Abstract
To study the crack propagation law of rib-to-diaphragm welds in orthotropic steel decks (OSDs) of steel
arch bridges, a fatigue crack propagation prediction model integrating structural health monitoring (SHM) data, linear
elastic fracture mechanics and Markov chain is developed with the Changyun Bridge as a case study. Firstly, time
frequency characteristics of long-term strain monitoring data of the steel box girder are analyzed. Wavelet analysis is
used to separate ambient temperature stress and filter out random environmental disturbances and measurement
noise. The stress spectrum under vehicle loads is counted by the rainflow method, and the Gaussian mixture
distribution is adopted to fit the fatigue stress range and calculate the daily effective stress range. The effective stress
at key positions is determined via the hot-spot stress equation. Based on linear elastic fracture mechanics, the state
transition probability matrix for crack propagation at the weak parts of rib-to-diaphragm joints is constructed.
Combined with the initial crack state probability distribution and Markov chain theory, the fatigue crack depth and
propagation curves of the structure throughout its service life are obtained. The results show that the proposed model
can accurately capture the correlation between consecutive states during crack propagation. It innovatively realizes
the coupled prediction driven by real-bridge monitoring data and probabilistic state evolution, and is more adaptable
to random traffic loads and multi-source interferences than traditional fracture mechanics models. It can effectively
predict the full-life fatigue state evolution of OSDs, providing a more accurate and practical new method for
evaluating the service performance of OSDs in steel box girders.
Key Words
crack depth; Gaussian mixture distribution; hot-spot stress; Markov chain model; monitoring
data analysis
Address
Yang Ding: 1)State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing
400074, China
2)Department of Civil Engineering, Hangzhou City University, Hangzhou 310015, China
3)Zhejiang Engineering Center of Road and Bridge Intelligent Operation and Maintenance Technology,
Zhejiang Scientific Research Institute of Transport, Hangzhou 310023, China
Ning-Yi Liang: 1)Zhejiang Engineering Center of Road and Bridge Intelligent Operation and Maintenance Technology,
Zhejiang Scientific Research Institute of Transport, Hangzhou 310023, China
2)School of Civil and Environmental Engineering, Changsha University of Science and Technology, Changsha 410114, China
Da Han: 1)Department of Civil Engineering, Hangzhou City University, Hangzhou 310015, China
2)Department of Civil Engineering, Zhejiang University, Hangzhou 310058, China
Xue-Song Zhang:State Key Laboratory of Mountain Bridge and Tunnel Engineering, Chongqing Jiaotong University, Chongqing
400074, China
Ping Wu:China Coal Mine Construction Group Co., Ltd., Hefei 230071, China
Hao Hu:Zhejiang Engineering Center of Road and Bridge Intelligent Operation and Maintenance Technology,
Zhejiang Scientific Research Institute of Transport, Hangzhou 310023, China
Xiao-Dong Sui:Department of Civil Engineering, Hangzhou City University, Hangzhou 310015, China
Abstract
The issues of stiffness mutation and whiplash effect in complex hybrid structural systems, such as adding
floors to existing buildings, can be effectively solved by the new outsourced joint. The research on the bearing
capacity calculation method and restoring force model of the new joint can facilitate its application in the added-story
and reconstruction project of the old residential areas. In this paper, a nonlinear finite element model for the new
outsourced joint was established with the ABAQUS software. Following validation of the model, the influence of
relevant parameters on the seismic performance of the new joint was investigated. Subsequently, the calculation
formulas for its bending and shear capacities were fitted, and a restoring force model incorporating structural
performance degradation was established. The results indicated the new joint had excellent energy dissipation
capacity, superior bearing capacity, and substantial plastic deformation ability. The bearing capacity calculation
formula proposed based on the parameters results, such as the axial compression ratio and building service time, had
good accuracy and could serve as a reliable basis for the subsequent in-depth research on the joint bearing capacity.
The proposed restoring force model, which incorporated structural performance degradation, accurately captured the
hysteresis behavior of the new joint under cyclic loading and could provide a basis for its full-process seismic
dynamic analysis.
