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Rapid prediction model for fatigue life of composite laminates

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engineering Failure Analysis 2025年 178卷

作者： Sun, Jiaxing Pan, Wenfeng Sun, Lingyu Wang, Rihan Shi, Bingyan School of Transportation Science and Engineering Beihang University Haidian District 37 Xueyuan Road Beijing100191 China Beijing Key Laboratory for High-efficient Power Transmission and System Control of New Energy Beijing100191 China Beijing Hangshu Vehicle Data Research Institute Co. LTD. Beijing100062 China

Composite laminates provide exceptional design flexibility to meet diverse structural fatigue performance requirements through tailored combinations of fiber orientations and lay-up sequences. However, numerical simulations during the conceptual design phase require S-N curves corresponding to different design schemes as input to predict structural fatigue life. Experimentally deriving S-N curves for all possible designs is both time-consuming and costly. This study developed two analytical models or empirical formulas for engineering prediction solely based on the S-N curves of 0° and 90° unidirectional laminates (UDLs) to rapidly obtain that of arbitrary laminates. One model corresponds to UDLs with arbitrary fiber orientations, while the other corresponds to multidirectional laminates (MDLs) with arbitrary lay-up sequences. The weighting coefficient function for UDLs is derived from intralayer failure mechanisms, whereas for MDLs, it incorporates both intralayer and interlayer failure contributions. The analytical model is validated using experimental data from UDLs/MDLs GFRP laminates, with the R2 exceeding 0.7940, and an efficiency enhancement of 48 %. Finally, an application example is provided to illustrate the use of the analytical model for estimating the fatigue life of composite structures. © 2025

关键词： Laminated composites

A Method for Identifying the Damage Thresholds of Porcine Brain Under Low- and Medium-Strain Rates

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SSRN 2025年

作者： Qu, Zhihui Fu, Yimou Yang, Qiuping Wang, Jingyu Tang, Liqun Qu, Shaoxing State Key Laboratory of Fluid Power & Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Center for X-Mechanics Department of Engineering Mechanics Zhejiang University Hangzhou310027 China School of Civil Engineering and Transportation South China University of Technology No.381 Wushan Road Guangdong Guangzhou China

Predicting the damage thresholds of brain tissue is crucial for preventing permanent pathological changes and developing therapeutic interventions. This study presents a method for determining the damage thresholds of porcine brain tissue using experimental data and theoretical modeling. By conducting loading and unloading experiments on porcine brain samples, the mechanical responses under varying strain rates and loading conditions are analyzed. A constitutive model incorporating viscoelastic behavior, the Mullins effect and residual deformation is proposed, effectively characterizing the mechanical properties of the brain tissue. By calculating the ratio of damage-induced dissipated energy and viscoelastic dissipated energy, the extent of damage under different maximum compression strain is quantified. The method’s reliability is validated by comparing stress-strain curves from first-time and second-time loading. At a strain rate of 0.3 s⁻¹, the mild damage strain threshold is estimated to be 0.2–0.3, while the moderate-to-severe damage threshold falls within 0.3–0.4, aligning closely with values reported in the literature. Additionally, the damage strain thresholds at 200 s⁻¹ are consistent with those at 0.3 s⁻¹. The corresponding stress threshold at 200 s⁻¹ ranges from 5.9 to 11.4 kPa for mild damage and from 11.4 to 22.8 kPa for moderate-to-severe damage. The findings of this study are expected to contribute to brain damage prediction. © 2025, The Authors. All rights reserved.

关键词： Stress-strain curves

Increasing the Accuracy of Classification Models with a Scaler for Bus Rapid Transit (BRT) Reliability Values

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Increasing the Accuracy of Classification Models with a Scal...

