysis. Maximum
normal stress values from Mathcad are 14% to 33% less than those from the finite element
analysis. An average shear stress from Mathcad is converted to maximum shear stress,
which is approximately equal to peak shear stresses from the finite element analysis. Listed
in the design and evaluation part of the Mathcad work sheet are various checks on gusset
plate design, as per the AREMA Manual of Railway Engineering, including draft
requirements by AREMA Committee 15.
REFERENCES
1. Whitmore, R.E., Experimental Investigation of Stresses in Gusset Plates, May 1952
2. FHWA Report H-08-1, Adequacy of the U10 & L11 Gusset Plate Designs for the
Minnesota Bridge 9340 (I-35W over the Mississippi River), January 2008
3. NYSDOT Technical Advisory 08-001, Truss Gusset Plate Analysis, May 2008
4. NCHRP 12-84 Guidelines for the Load and Resistance Factor Design and Rating of
Riveted, Bolted and Welded Gusset-Plate Connections for Steel Bridges, June 2008
– Present (In-progress Testing at the Federal Highway Administration (FHWA),
Turner-Fairbanks Highway Research Center (TFHRC))
5. FHWA, Finite Element Modeling of I-35W Bridge Collapse Final Report, TFHRC
Report, October 2008
6. FHWA-IF-09-014, Load Rating Guidance and Examples for Bolted and Riveted
Gusset Plates in Truss Bridges, February 2009
7. NCHRP, Guidelines for the Load and Resistance Factor Design and Rating of
Riveted, Bolted, and Welded Gusset-Plate Connections for Steel Bridges, Project
12-84, 2008-Present
8. Bentley Systems, Inc., STAAD.Pro Structural Software, Version V8i, 2010
9. AREMA, Manual of Railway Engineering, American Railway Engineering and
Maintenance-of-Way Association (AREMA), 2010