Key Words
bearing capacity calculation methods; hybrid structural systems; new outsourced joint; restoring
force model; skeleton curves
Address
Xiuzhen Pan: School of Civil Engineering and Architecture, Xi'an University of Technology, Xi'an 710048, China
Qiang Wang: School of Civil Engineering and Architecture, Xi'an University of Technology, Xi'an 710048, China
Hongqi Wang:Shaanxi Jiangong (Yan'an) New Building Materials Co., LTD., Yan'an 717403, China
Hao Liu:Shaanxi Jiangong (Yan'an) New Building Materials Co., LTD., Yan'an 717403, China
Youwei Feng:New Era (Xi'an) Design Engineering Co., Ltd., Xi'an 710018, China
Qin Zhao:School of Civil Engineering and Architecture, Xi'an University of Technology, Xi'an 710048, China
Abstract
Fiber and metal materials are widely used as backing layers in composite armor. Metallic components are
particularly effective at preventing secondary injuries from fragment spallation, while fiber materials dissipate
significant kinetic energy through extensive deformation. The penetration process between the back plate and the
projectile is relatively complex, characterized by back plate deformation and delamination. In this study, a theoretical
model for composite armor subjected to projectile impact is established based on the collaborative deformation
mechanism between the fiber and metal layers to predict both the residual velocity of the projectile and the back-face
deformation (BFD) of the rear plate. The model is validated through comparison with experimental data. The failure
modes of both single-layer and double-layer ductile targets are analyzed, along with the effects of layer sequence and
areal density on the anti-penetration performance of composite armor. The results show that the failure modes of fiber
and metal-fiber targets vary with areal density, whereas fiber-metal targets exhibit consistent failure behavior regardless
of areal density. Among all configurations, the fiber-only target achieves the lowest areal density of 27.16 kg/m
Key Words
analytical model; back face deformation; ballistic limit; collaborative deformation; composite
armor; optimal design
Address
Mengting Tan:School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China
Xianfeng Zhang: School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China
Wei Xiong: School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China
Chuang Liu: School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China
Muhao Liu: School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P.R. China
Yangwei Wang: 1)School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, P.R. China
2)National Key Laboratory of Science and Technology on Materials Under Shock and Impact,
Beijing 100081, P.R. China
Abstract
Contemporary high-rise construction necessitates increasingly stringent seismic performance
requirements. Given that beam-column joints serve as critical load-bearing components, a comprehensive investigation
into their seismic performance is warranted. In high-rise structures, conventional steel beam-to-CFST column
connections are often prone to premature local flange buckling within negative moment regions. To address this
limitation, an innovative reinforced concrete beam-column connection is proposed, featuring beam-end reinforcement,
and utilizing steel-reinforced concrete beams in place of conventional steel beams. Angle steel limiters are incorporated
within the column joint region to constrain the horizontal deformation of stiffeners, prevent slippage of the stiffeners,
and enhance the joint's load-bearing capacity. Additionally, longitudinal stiffening plates are embedded within the
column to optimize panel zone stress distribution and improve beam-to-column load transfer efficiency. Three
prototype specimens are subjected to low-cycle reversed loading tests to evaluate failure modes, hysteretic behavior,
deformation characteristics, and energy dissipation capacity. Furthermore, the effects of the steel tube beam wall
thickness, the column's outer end plate thickness, and the number of stiffeners is analyzed using ABAQUS software.
Experimental results demonstrated that the proposed connection system exhibited superior seismic performance.
