Abstract
Steel and composite structures remain essential to modern infrastructure because of their high
efficiency, adaptability, and potential for enhanced durability. This Special Issue brings together six
contributions relevant to steel and composite structures, reflecting recent progress in understanding their
structural behaviour, improving design methods, and developing multifunctional structural systems.
The papers included in this issue cover a broad range of topics, including fatigue crack initiation in
steel arch bridge hangers, block shear behaviour of bolted stainless steel angle connections, corrosion
induced degradation of carbon and stainless steels, structural performance of Fe-Mn damping steel
composite slabs and beam-columns, and stiffness modelling of long-bolted steel joints. Together, these
studies address key challenges related to fatigue, durability, connection performance, corrosion resistance,
vibration control, acoustic performance, and design reliability.
A notable feature of this Special Issue is the combined use of experimental testing, numerical
simulation, analytical modelling, and design code assessment. Several papers propose improved design or
modelling approaches, while others provide new experimental evidence for emerging materials such as
stainless steel and Fe-Mn damping steel. These contributions demonstrate the continuing evolution of steel
and composite structures from conventional load-bearing systems toward more durable, resilient, and
multifunctional structural solutions.
We hoped that this Special Issue will provide a useful reference for researchers and practising
engineers working on the analysis, design, assessment, and maintenance of steel and composite structures.
Key Words
Address
Scientia Professor Brian Uy
The University of New South Wales, Australia
Dr. Yuchen Song
Imperial College London, United Kingdom
Dr. Youtian Wang
The Hong Kong Polytechnic University, Hong Kong SAR, PR China
Abstract
This fundamental study investigates possible causes of crack initiation observed at the ends of hangers in
a through-type steel arch bridge located in Nagasaki, Japan. Through analysis of long-term measurement data and
eigenvalue analysis, it was determined that the primary factor in crack initiation was not the vibration of the hangers
themselves but rather the wind-induced buffeting response of the entire bridge structure. The vibration modes
responsible for fatigue crack development were estimated using response spectrum analysis and forced displacement
analysis. Additionally, by examining the actual damage locations and structural responses, hangers that may be
susceptible to future fatigue damage were identified. This comprehensive approach provides valuable insights into
the mechanisms of hanger end crack initiation in through-type steel arch bridges and offers guidance for preventive
maintenance strategies by focusing on the critical vibration modes identified by global analysis.
Key Words
fatigue; steel arch bridge; vibration; wind-induced buffeting
Abstract
Stainless steel angle sections are widely used in building structures due to their structural simplicity,
efficiency in carrying axial forces, and excellent corrosion resistance. This study presents a comprehensive numerical
study on the block shear behaviour and design of bolted stainless steel angle connections. An advanced FE
simulation framework incorporating full-range constitutive model, fracture criterion, and material anisotropy was
developed and validated against existing experimental results. Parametric analyses were then conducted considering
different combinations of stainless steel grades (austenitic S304 and duplex S2205), bolt hole diameter, end and edge
distances, bolt gauge and pitch distances, plate thickness, and the number of bolt lines and rows. The results showed
that increasing the number of bolt rows, end distance, and pitch distance enhanced the ultimate tensile resistance by
enlarging the effective shear area, while more bolt lines, larger gauge and edge distances improved the resistance
through the increase of effective tensile area. In contrast, the outstanding leg width, bolt hole diameter and plate
thickness had a limited influence on the normalised ultimate resistance. A consistent block shear failure mechanism
was observed for all connections. Austenitic stainless steel specimens exhibited two failure modes, including tensile
necking with shear cracking and tensile necking with shear yielding, whereas duplex stainless steel specimens
showed only the tensile necking with shear yielding mode. Comparisons with existing international design standards
revealed notable discrepancies. Therefore, a modified design approach was proposed to improve the accuracy of
block shear resistance predictions for bolted stainless angle connections.
