This is only the Literature Review on residual stress.

1. A WRITE UP
ON
NUMERICAL ANALYSIS ON RESIDUAL STRESS ON PLATE
GIRDER
Submitted for partial fulfilment of the requirement for the award of the degree
of
MASTER OF TECHNOLOGY
In
STRUCTURAL ENGINEERING
By
Tejaskriya Pradhan
T19CE003
Under the guidance of
Dr. Debabrata Podder
DEPARTMENT OF CIVIL ENGINEERING
NATIONAL INSTITUTE OF TECHNOLOGY, MEGHALAYA
SHILLONG, MEGHALAYA – 793001

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INDEX
Sl Content Page
Front Page i
Index ii
Abstract iii
1 Introduction 1
2 Literature Review 3
3 Research Gap 15
4 References 16

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ABSTRACT
In steel construction, usually the production contains two stages: the manufacture of
parts under workshop conditions and the assembly on site. The former can be partially
automated and has a much higher level of reliability compared to site welds. This article
addresses the manufacture of such girders and proceeds to the production in the factory and
the simulation of the welding process. Main concerns are the prediction of imperfections of
plate girder with the aid of simulation tools and/or simplified engineering models. Their
impact on the component design is evaluated in a case study. Special focus is put on the
effect of residual welding stress. For this, different simplified distributions are compared with
results from welding simulation. The findings confirm the thesis that present
recommendations on the implementation of weld-induced imperfections must be rated
conservative.

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INTRODUCTION
1 General Introduction
Reasonable tolerances for steel plate out-of-flatness are required during fabrication
and construction of built-up structural members. For American highway bridges out-of-
flatness tolerances are currently set for some elements, but the engineering basis for these is
not clear (Herman 2001). This study determines the girder strength reduction associated with
out-of-flatness for I-shaped girder webs and flanges. Finite Element Analysis (FEA) is used
to construct flexural strength reduction curves for girders with various out-of-flatness
magnitudes, covering a range of girder cross-sections and spans. This study examines steel
girders rather than composite girders. Before setting of the concrete deck and formation of
composite action, the steel girder alone must support all the steel, concrete, and falsework
weight. This is a critical situation caused by compressive stresses resulting in local buckling
and instability. These compressive stresses exist in the upper flange at the middle of simply
supported span and in the lower flange at the interior pier of continuous I-shaped plate
girders. The effects of residual stresses on the mechanical performance are more significant
for welded sections and among which welded I shape is one of the most popular sections.
Recently a few studies were performed for such section members manufactured by 690 MPa
HSS.
Four different welded I sections with various sizes were examined by Rasmussen and
Hancock (1992, 1995), and three of them were made of shear cut plates with thickness of 6
mm and the other one was prepared from flame cut 8 mm plates. Two sections with the
thicknesses of 12 mm and 10 mm respectively were shear cut from welded I sections and
examined by Beg and Hladnik (1996). The corresponding magnitudes and distribution of
compressive residual stresses were given and further applied in the column buckling analysis,
however no measurements of residual tensile stresses near the weld region were reported.
types. Sectioning method was used to identify the longitudinal residual stress at different
locations including the weld regions. Through this study, the effects of the plate thickness and
width-thickness ratio, flange and web interaction, and weld process on the residual stress
distribution were identified. Based on the experimental results, a model to describe the
residual stress distribution and magnitudes was established for 460 MPa HSS welded I

5. 2 | P a g e
sections, and validated by the experimental measurements. In particular, the effects from
section dimensions can be clarified by the proposed model.
Fig :1 ( Heat Source Model propersoed by J. Goldak)
Source : “A New Finite Element Model for Welding Heat Sources,” by J. Goldak, A.
Chakravarti and M. Bibby.