International Conference on Electrical engineering and Computer Science (ICECOS)

作者： Muhammad Iman Nur Hakim Joko Siswanto Anas Azhimi Qalban Aninditya Anggari Nuryono Automotive Engineering Technology Politeknik Keselamatan Transportasi Jalan Tegal Indonesia Road Transportation System Engineering Politeknik Keselamatan Transportasi Jalan Tegal Indonesia Informatics Faculty of Dakwah Universitas Islam Negeri Profesor Kiai Haji Saifuddin Zuhri Banyumas Indonesia Department of Informatics Institut Teknologi Kalimantan Balikpapan Indonesia

ISBN: (数字)9798350368253

ISBN: (纸本)9798350368260

Classification of reliability values for Bus Rapid Transit (BRT) is very important to ensure services run smoothly and meet passenger expectations. Comparison of scaler variants is used in the KNN and DT algorithms to find a proposed classification model that is reliable and consistent. The DT and KNN (K=3 and Euclidean metric) algorithms use default parameters with 75% training data and 25% testing data, built with the Python programming language, and experiments using Jupyter Lab on macOS Venture 13.5. The purpose of this study is to find a classification model with the right scaler to classify the reliability of bus rapid transit. The use of a scaler changes the values of boarding, boarding per service hour, and punctuality in the dataset with large values in the scheme without a scaler, but the use of a scaler causes the values to decrease to a smaller extent. The DT algorithm with a standard scaler was found to be the most reliable and consistent classification model for BRT reliability values based on accuracy values. The use of appropriate algorithms and scalers is a finding to avoid classification data errors as seen from the data distribution and increase accuracy values.

关键词： Accuracy Training data Euclidean distance Nearest neighbor methods Reliability engineering Classification algorithms Reliability Standards Testing Python

Experimental Study on the Tunneling-Induced Deformation Characteristics of the Pile-Raft Foundations of High-Speed Railways

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SSRN 2023年

作者： Hu, Botao Shan, Yao Zhao, Yu Wang, Binglong Shunhua, Zhou Ma, Wenjie Detmann, Bettina Key Laboratory of Road and Traffic Engineering of The Ministry of Education Tongji University Shanghai200092 China Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety Shanghai200092 China College of Civil and Transportation Engineering Shenzhen University Shenzhen518060 China Department of Civil Engineering Faculty of Engineering University of Duisburg-Essen Essen45141 Germany

Tunneling beneath the pile-raft foundations of high-speed railways is inevitable in some situations and may induce unexpected or unfavorable deformation of pile foundations, which directly threatens the safety of passing trains. Because the mechanism of the tunneling-induced disturbance of pile-raft foundations is unclear, tunneling beneath the earthwork of high-speed railways is still prohibited in China. An understanding of the tunneling-induced deformation characteristics of piles and soil is required to evaluate the impact of tunneling beneath pile-raft foundation. Two-dimensional tunneling model tests were conducted to study the deformation characteristics of a pile-raft foundation induced by tunneling in this study. Particle image velocimetry and displacement transducer were used to measure the soil displacement and pile settlement, respectively. The evolution of pile settlement and deflection ratio of the pile-raft foundation with varying the tunnel-pile distances, ground surface loads, and tunnel volume loss were monitored to identify the main effects of the tunnel-pile interaction. Results indicate that tunneling-disturbed area in pile-raft foundation is larger than that in the greenfield. The maximum settlement of pile decreases with increasing burial depth of the tunnel beneath the pile. The ground surface load has a limited effect on the maximum settlement of pile, whereas tunneling-disturbed area expands with an increasing load. © 2023, The Authors. All rights reserved.