Key Words
block shear failure; bolted connections; design method; finite element modelling; stainless steel
angles
Address
Youtian Wang:1)Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University,
Hong Kong SAR, China
2)Department of Building and Real Estate, The Hong Kong Polytechnic University, Hong Kong SAR, China
Yuchen Song:Department of Civil and Environmental Engineering, Imperial College London, London, UK
Yifan Zhou:School of Civil Engineering, The University of Western Australia, Perth, Australia
Qun He:Department of Building and Real Estate, The Hong Kong Polytechnic University, Hong Kong SAR, China
Yicen Liu:Department of Building and Real Estate, The Hong Kong Polytechnic University, Hong Kong SAR, China
Abstract
This study systematically investigated the corrosion damage evolution and mechanical property
degradation mechanisms of Q345 steel, 316L austenitic stainless steel, and 2205 duplex stainless steel. A 2000-hour
copper-accelerated salt spray test was conducted. The results reveal distinct differences in corrosion morphology and
degradation mechanisms among the three steels. Q345 steel undergoes uniform corrosion, leading to a continuous
degradation pattern. In contrast, both stainless steels are characterized by localized pitting corrosion, with 2205
duplex stainless steel exhibiting the highest pitting resistance owing to its duplex microstructure and greater alloy
content. Mechanical tests demonstrate a decline in both strength and ductility with prolonged exposure. Q345 steel
suffers the most severe degradation in mechanical properties, while 2205 duplex stainless steel maintains the best
mechanical stability. Based on the experimental data, a corrosion damage variable is introduced into classical
constitutive models, leading to the development of a time-dependent dual-hardening model and a Ramberg-Osgood
model. Validation analysis indicates that the piecewise-function-based dual-hardening model characterizes the
mechanical response of corroded materials during both the hardening and necking stages more accurately than the
Ramberg-Osgood model, with an average prediction error only one-quarter of the latter. The established corrosion
constitutive relationship provides a critical theoretical and modeling basis for assessing the durability and performing
numerical simulations of steel structures in corrosive environments.
Key Words
constitutive model; material property degradation; salt spray corrosion; stainless steel
Address
Jia Wang:School of Transportation, Southeast University, Nanjing, Jiangsu, 211189, China
Haiyang Gu:School of Transportation, Southeast University, Nanjing, Jiangsu, 211189, China
Hongqi Wei:School of Energy and Environment, Southeast University, Nanjing, Jiangsu, 211189, China
Abstract
Fe-Mn damping steel exhibits excellent damping characteristics and mechanical properties, providing an
innovative material solution for vibration and noise reduction in modern building structures. This study
systematically investigates the flexural behaviour and acoustic performance of composite slabs incorporating closed
Fe-Mn damping steel profiled sheets through four-point bending tests on four damping steel specimens and one
Q355 conventional mild (CM) steel control specimen. Based on the experimental results, the typical failure modes
were revealed and the effects of rib height, rib pitch, and concrete thickness on the flexural behaviour were examined.
The test results were further compared with design methods in accordance with the current Chinese (JGJ 138-2016)
and European (EN 1994-1-1) standards, demonstrating that the design provisions are conservatively safe and can be
directly applied to the design of such damping steel composite slabs. In addition, acoustic measurements confirmed
the superior noise reduction performance of the damping steel compared with CM steel. This research provides
valuable reference for the engineering application of structural components that integrate load-bearing capacity with
vibration and noise reduction functions.