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LITERATURE REVIEW
1. CL Tsai, SC Park, WT Cheng (1999)
With knowledge accumulated from previous studies in welding distortion control, the
objective of this paper is to address the basics of the warping mechanisms by studying the
thermal and mechanical behaviours of a thin aluminium panel structure using the finite
element method. The essential conditions for plate buckling to occur in the panel structures
were determined in this study. To study the effect of welding sequence on panel warping, a
method dubbed as the "joint rigidity method" (JRM) was developed to determine the
optimum welding sequence for minimum distortion. This paper demonstrates the principles
of the JRM method by showing a practical example.
This study demonstrated that during the welding assembly of a panel structure a skin
plate of normal thickness (e.g., >1.6 mm) can only buckle when the panel bends globally to
cause a large curvature in the skin plate. The structural weight and bending of the stiffeners
result in the global panel bending. Weld shrinkage in the T joints causes angular distortion in
the skin plate. Locating welds closer to the neutral axes of the panel cross sections can
control the global bending and minimize welding distortion of a stiffened panel. Other
mitigation methods include using heavier stiffeners to increase the moment of inertia of the
cross section or the eggcrate fabrication method to drastically improve the bending resistance
of the panel structure. Using the optimum welding sequence can improve the flatness of the
panel and minimize angular distortion in the skin plate. The joint rigidity method is effective
in determining the optimum welding sequence for minimum angular distortion in the skin
plate of stiffened panel structures.
2. Xiaohua Cheng, John W. Fisher (2003)
High tensile weld residual stress is one important factor contributing to fatigue crack
development even under reversal or compressive cyclic loadings. A compressive stress
induced by post-weld treatment is beneficial by eliminating the tensile residual stresses and
generating compressive residual stresses, which improves fatigue strength of welded
structures. A study is underway to characterize the magnitude and subsurface distribution of
residual stresses produced by post-weld treatments, particularly by Ultrasonic Impact
Treatment (UIT), and to establish the post-weld treatment effect on fatigue resistance. Two
post-weld treatments, UIT and shot peening, are involved in the present study.

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3. Igor Solodov, Juxing Bai, and Gerd Busse (2013)
Author used a resonant ultrasonic wave-defect interaction. RUSOD is shown to be
defect- and frequency selective imaging technique capable of distinguishing between
different defects by variation of ultrasonic frequency. A circular FBH (radius 1 cm, depth 2
mm) in PMMA (3mm) plate and A piezoelectric transducer is used as a material for testing.
On the basis of his test he founds the vibration pattern and LDR frequency.
4. A H Yaghi*,T H Hyde, A A Becker and W Sun (2008)
The finite element (FE) method has been applied to simulate residual axial and hoop
stresses generated in the weld region and heat-affected zone of an axisymmetric 50-bead
circumferentially butt-welded P91 steel pipe, with an outer diameter of 145mm and wall
thickness of 50mm. The FE simulation consists of a thermal analysis and a sequentially
coupled structural analysis. Solid-state phase transformation (SSPT), which is characteristic
of P91 steel during welding thermal cycles, has been modelled in the FE analysis by allowing
for volumetric changes in steel and associated changes in yield stress due to austenitic and
martensitic transformations. Phase transformation plasticity has also been taken into account.
The effects of post-weld heat treatment (PWHT) have been investigated, including those of
heat treatment holding time. Residual axial and hoop stresses have been depicted through the
pipe wall thickness as well as along the outer surface of the pipe. The results indicate the
importance of including SSPT in the simulation of residual stresses during the welding of P91
steel as well as the significance of PWHT on stress relaxation. Residual stresses have been
numerically determined in an axisymmetric single-U multi-pass butt weld of a P91 steel pipe,
taking the temperature dependences of the material properties into consideration as well as
allowing for the SSPT. The PWHT has also been numerically modelled, showing how
changes in PWHT holding time and material creep constants can affect the residual stress
profiles. The residual maximum principal stress, reflecting the superimposed tensile axial and
hoop stresses, is tensile and substantial on the outside surface of the welded pipe and in its
vicinity. When the SSPT is taken into account, the residual maximum principal stress
moderately reduces in magnitude on the pipe outer surface at the HAZ and approximately
half of the weld region; in the other half of the weld, in the vicinity of the last weld bead, the
residual stresses become moderately compressive.