Concrete-filled rectangular steel tube beams increased the specimen's load capacity by 25% compared to conventional
steel beams. Additionally, an increase in the thickness of the column
Address
Haiyan Xu:College of Civil Engineering, University of Science and Technology Liaoning,
189 Qianshan Middle Road, Lishan District, Anshan, Liaoning 114051, P.R. China
Huaguo Gao:College of Civil Engineering, University of Science and Technology Liaoning,
189 Qianshan Middle Road, Lishan District, Anshan, Liaoning 114051, P.R. China
Yanguo Yue:Shanghai Baoye Group Corp., Ltd, 2457 Fuyuan Road, Baoshan District, Shanghai 201908, P.R. China
Junwei Yang:College of Civil Engineering, University of Science and Technology Liaoning,
189 Qianshan Middle Road, Lishan District, Anshan, Liaoning 114051, P.R. China
Lu Yang:College of Civil Engineering, Shenyang University of Technology, 111 Shenliao West Road,
Economic-Technological Development Zone, Shenyang, Liaoning 110870, P.R. China
Abstract
Continuous composite beams are widely used in modern transportation networks. However, under normal
service conditions, cracks would occur in the negative moment region due to the interface slip between the concrete
slab and steel beam, which undermines the structural durability. To address this issue, six three-span continuous
composite beams with varied longitudinal shear stiffness were first tested under concentrated load. The studied
variables included the number of bolts and the preload of bolts. The initial stiffness, strain distribution and interface slip
in the negative moment region were studied and the relationship between the horizontal shear force and interface slip
was obtained. In parallel to experiments, refined finite element models were established and the accuracy of the models
was verified by the test data. Research showed that reducing bolt preload from 80 to 0 kN decreased stiffness by
12.26%, while slip increased from 0.0069 to 0.0596 mm, and reducing bolts from 6 to 0 expanded the slip region by
51.21%. Based on the numerical results, the undetermined constant in the proposed response between horizontal shear
force and interface slip was obtained, while an analytical model to predict the interface slip in the negative moment
region of three-span continuous composite beams was proposed. The predictions agreed well with the test data, with
errors within 15%.
Key Words
continuous composite beam; finite element modeling; interface slip; longitudinal shear stiffness;
negative moment region; shear connection degree
Address
Wen Zeng: 1)School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China
2)Department of Civil and Natural Resources Engineering, University of Canterbury, Christchurch 8140, New Zealand
Liang Fan: School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China
Ke Jiang:Department of Civil and Natural Resources Engineering, University of Canterbury, Christchurch 8140, New Zealand
Ying Qin:School of Civil Engineering, Southeast University, Nanjing 211189, China
Guocao Shi:School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China
Qiang Wen:School of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China
Abstract
This study develops a finite element simulation framework to investigate the nonlinear thermomechanical
behavior of reinforced concrete beams (RCBs) strengthened with temperature-dependent functionally graded material
plates (TDFGMPs). The strengthening plates are assumed to be perfectly bonded to the tension face of the beam,
forming an integrated composite system. The numerical model, implemented in ANSYS, incorporates a range of
thermal loading scenarios to evaluate the effects of temperature on the structural response. The concrete is modeled
using a quasi-brittle material formulation to capture cracking and crushing behavior, while the TDFGMP is
characterized using a bilinear elastoplastic model. The temperature-sensitive mechanical properties of the FGM plate
are derived through a nonlinear gradation law in combination with the Tamura–Tomota–Ozawa (TTO) model,
enabling accurate representation of spatial and thermal heterogeneity. Validation against benchmark results from the
literature confirms the accuracy of the proposed modeling strategy. Parametric studies are conducted to assess the
influence of thermal gradients, material gradation profiles, plate thickness, and boundary conditions on structural
performance. The results demonstrate that incorporating temperature-dependent FGMs enhances the thermal
resistance and mechanical integrity of RCBs, highlighting the potential of TDFGMPs as an effective strengthening
solution for concrete structures exposed to elevated or varying thermal environments.
Key Words
Bilinear plasticity; Finite elements simulation; Functionally graded materials (FGMs); Nonlinear
analysis Reinforced Concrete Beams (RCBs); Temperature-Dependent Strengthening; thermomechanical
behavior; TTO model
Address
Alaa A. Abdelrahman: 1)Mechanical Design & Production Department, Faculty of Engineering,
Zagazig University, P.O. Box 44519, Zagazig, Egypt
2)Industrial Engineering Department, Jeddah International College (JIC), P.O. Box 23831, Jeddah, Saudi Arabia
Hanaa E. Abd-El-Mottaleb:Department of structural Engineering, Faculty of Engineering, Zgazig university, P.O. Box 44519, Zagazig, Egypt
Mohamed G. Elblassy:Department of structural Engineering, Faculty of Engineering, Zgazig university, P.O. Box 44519, Zagazig, Egypt
Eman A. Elshamy: 1)Department of structural Engineering, Faculty of Engineering, Zgazig university, P.O. Box 44519, Zagazig, Egypt
2)Dean of Al-Obour Higher Institute for Engineering and Technology, Kilo 21, Cairo–Belbeis Desert Road, P.O. Box 27, Obour City, Egypt
Abstract
Stainless steel plate-concrete composite structures have garnered extensive attention in nuclear power
engineering. Notably, the connection performance of stainless steel studs for these structures is of crucial significance.