关键词： Piles

Shear Mechanism of Steel-Asphalt Interface Using Three-Dimensional Discrete-Continuous Coupling Method on the Mesoscopic Scale

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SSRN 2022年

作者： Liu, Yun Zhao, Xinyuan Xia, Guanglin Wang, Weiwei Road Railway Engineering Research Institute Hohai University Nanjing210098 China Intelligent Transportation System Research Center Southeast University Nanjing211189 China Suzhou Highway Bureau Suzhou215007 China

To investigate the shear failure mechanism of steel-asphalt interface (SAI) on the mesoscopic scale, the three-dimensional (3D) discrete-continuous coupling (DCC) method was adopted to carry out virtual direct shear tests (DSTs) at two temperatures of 30℃ and 60℃, and the results were compared with laboratory tests. According to the virtual test results at 30℃, the shear stress-displacement curves and the meso-cracks versus shear displacement were obtained. Then the variation of the mesoscopic force of SAI and the number and distribution of interlaminar meso-cracks with the development of shear displacement were shown. Meanwhile, the influence of temperature on the development of meso-cracks was investigated. The results show that the virtual test and the laboratory test have a good agreement on the relationship between shear stress and displacement, which verifies the reliability of the DCC model. The mesoscopic tension force (MTF) and mesoscopic compression force (MCF) of SAI go through a process of initially occurring, then increasing, and finally decreasing to almost 0. The development of meso-cracks has also experienced from slow to fast, and then unchanged. And the distribution is first generated near the loading wall, and then gradually overspread the SAI. Higher temperature can delay the development of meso-cracks. © 2022, The Authors. All rights reserved.

关键词： Asphalt

Long-Term Settlement of Metro Viaduct Piers: A Case Study in Shanghai Soft Soil

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SSRN 2023年

作者： Xiao, Junhua Shan, Jie Wu, Nan Liu, Mengbo Wan, Hongyu Sun, Siqi Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety Tongji University Shanghai201804 China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji University Shanghai201804 China College of Smart Manufacturing and Intelligent Transportation Suzhou City University Suzhou215104 China

The long-term settlement behavior of metro viaduct piers in soft soil in Shanghai was investigated in this study. The field monitoring of this project lasted for eight years, from its official opening to 2021, and showed that the settlement rate was greater in the first few years and gradually reduced since 2017. Up to 2021, the maximum cumulative settlement St was 15.9 mm (0.8 Ut, that is, 0.8 times the limit of St), and seven settlement troughs were observed. Muddy soil and rivers influenced the long-term pier settlement. St decreased proportionally with the thickness of the muddy soil. St of piers in and near the river were greater than those of adjacent piers, with a maximum settlement difference of 0.28-0.42 Ut. The influence range of the river on St was 3-4 Wr (width of river). Besides, St of piers with tubular piles were larger than those of piers with bored piles. Settlement differences mainly occurred in the first two years after completion. In the same situation, St of piers with tubular piles were 0.28 Ut (5.5 mm) larger than those of piers with bored piles on average. In addition, the slope k between the excavation-induced pier settlement and ratio of excavation depth to distance was closely related to the type of retaining structure. The ratio of k values with pit wall soil reinforcement, row piles and diaphragm wall is about 4:2:1. For foundation pits adjacent to metro piers under similar geological conditions, a more rigid retaining structure should be used, and the use of a soil-reinforced enclosure for the pit wall should be avoided. © 2023, The Authors. All rights reserved.

关键词： Piers

Anti-bullying Adaptive Cruise Control: A proactive right-of-way protection approach

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arXiv

arXiv 2024年

作者： Hu, Jia Lian, Zhexi Wang, Haoran Zhang, Zihan Qian, Ruoxi Li, Duo So, Jaehyun Zheng, Junnian Key Laboratory of Road and Traffic Engineering The Ministry of Education Tongji University No.4800 Cao’an Road Shanghai201804 China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha410082 China Shanghai Motor Vehicle Inspection Certification and Tech Innovation Center Co. LTD 68 South Yutian Road Shanghai201805 China University College London 25 Gordon Street London United Kingdom Department of Civil and Geospatial Engineering Newcastle University Newcastle upon TyneNE1 7RU United Kingdom The Department of Transportation System Engineering Ajou University Gyeonggi Suwon16499 Korea Republic of Co. Ltd. No.488 Anchi Rd Shanghai201805 China