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5. Shengming Zhang (2009)
The aim of this study was to investigate the effect of the welding-induced residual
stress on the ultimate compressive strength of plates and stiffened panels with a fixed
amplitude of geometric distortion, using nonlinear finite element analysis. The magnitude of
residual stress has been varied, so as to investigate its effect. Same shape of the geometric
distortions has been considered.
The ultimate compressive strength of plate and stiffened panel decreases due to the
presence of welding-induced geometric distortions and residual stresses. For plates with
slenderness ratio (β) 1.5 and 1.79, the ultimate strength decreased up to 11–13% due to the
applied compressive residual stress only. Similarly, the ultimate strength value for the
stiffened panel decreased up to 10–13% for the maximum applied compressive residual stress
for the chosen cases. The percentage decrease in the ultimate strength is dependent on the
amount of residual stress applied and the plate slenderness ratio. For example, when the
applied compressive residual stress is 5%, the maximum decrease in ultimate strength is 3.5%
for plates and 2.7% for the stiffened panels. Whereas, when 25% compressive residual stress
is applied the maximum decrease in ultimate strength is 11.2% for plates and 12.9% for the
stiffened panels.
This study was carried out on a limited number of structural models and a few levels
of residual stresses. More studies would be beneficial on a range of structural parameters and
various levels of residual stress levels to obtain inclusive conclusions
6. Omar Suliman Zaroog, Aidy Ali, B.B. Sahari, Rizal Zahari (2010)
Author used a aluminium alloy AA 2024-T351. The material was solution heat-
treated at 435°C and naturally aged to a substantially stable condition. The material was
received as a plate with a thickness of 6 mm, tensile strength of 484 MPa, yield strength of
348 MPa and an elongation of 15%.
On the basis of his test he founds the residual stress relaxation, number of cycles,
microhardness reduction, Relationship between cold work and microhardness. This research
demonstrates that the stability of residual stresses induced by different shotpeening intensities
in 2024-T 351 aluminium alloy due to cyclic loading.

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7. Rabih Kassab, Henri Champliaud (2010)
The analysis takes into consideration the temperature dependent non-linear material
properties and uses a new method introduced to compute the temperature dependent radiation
and convection combined coefficient of heat dissipation. Improvements in the calculation are
achieved by combining two types of meshing and using a relationship between the time
increment and the size of the elements. Time step is calculated as a function of the torch
position which is determined according to the finite element meshing. The FE simulation is
divided into two consecutive parts: the thermal simulation and the structural simulation.
The nodal temperatures got from the thermal simulation are applied to the nodes in the
structural simulation as thermal loads for each step of calculations. At the final step, all the
temperatures are set to the initial temperature Tf, i.e. the all assembly is brought back to the
ambient temperature.
The results of the numerical simulation are consistent and an in depth comparison
with data from a real experiment with instrumented plates (thermocouples and strain gages)
will be done in the next step.
An important advantage of FE modeling is its ability to follow the behavior of an
assembly during the welding process at any time and any location. The FE results show that a
sequential thermal and structural analysis is a powerful tool that can be used for studying in
depth the behavior of such an assembly.
8. Igor Solodov,Juxing Bai, Sumbat Bekgulyan, and Gerd Busse (2011)
In this, experimentally shows that to provide maximum acoustic wave-defect
interaction, the concept of a local defect resonance should be applied. The strong wave-defect
interaction is confirmed by resonance induced rise of local temperature of the defect in the
frequency band of its local resonance A model of resonant defect is used for the selection of
the wave frequency to enhance the excitation of the defect in nonlinear acoustics and
ultrasonic thermography. He used an oval horizontal delamination (25 x18 mm) formed due
to debonding of adjacent plies at 1mm depth in a 12-ply glass fibre reinforced composite
plate (200 x 25 x2.6 mm). A piezoelectric transducer embedded in the plate was used for a
wide-band (400 Hz–40 kHz) excitation of flexural waves. On the basis of his test he founds