However, research concerning the shear performance of stainless steel studs remains relatively limited. To address
this gap, four groups of S32101 (EN 1.4162) duplex stainless steel studs and two groups of ML15 studs of
conventional steel were designed for push-out tests. The arrangement and spacing of the studs were deliberately
diversified. Parametric analyses of push-out specimen models were performed via the finite element (FE) method,
and the FE results were validated against experimental data. The overarching objective was to investigate the effects
of stud diameter, spacing, and aspect ratio on the shear performance. The results showed that stainless steel studs
exhibited higher shear bearing capacity and better ductility than ML15 studs. The average shear bearing capacity of a
single stud in a single-row arrangement was 1.16 times that of the double-row arrangement. An increase in the stud
spacing from 150 mm to 200 mm resulted in an 18% enhancement in shear capacity and a 2.4% increase in ultimate
slip. However, when the spacing exceeded the code limit value, the shear bearing capacity of the specimens declined.
Based on the experimental and finite element results, a predictive model for the load-slip curves of S32101 stainless
steel studs was developed. Furthermore, the applicability of China
Address
Lili Wu: School of Mechanics and Civil Engineering, China University of Mining and Technology-Beijing, Ding No.11
Xueyuan Road, Haidian District, China
Haining Cui:School of Mechanics and Civil Engineering, China University of Mining and Technology-Beijing, Ding No.11
Xueyuan Road, Haidian District, China
Qianpeng Nie:School of Mechanics and Civil Engineering, China University of Mining and Technology-Beijing, Ding No.11 Xueyuan Road, Haidian District, China
Haipeng Wu:School of Mechanics and Civil Engineering, China University of Mining and Technology-Beijing, Ding No.11
Xueyuan Road, Haidian District, China
Yue Yu:China Nuclear Power Engineering Company Limited, No.117 Northwest Third Ring Road, Haidian District,
Beijing, China
Abstract
This study investigates innovative approaches to improve the shear strength of reinforced concrete (RC)
beams without shear stirrups. Testing was carried out on eleven specimens using a simply supported loading
configuration, consisting of two controls and nine strengthened members. Different strengthening configurations
were explored, with a focus on using anchored ferrocement strips (AFSs). In the ferrocement strips, strain-hardening
cementitious composites (SHCC) served as the high-strength mortar, while expanded steel mesh (ESM)
reinforcement was incorporated to boost strength and ductility. In addition, the study utilized a mechanical expansion
anchor (MEA) system that incorporated steel bolts, drop-in anchors, and perforated steel plates. The experimental
program arranged three beams per group, focusing on strip width (100, 75, 60 mm), anchorage conditions, and AFS
inclination (60°, 45°, 30°). The findings indicate that using AFSs significantly delays the onset of initial cracks and
reduces the separation between the original beam and the ferrocement layers. The inclined AFS technique, with
inclination angles of 30° to 60°, significantly enhances defective beams, increasing load-carrying capacity by 67% to
75%, elastic stiffness by 4% to 11%, and energy absorption by 335% to 376%. In addition, nonlinear 3D finite
element modeling was employed both to validate the experimental results and to conduct further parametric studies.
Key Words
3D model; anchored ferrocement strips; expanded steel mesh; externally bonded technique;
mechanical expansion anchor system
Address
Fathi A. Abdelmgeed:Civil Engineering Department, Faculty of Engineering, Kafrelsheikh University, Kafrelsheikh, Egypt
Abdullah Albogami:Department of Civil Engineering, Faculty of Engineering, Al-Baha University, Al-Baha 65779, Saudi Arabia
Jong Wan Hu:1)Department of Civil and Environmental Engineering, Incheon National University,
Incheon 22012, South Korea
2)Incheon Disaster Prevention Research Center, Incheon National University, Incheon 22012, South Korea
Saad A. Yehia:Civil Engineering Department, Higher Institute of Engineering and Technology, Kafrelsheikh, Egypt
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