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20 January 2025, Volume 44 Issue 1 Previous Issue   
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Transportation Infrastructure Engineering
Transportation+Big Data & Artificial Intelligence
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Transportation Infrastructure Engineering

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Measured Carbon Emission Factors of Geosynthetics Based on Production Processes XU Chao1,2, CHEN Mingming1, YANG Yang1,2, LI Geye1 2025, 44(1): 1-7.  DOI: 10.3969/j.issn.1674-0696.2025.01.01 Abstract ( )   PDF (6977KB) ( )   As a new type of building material, geosynthetic materials provide innovative solutions for geotechnical engineering problems and exhibit prominent advantages in energy conservation and emission reduction. However, currently, when calculating and evaluating the carbon footprint of geosynthetic materials engineering, it is rare to use the actually measured carbon emission factors of geosynthetic material products; instead, which is always based on the indirect estimation of relevant databases and literature. Thereby, it fails to truly reflect the hidden carbon of geosynthetic material products and also affects the accuracy and credibility of carbon footprint testing results. Aiming at the three types of most commonly utilized geosynthetic products including geotextiles, geomembranes and geogrids, on-site research on three domestic production enterprises was carried out. The lifecycle process analysis method was adopted to measure the carbon emission factors of geosynthetic products with different specifications from raw materials to final production. The results indicate that the carbon emission factor of plastic stretched geogrids is directly proportional to their tensile strength, while the carbon emission factor of geomembranes is closely related to their thickness. The primary component of the carbon emission factor for geosynthetic materials is the hidden carbon in the raw materials. References | Related Articles | Metrics

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Fatigue and Fracture Behavior Mechanism of Asphalt Based on Damage Tolerance Design Theory: Feature Discrimination,Mechanistic Criterion and Performance Prediction WANG Chao, SUN Yanguang, REN Zhengyang 2025, 44(1): 8-16.  DOI: 10.3969/j.issn.1674-0696.2025.01.02 Abstract ( )   PDF (2138KB) ( )   A systematic study was conducted on the feature discrimination, mechanistic criterion and performance prediction of asphalt fatigue crack initiation and propagation, which was based on damage tolerance design theory and took asphalt fatigue and fracture behavior mechanism as the research object. The peak value of energy release rate was used as the failure criterion for materials, and a feature discrimination method for the initiation and propagation behavior of asphalt fatigue cracks was proposed. The mechanistic criteria for the crack initiation and propagation phases were established by means of the damage mechanics and fracture mechanics, respectively. The prediction methods for the crack initiation life and crack propagation life were also developed. The proposed analysis method helps to refine the understanding and characterization of the fatigue and fracture processes of asphalt. References | Related Articles | Metrics

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Suitability Evaluation Method of Existing Facilities in Mountain Tunnels Based on IAHP GAO Jianzhang1, QI Jianbo1, XI Jingjun2, LI Zengcai2, WANG Yu3, CAO Yuguang3 2025, 44(1): 17-24.  DOI: 10.3969/j.issn.1674-0696.2025.01.03 Abstract ( )   PDF (1146KB) ( )   Accurately assessing the suitability of existing facilities within mountain tunnels is the core of reusing existing tunnels to lay new pipelines. In response to the current lack of evaluation methods for the suitability evaluation of existing facilities in mountain tunnels in China, the improved analytic hierarchy process (IAHP) was introduced into the evaluation process. An evaluation index system for the suitability of existing facilities in mountain tunnels was established, which comprehensively considered factors before and after reuse. Addressing the shortcomings of the nine-point scale method and the three-point scale method, the index scale method was adopted to determine the weight of each index. Combined with quantitative or qualitative evaluation methods for each index, an evaluation method for the suitability of existing facilities in mountain tunnels was proposed. The proposed method was applied to the reuse evaluation of mountain tunnels in practical engineering. The research results indicate that the evaluation results are consistent with the conclusions of actual engineering situations, which verifies the feasibility of the proposed evaluation model. References | Related Articles | Metrics

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Influence of Coarse Aggregate Morphology on the Anti-slip Performance of Asphalt Pavement WANG Hainian1, LI Yingkai1, WANG Huimin2, LI Lian1, SONG Haoran1 2025, 44(1): 25-32.  DOI: 10.3969/j.issn.1674-0696.2025.01.04 Abstract ( )   PDF (5379KB) ( )   In order to further clarify the relationship between the morphology characteristics of coarse aggregate and the skid resistance performance of asphalt pavement, based on the AIMS II equipment, the morphology indexes of the coarse aggregates with 3 kinds of lithologies and 4 kinds of shaping degrees such as gradient prism, texture index, sphericity, and morphology comprehensive indexes were obtained. And the pendulum friction meter and the laser scanner were used to obtain anti-slip performance evaluation indexes such as BPN20, the average tectonic depth MTD, the morphology parameter and fractal dimension indexes of the asphalt mixture surface layer. The relationship between the morphology indexes of coarse aggregate and the anti-slip performance evaluation indexes of asphalt mixture surface layer was established by Pearson correlation coefficient method. The results show that the weighted expected gradient prism value of the mixed coarse aggregate has a large correlation with the BPN20 value of the pavement, and the correlation coefficient reaches more than 0.9. It is recommended that the gradient prism value of the coarse aggregate should be increased before the construction, so as to ensure that the asphalt pavement has a reliable anti-slip performance. The research results are useful for further improving the anti-slip performance of asphalt pavement. References | Related Articles | Metrics