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Vibration patterns at the fundamental defect resonance. This research demonstrates that the
concept of local mechanical resonance is applicable to the defects in solid materials.
9. Yashar Javadi, Mehdi Akhlaghi , Mehdi Ahmadi Najafabadi (2012)
Author used a 3D thermo-mechanical finite element analysis to evaluate welding
residual stresses in austenitic stainless steel plates of AISI 304L. The finite element model
has been verified by the hole drilling method. The validated finite element (FE) model is then
compared with the ultrasonic stress measurement based on acoustoelasticity. His experiments
involves a Austenitic stainless steel plate (A240-TP304L). Single pass butt-weld joint
geometry with a back-weld pass and without root gap is used. Two 600 x250 x 10 mm
normalized and rolled plates are welded in V-groove (90 degree included angle). On the
basis of his test he founds determine of penetration length.
This research demonstrates that the combination of finite element welding simulation
and ultrasonic stress measurement by LCR waves which can evaluate the welding residual
stress through the thickness of investigated stainless steel plate.
10. Huiyong Ban , Gang Shi (2013)
An experimental investigation was conducted in this paper to quantify the residual
stresses in 460 MPa steel welded I sections using sectioning method. The magnitude and
distribution of both compressive and tensile residual stresses were obtained based on 1972
sets of original data measured from eight different sections. The effects of width-thickness
ratios of the flange and web, steel plate thickness, weld type and interaction of the flange and
web were investigated. It was found that the compressive residual stress magnitude was
largely related to the sectional dimension, while no direct correlation was found with the
weld type and size for tensile ones.
It was found that the distribution of residual stress over the entire welded HSS I
sections was similar to that of NSS I sections. However the magnitudes exhibited different
values. In generally, a lower ratio between the residual stress magnitude and yield strength
was identified for HSS than that of NSS. This also implies that the residual stress effects
would be less severe on the structure responses especially the buckling behavior for HSS than
those for NSS. A modeling approach was established to describe the residual stress
distribution and magnitude over the entire I section. Major geometric effects of width-

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thickness ratio and thickness on compressive residual stresses were described and compared
well with those identified from experiments. This model is suggested to be applicable to the
460 MPa HSS flame cut welded I sections with the geometric range.
11. H. Pasternak, B. Launert ( 2015).
In steel construction, usually the production contains two stages: the manufacture of
parts under workshop conditions and the assembly on site. The former can be partially
automated and has a much higher level of reliability compared to site welds. This article
addresses the manufacture of such girders and proceeds to the production in the factory and
the simulation of the welding process. Results in terms of residual stress and distortion are
given and compared with typical engineering models. The validation of models is based on
experimental data obtained during and after the manufacture. For a subsequent capacity
analysis results are idealized and then implemented as initial conditions. The comparison of
different models allows a review of recent standards.
The combination of welding simulation and capacity simulation tools holds large
potential. However, as the application is still limited to small components, a contemporary
introduction to the construction area seems unlikely. For structural engineering, the use of
engineering models is adequate. Yet, no sufficient models are available as has been shown by
the comparison of welding simulation and simplified models. The recent classification, being
independent of the material and the manufacturing conditions, implies uneconomic design.
12. Bai-Qiao Chen, C. Guedes Soares (2016)
Welding methods that involve the melting of metal at the site of the joint are prone to
shrinkage as the heated metal cools. Residual stresses and distortion are then introduced by
the shrinkage. Welding distortion has negative effects on the accuracy of assembly, external
appearance, and various strengths of the welded structures. Non-uniform heat distributions,
plastic deformations and phase transformations occur on the material being welded. These
changes generate different residual stresses patterns for weld region and in the heat affected
zone (HAZ) .The residual stress may result in failure mechanisms such as fatigue, brittle
fracture, stress corrosion cracking, and creep cracking. Gannon investigated the effect of
welding-induced residual stress and distortion on ship hull girder ultimate strength and
revealed that the residual stresses reduced the ultimate strength of the stiffened plate by 11%
with a consequent reduction in hull girder ultimate moment of 3.3%. Therefore, it is of great