Address
Jiangwen Li:1)Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing,100083, China
2)Ansteel Beijing Research Institute Co., Ltd., Beijing 102200, China
Yejia Wang:Department of Civil Engineering, Tsinghua University, Beijing 100084, China
Shanglin Lv:Central Research Institute of Building and Construction Co., Ltd, MCC Group, Beijing 100088, China
Wei Liu:Shanghai Baoye Group Corp., Ltd, Shanghai 200941, China
Xuemin Wang:Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing,100083, China
Huiyong Ban:Department of Civil Engineering, Tsinghua University, Beijing 100084, China
Abstract
Steel joints play a crucial role in the overall behavior of structures. As a result, both researchers and
practitioners have made significant efforts to improve joint design and develop reliable calculation methods. One
widely adopted solution for assembling joints with hollow column sections is the use of long bolts, typically
consisting of threaded rods with nuts, this approach also enhances both stiffness and resistance. However, long bolts
have not been extensively studied in cases where the column is an open section, nor are there established
formulations for their structural analysis in such configurations. Therefore, this paper proposes a mechanical model to
calculate the stiffness of the tension zone of the column when the joint is assembled using long bolts. The mechanical
model is applicable to symmetrically loaded double-sided joints in which the column is an open H or I section,
connected using long bolts. It consists of three components: the column flange in bending, the column web in
tension, and the long bolts in tension. The proposed formulation is supported by an experimental campaign of six
specimens, as well as a parametric study using calibrated finite element models. The numerical models were
calibrated against experimental results, specifically force-displacement and force-deformation curves.
Key Words
bolted steel joints; component method; experimental tests; finite element model; long bolts
Address
Manuel Lopez:Structural Analysis Laboratory, CITENI, Ferrol Industrial Campus, University of A Coruña, Mendizabal s/n Campus de Esteiro 15403 Ferrol, Spain
Alfonso Loureiro:Structural Analysis Laboratory, CITENI, Ferrol Industrial Campus, University of A Coruña, Mendizabal s/n Campus de Esteiro 15403 Ferrol, Spain
Ruth M. Gutierrez:Structural Analysis Laboratory, CITENI, Ferrol Industrial Campus, University of A Coruña, Mendizabal s/n Campus de Esteiro 15403 Ferrol, Spain
Jose M. Reinosa:Structural Analysis Laboratory, CITENI, Ferrol Industrial Campus, University of A Coruña, Mendizabal s/n Campus de Esteiro 15403 Ferrol, Spain
Abstract
Fe–Mn damping steel is a promising structural material that exhibits excellent damping capacity, high
ductility, and stable strength characteristics, making it suitable for seismic and vibration-sensitive structures. This
study presents an integrated experimental and numerical investigation on welded I-section beam–columns made of
Fe–Mn damping steel under combined axial compression and minor-axis bending. A total of seven specimens,
including one Q235 carbon steel reference, were tested under eccentric axial loading, with measurements focusing on
initial global and local geometric imperfections as well as load–lateral deflection responses and failure modes.
Additionally, acoustic tests were conducted on both damping steel and Q235 specimens to quantify their noise
attenuation characteristics under mechanical excitation. The finite element models were calibrated using the results
from the present eccentric compression tests and a prior axial loading study. Following validation, the models were
used to conduct a parametric study covering a wide range of cross-sectional geometries, member slenderness levels,
and loading scenarios. The resulting numerical data were employed to assess the resistance predictions provided by
existing design standards, including EN 1993–1-1, ANSI/AISC 360-22, and GB 50017-2017. The comparison
indicated that EN 1993–1-1 yields generally acceptable yet scattered predictions, while the ANSI/AISC 360-22
method tends to produce non-conservative estimates with substantial variability when applied to damping steel
members. In comparison, GB 50017-2017 offers overall conservative results but with relatively high dispersion. To
improve predictive accuracy, a modified design framework was proposed by concurrently refining the buckling
curve and recalibrating the interaction factors. Reliability analysis conducted in accordance with EN 1990 confirmed
the effectiveness of the proposed method, with a derived partial safety factor of 1.140.
Key Words
beam-column; test; combined axial compression and minor-axis bending; damping steel; Finite
Element (FE); welded I-section
Address
Peng Dai:Department of Civil Engineering, Tsinghua University, Beijing, China
Yejia Wang:Department of Civil Engineering, Tsinghua University, Beijing, China
Jiangwen Li:Ansteel Beijing Research Institute Co., Ltd., Beijing, China
Shanglin Lv:Central Research Institute of Building and Construction Co., Ltd., MCC Group, Beijing, China
Li Ma:Central Research Institute of Building and Construction Co., Ltd., MCC Group, Beijing, China
Huiyong Ban:Department of Civil Engineering, Tsinghua University, Beijing, China