The current Adaptive Cruise Control (ACC) systems are vulnerable to "road bully" such as cut-ins. This paper proposed an Anti-bullying Adaptive Cruise Control (AACC) approach with proactive right-of-way protection ability. It bears the following features: i) with the enhanced capability of preventing bullying from cut-ins;ii) optimal but not unsafe;iii) adaptive to various driving styles of cut-in vehicles;iv) with real-time field implementation capability. The proposed approach can identify other road users’ driving styles online and conduct game-based motion planning for right-of-way protection. A detailed investigation of the simulation results shows that the proposed approach can prevent bullying from cut-ins and be adaptive to different cut-in vehicles’ driving styles. The proposed approach is capable of enhancing travel efficiency by up to 29.55% under different cut-in gaps and can strengthen driving safety compared with the current ACC controller. The proposed approach is flexible and robust against traffic congestion levels. It can improve mobility by up to 11.93% and robustness by 8.74% in traffic flow. Furthermore, the proposed approach can support real-time field implementation by ensuring less than 50 milliseconds computation time. Copyright © 2024, The Authors. All rights reserved.

关键词： Traffic congestion

Anti-bullying Adaptive Cruise Control

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Anti-bullying Adaptive Cruise Control

IEEE Symposium on Intelligent Vehicle

作者： Zhexi Lian Haoran Wang Zihan Zhang Ruoxi Qian Duo Li Jaehyun So Jia Hu Key Laboratory of Road and Traffic Engineering of the Ministry of Education Tongji University Shanghai China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University Changsha China Shanghai Motor Vehicle Inspection Certification and Tech Innovation Center Co. Ltd Shanghai China Mathematics Department University College London London United Kingdom Department of Civil and Geospatial Engineering Newcastle University Newcastle Upon Tyne UK Department of Transportation System Engineering Ajou University Suwon Gyeonggi South Korea

ISBN: (数字)9798350348811

ISBN: (纸本)9798350348828

The current adaptive cruise control (ACC) systems are susceptible to disruptive behaviors such as mandatory cut-ins, commonly known as "road bullying". To address this issue, this paper introduces an anti-bullying adaptive cruise control (AACC) approach endowed with proactive right-of-way protection capabilities. It bears the following features: i) with the capability of preventing bullying from mandatory cut-ins; ii) with real-time field implementation capability. The proposed approach utilizes inverse optimal control (IOC) technology to discern the driving styles of other road users online, subsequently employing Stackelberg competition for motion planning. Extensive simulation results demonstrate the efficacy of the proposed approach in thwarting bullying from mandatory cut-ins. Additionally, the approach exhibits support for real-time field deployment by maintaining computation times of less than 50 milliseconds.

关键词： Adaptive systems Intelligent vehicles roads Simulation Optimal control Real-time systems Planning

A machine learning approach to identify rail corrugation and wheel polygon with the vehicle’s vibration and noise signals

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Tribology International 2025年 211卷

作者： Xinwen Yang Zhiang Sun Yingjie Zhang Shanghai Key Laboratory of Rail Infrastructure Durability and System Safety College of Transportation Tongji University Shanghai 201804 China Key Laboratory of Road and Traffic Engineering of the Ministry of Education College of Transportation Tongji University Shanghai 201804 China

The periodic wear of rails and wheels is highlighted as a significant issue in the maintenance of the vehicle-track system in urban rail transit. In this study, a machine learning method for the identification of rail corrugation and wheel polygon was proposed with the application of Back Propagation Neural Network (BPNN). The vehicle-track coupled dynamics model (VTCDM) was built to acquire axle-box acceleration, and the boundary element model was employed to acquire wheel-rail rolling noise. These data jointly constituted the dataset for training the BPNN. Both the theoretical model and field measurement of wheel-rail periodic wear were employed as excitation for the VTCDM to demonstrate the validity of the proposed method. The results indicated that the prediction model typically performed well and demonstrated enhanced applicability in the case of periodic wear with wavelengths surpassing 50 mm, exhibiting an error rate of 9.45 %.

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