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significance to accurately predict the thermal and structural responses of the welding
operations, and to evaluate the strength capacity of the welded structures. Three-dimensional
thermo-elasto-plastic finite element analyses have been performed to predict the residual
stress distribution and distortion field in weld plates of an experimental scale. In the
sequential fillet welding, the peak temperature in the second weld is higher than the first one
because of the preheat effect.
The welding sequence results in an asymmetric deformed pattern in plates with small
stiffeners. However, the influence reduces when the height of stiffener increases. In the
ranges of 1.6e3.8 plate slenderness the displacement reduces when the thickness of the plate
increases, whereas in the cases of higher plate slenderness the trends are opposite.
The presence of the residual stress results in 5e7% reductions in longitudinal ultimate
strength of plates. The strength of the stiffened plate reduces with a quasi-linear behaviour
when the plate slenderness increases, and it reduces as the column slenderness increases.
13. Hartmut Pasternak, Benjamin Launert, Thomas Kannengie, Michael Rhode (2017)
This article provides an impression on potentials in applying nowadays welding
simulation tools in construction design. This is carried out exemplary on plate girders from
two structural steel grades. The calculated residual stresses are compared with measurements
by sectioning method. It has been repeatedly stated that present Eurocode models fail to
approximate the residual stresses. Especially for high strength steel (HSS) only limited
information is available on realistic occurring residual stresses in typical I-girders. The
investigations are aimed to give further guidance on these values.
A basic study on a welded I-girder from two structural steel grades was presented.
Experimental (and numerical) results have shown the decreased importance of longitudinal
residual welding stresses for S690. Absolute residual stress values were found to be on a
similar level as for S355. This underlines the necessity to adjust on the recent buckling
classification as given in Eurocode 3. It was also shown that numerical calculations are able
to reproduce the residual stresses. However, the effort is still not in a practically applicable
range. For that, simplified models are still in need. For a reliable statement on the residual
stresses, it is necessary to define the validity range which is missing for present Eurocode
models. For an advanced assessment of residual stresses some more recent (plasticity based)
theories were discussed. For an implementation in the civil engineering sector further
investigations are however necessary. Nevertheless, those models seem suitable for a
subsequent calculation of load-carrying capacity. Thus, the study provides a first valuable

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step on future studies in the structural level as well as for the development of a simplified
model.
14. Mahdi Asadnia, W. M. Kim Roddis (2018)
The nodes of the imperfection free steel plate girder are displaced into the buckled
shape and this distorted geometry is then used for non-linear analysis. Yield stress at the
welded intersection of flange and web is the basis for residual stress distributions, generated
using Heat Analysis in ANSYS to obtain temperature distributions. Lateral bracing is used to
prevent global lateral torsional buckling so local buckling controls the flexural moment at
onset of yielding. This approach allows a study of the effect of different magnitudes of
geometrical imperfection for a set of girder cross-sections for I-shaped plate girders. The
flexural moment at onset of yielding for various scales of the buckled shape are normalized
by the imperfection free steel plate girder moment, giving a measure of the effect of the size
of out-of-flatness on the performance of the girder. The results of FEA show dependency of
first yield moment to web slenderness ratios and out-of-flatness in I-shaped plate girders.
There is the critical web slenderness ratio of 124 for unstiffened I-shaped girders
which causes the most strength reduction for positive moments and drastic strength reduction
for larger slenderness for negative moment. No reverse behavior or critical web slenderness
was observed in stiffened I-shaped girders for 1D, 2D, and 3D transverse stiffener spacings.
The out-of-flatness tolerance was relaxed when it was strength wise possible. The proposed
strength-based web out-of-flatness criteria are provided for I-shaped plate girders. Adopting
total body first buckling mode shape as out-of-flatness pattern resulted in more conservative
web tolerance than Zhang’s proposed web tolerance for unstiffened I-shaped girders at
positive moments.
15. A. Vairis, R. Nikiforov (2014)
The effect of thermal-strain cycle on residual strains in thin-walled circular seams of
cylindrical shells using TIG butt welds was studied. Estimates were calculated using
numerical modelling. The structure was made of corrosion-resistant austenitic steels.

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A thermal deformation model has been applied to a real case to predict the residual
strain of thin-walled welded structures and shells with tight tolerances in order to identify
changes in geometric dimensions and optimize the structure by choosing the most efficient
arrangement for fixing the welded assembly, its build, the size of the expanding force
concentric sectors and the axial preload of the welded assembly at the preparatory stage for
welding. Modeling residual strains of the impact of the thermal-welding cycle during TIG-
welding of outer casing for a gas turbine engine showed that the magnitude of both the radial
and transverse shrinkage of welds thin shells does not depend on heat input when welding in
the range 111 - 156 kJ / m. A significant impact on the welded assembly transverse shrinkage
is exerted by a force in the axial direction in the machine for welding, which increases from
6.4 to 12.8 kN as the welded assembly transverse shrinkage changes from 0,247 to 0,476 mm
respectively.
16. Liam Gannon, Yi Liu, Neil Pegg, & Malcolm J. Smith(2012)
Nonlinear finite element analysis is used to simulate welding of stiffened plates,
giving the three-dimensional distribution of welding-induced residual stress and distortion.
Load-shortening curves are generated for the welded stiffened plates under axial
compression. These curves are then used as input in a hull girder ultimate strength analysis
using Smith's method. Results are compared with those of an ultimate strength analysis using
load-shortening curves derived from the IACS Common Structural Rules and with published
experimental data. The ultimate strength predicted using IACS curves was significantly
higher than the experimental result, whereas that determined using load-shortening curves
from finite element analysis agreed well with the measured value.
The stiffened plate failure modes considered are elasto-plastic failure, beam column
buckling, torsional buckling of stiffeners, and web local buckling of either stiffeners with
flanged profiles, or flat-bar stiffeners. Once again, for each increment in axial strain, the
lowest average axial stress calculated among the four failure modes is taken as the associated
stress in the load-shortening curve. The beam column buckling mode is considered in much
the same way as Gordo and Guedes Soares [5], with a slightly different plate effective width.
The stiffener torsional buckling calculation uses the Euler torsional buckling stress, corrected
by the Johnson-Ostenfeld formulation to account for inelastic effects. The calculation
considers the stiffness of the web to plate connection, and the reduction in plating effective
width as axial compressive strain increases. The web buckling failure mode accounts for the

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reduction in effective width of both the plate and the web due to axial compression, using
Faulkner's effective width formulation.
17. R. Thiébaud1 , J.-P. Lebet (2012)
Residual stresses must be taken into account when evaluating the stability of a steel
bridge girder. Residual stresses are unavoidable, as manufacturing processes for steel plates
introduce thermal residual stresses in the material. For welded built-up sections, such as those
commonly used in large steel plate girders, these thermal residual stresses are due to
1) cooling after rolling
2) flame cutting of the flanges
3) welding between the web and the flange.
Residual stresses can influence the lateral torsion buckling resistance of structural
steel members and need to be considered in design. This paper experimentally investigates
residual stresses due to flame cutting using the sectioning method. In this study, residual
stresses are measured after flame cutting and welding 60 mm thick steel (S355N) flanges, a
typical size used in the fabrication of bridge girders. Results from flame cutting confirm the
findings of previous studies which reveal that residual stress distributions have a high tensile
component at the flame cut edge. Procedures and testing of welding residual stresses are
presented without results. Residual stress measurements from this study could be used to
develop a longitudinal and through-thickness residual stress model for thick flame-cut plates
and welded plates used in bridge I-girder construction. Such a model could serve as an initial
state in non-linear finite element analyses to predict the residual stress influence on the LTB
of steel bridge girders.
18. Nauman Khurram, Eiichi Sasaki, Hiroshi Katsuchi & Hitoshi Yamada (2014)
Five plate girder ends simulated with different uniform and non-uniform types of
corrosion damage, at the base of the bearing stiffener are used in the experimental program.
The experimental results are modeled and verified on a Finite Element (FE) software
ABAQUS, considering shell-solid coupling elements formulation. The study is further
extended to various damage cases i.e., stiffener damage, stiffer plus web damages etc.
considering different damage heights and residual thicknesses. The study concludes that
minimum thickness within any damage height may be used to simulate the corrosion damage

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in a FE analysis. At the end, some empirical relationships are also proposed to estimate the
bearing strength of the plate girder affected by the local corrosion damage at plate girder end.
Bearing stiffener plays an important role in resisting the compressive load even for
the complete loss of the web in a locally small damage. Local plastic constraint effect is more
dominant in the uniform types of the damage and for small damage heights and this effect is
much lesser in non-uniform types of the damage and even vanishes for the large damage
heights. A relatively large bearing stiffener damage of 60 mm shift the local buckling within
the damage region and also reduce the capacity significantly. The ultimate strength reduces
drastically if web damage is combined with the stiffener damage and it also shifts the failure
mode from buckling to the crippling. A simple Rectangular Shaped corrosion damage with
Minimum Residual Thickness can be utilized in finite element simulation to evaluate the
bearing capacity of plate girder ends
19. Dong Ho Bae, Chul Han Kim, Seon Young Cho, Jung Kyun Hong & Chon Liang
Tsai (2014)
Numerical prediction of welding-induced residual stresses using the finite element
method has been a common practice in the development or refinement of welded product
designs. Various researchers have studied several thermal models associated with the welding
process. Among these thermal models, ramp heat input and double-ellipsoid moving source
have been investigated. These heat-source models predict the temperature fields and history
with or without accuracy. However, these models can predict the thermal characteristics of
the welding process that influence the formation of the inherent plastic strains, which
ultimately determines the final state of residual stresses in the weldment. The magnitude and
distribution of residual stresses are compared. Although the two models predict similar
magnitude of the longitudinal stress, the double-ellipsoid moving source model predicts
wider tensile stress zones than the other one.
This paper studied two most commonly used heat source models in the finite element
analysis of welding-induced residual stresses. The double-ellipsoid moving heat source
model is often referred in the studies and the ramping heat source model is often used for
analysis of thick section plate structures. Both models can predict characteristic temperature
solutions for estimating residual stresses. Both models would also require calibrations to
obtain accurate temperature results, but they can estimate reasonably accurate residual
stresses without any temperature adjustments. This implies that the total cumulative
shrinkage plastic strains at completion of welding could be calculated without using a

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detailed heat source model. This is due to the insensitivity of materials to high temperature
details. The complex physical material behaviours at high temperature are after all become
insignificant in contributing to the final formation of residual stresses.
20. Zhuqing Wang, Erik Denlinger, Panagiotis Michaleris & Alexandru D. Stoica (2016)
The rapid solidification and subsequent thermal cycles that material is subjected to
during additive manufacturing (AM) of a component result in a build-up of residual stresses,
which lead to part distortion, and negatively im-pact the component's mechanical properties.
We present a method for using neutron diffraction to validate thermomechanical models
developed to predict the residual stresses in Inconel 625 walls fabricated by laser-based
directed energy deposition. Residual stress calculations from neutron diffraction
measurements depend strongly on the determination of stress-free lattice spacings. After
measurement of stressed lattice spacing In conel 625 walls, reference samples were obtained
by extracting thin slices from the walls and cutting comb-type slits into these slices.
Reference lattice spacing were measured in these slices, as well as equivalent slices that were
also subjected to stress-relieving heat treatment. These heat treatments changed the reference
lattice spacing, and therefore affected residual strain measurements.
They present a method for using neutron diffraction to measure and compute residual
stresses in additively manufactured components, using an appropriate reference specimen
fordhkl0measurements. This experimental method can be used to validate, or can be
augmented by, thermo mechanical models, which predict continuum level residue-al stresses
within additively manufactured components. Therefore, neutron diffraction and modelling are
complementary techniques in determining residual stresses and strains in AM builds.
Extracting thin slices from builds, and mechanically stress relieving these samples through
the addition of comb-type cuts into the slicesis an appropriate way to relieve residual stress
and measure referencedhkl0values in neutron diffraction. While heat treatments may be used
to relieve residual stresses, they modify the microstructure of the material, potentially
changing the strain-free lattice spacing, and polluting neutron diffraction measurements of
lattice strain. In the present work, it is postulated that the heat treatment applied led to the
precipitation of carbides in the reference sample, reducing the measured strain-free lattice
spacing, which led to errors in the computation of residual stress and strain using neutron
diffraction

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RESEARCH GAP
After going through all journals, no sufficient models are available as has been shown
by the comparison of welding simulation and simplified models. Where for design purpose it
is very much necessary to know the residual stress and its effect. So we have to proceed
forther for perfect and economic model design and analysis.

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REFERENCES
1. H. Pasternak, B. Launert , T. Kraus(2015) "Welding of girders with thick plates
Fabrication, measurement and simulation"
2. Bai-Qiao Chen, C. Guedes Soares*,"Effects of plate configurations on the weld induced
deformations and strength of fillet-welded plates".
3. Rabih Kassab, Henri Champliaud "Finite element modeling of a welded t joint".
4. J. Goldak, A. Chakravarti and M. Bibby. “A New Finite Element Model for Welding Heat
Sources,”
5. J. Goldak, M. Bibby, J. Moore, R. House and B. Patel. “Computer Modeling of Heat Flow
in Welds,” Metallurgical Transactions B, vol. 17, no 3, 1986, p. 587-600.
6. Benjamin Launert*,a, Hartmut Pasternaka "Weld residual stresses effects in the design of
welded plate girders Simulation and Implementation."
7. Launert B., Rhode M., Pasternak H., Kannengiesser T., “Welding residual stresses in high-
strength steel & Experimental results”.
8. Mahdi Asadnia, W. M. Kim Roddis" Modeling Out-of-Flatness and Residual Stresses in
Steel Plate Girders".
9. A H Yaghi et al. ,"Finite element simulation of welding and residual stresses in a P91 steel
pipe incorporating solid-state phase transformation and post-weld heat treatment".
10. Yaghi, A. H. and Becker, A. A. State of the art review – weld simulation using finite
element methods, 2005 (NAFEMS, Glasgow).
11. Hartmut Pasternaka et al."Advanced residual stress assessment of plate girders through
welding simulation".
12. Huiyong Ban et al."Residual Stress of 460 MPa High Strength Steel Welded I Section:
Experimental Investigation and Modeling".
13. Alpsten, G. A. and Tall, L. (1970). “Residual stresses in heavy welded shapes.” Welding
Journal, 49(3), pp. 93-s-105-s.
14. Alpsten, G. A. and Tall, L. (1970). “Residual stresses in heavy welded shapes.” Welding
Journal, 49(3), pp. 93-s-105-s.
15. R.M. Sanderson a, Y.C. Shen b (2010),” Measurement of residual stress using laser-
generated ultrasound.”

20. 17 | P a g e
16. Dong Ho Bae et al. “Numerical Analysis of Welding Residual Stress Using Heat Source
Models for the Multi-Pass Weldment.”
17. Benjamin Launer, Hartmut Pasternaka "Weld residual stresses effects in the design of
welded plate girders Simulation and Implementation."
18. Nauman Khurram et al, “Finite element investigation of shear capacity of locally
corroded end panel of steel plate girder”.
19. R. Thiébaud et al. “Experimental study of residual stresses in thick steel plates ".
20. Zhuqing Wang et al." Residual stress mapping in Inconel 625 fabricated through additive
manufacturing: Method for neutron diffraction measurements to validate thermo mechanical
model predictions ".