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Influence of Configuration of Steel Box Girder on Temperature Effect Considering Wind-Temperature Coupling HUANG Xu1, HE Jiajun1, DING Wenlong1, ZHU Jin2, LI Yongle2 2025, 44(1): 33-42.  DOI: 10.3969/j.issn.1674-0696.2025.01.05 Abstract ( )   PDF (7855KB) ( )   In order to accurately analyze the influence rule of the configuration of steel box girders on the temperature characteristics of the cross-sections, a finite element analysis method that considered the interaction between the local wind field and temperature field surrounding the steel box girder was proposed. The reduction coefficient k was used to establish the corresponding relationship between the wind speed Ua at the height of the thermal boundary layer around the steel box girder and the wind speed U measured at a distant meteorological station. Comparative analysis was conducted on whether the influence of wind-temperature coupling on the temperature distribution of steel box girder cross-sections was considered. The influence rule of different nozzle forms, cross-sectional aspect ratios, railing forms and pavement thickness on the temperature distribution of the steel box girder was discussed. The research results indicate that the wind speed Ua at the thermal boundary layer thickness around the steel box girder displays an uneven distribution and is linearly and positively correlated with the distant wind speed U. Not considering the wind-temperature coupling will significantly underestimate the surface temperature of the top plate of the steel box girder. The air nozzle, aspect ratio, railing parameters, and pavement thickness of the steel box girder section will all affect the temperature distribution of the cross-section, changing the temperature difference of the section. Thus, in the design of bridges, the influence of configuration of steel box girder on temperature distribution of cross-sections should not be ignored. References | Related Articles | Metrics

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Safety State Assessment Method of Long-Span Bridges Based on TIFANP-TOPSIS-TIFCE Method CHANG Longfei1,2, WU Yang3, WANG Chen1,2, RAN Bingchuan4, ZHENG Feng4 2025, 44(1): 43-54.  DOI: 10.3969/j.issn.1674-0696.2025.01.06 Abstract ( )   PDF (5779KB) ( )   Aiming at the problem of uncertainty of sub-indicators in traditional methods, a safety state assessment method for long-span bridges was proposed, which was based on triangular intuitionistic fuzzy analytic network process (TIFANP), technique for order preference by similarity to an ideal solution (TOPSIS) and triangular intuitionistic fuzzy comprehensive evaluation (TIFCE). Firstly, the hierarchical indicator system for the safety state of long-span bridges was established, and the TIFANP method was used to determine the weights of the indicators after considering their mutual influence. Subsequently, the TOPSIS method was introduced to allocate the weights of each section of the indicators, thereby obtaining the values of sub-indicators. Then, the safety state of the bridge was divided into 5 levels, and the membership and non-membership functions of the indicators at different levels were constructed by the TIFCE method. On this basis, the corresponding judgment matrices were established, and the comprehensive calculation of the bridge safety state indicators was carried out. Finally, the effectiveness of the proposed method was verified by the monitoring data from a certain long-span suspension bridge. The results show that the proposed method can deal with the interactions between the evaluation indicators and the uncertainty of the experts’ scoring in a more reasonable way, which can provide a new idea for the accurate assessment of the safety state of long-span bridges during the operation period. References | Related Articles | Metrics

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Secondary Development of Multi-scale Model for ABAQUS Warren Steel Truss Girder Based on Python TIAN Liang1,2,3, ZHANG Chengzhi1, SI Zhiyuan1, CHENG Bin4, FAN Lilong2 2025, 44(1): 55-61.  DOI: 10.3969/j.issn.1674-0696.2025.01.07 Abstract ( )   PDF (5441KB) ( )   The Warren-type steel truss girder is currently the most commonly used stiffening girder for large-span railway suspension bridges. However, due to its complex structural form and the continuous increase of bridge span, the modeling process has become cumbersome. In order to enhance the preprocessing efficiency of multi-scale models, a rapid modeling plug-in for Warren-type steel truss girders and bridge decks was developed on the basis of Python language. The parameterized modeling of steel truss girder segments was realized by the interaction between kernel-executed code and the ABAQUS GUI graphical interface. Taking the SQ railway suspension bridge under construction in the southwest canyon area of China as an example, a multi-scale finite element model of the entire bridge was established. Wind resistance verification was carried out in the typical steel girder segment hoisting process, and the results were compared with those obtained by the finite element software MIDAS and ANSYS. The trend of wind-induced displacement response at different hoisting heights was found to be generally consistent, with small errors. The research results demonstrate that all the preset functions of the developed rapid modeling plug-in can be implemented normally, greatly improving the modeling efficiency of complex steel truss girder structures while ensuring calculation accuracy. References | Related Articles | Metrics

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Measured Dynamic Stress of Asphalt Pavement under the Action of Heavy-Duty Truck DONG Pengjun1, CAO Xuejuan2, TANG Boming1, YUAN Ying2 2025, 44(1): 62-67.  DOI: 10.3969/j.issn.1674-0696.2025.01.08 Abstract ( )   PDF (2946KB) ( )   To reveal the variation law of the dynamic response of asphalt pavement under the action of heavy-duty trucks, the spatiotemporal distribution of vertical dynamic stress in the pavement structure was studied, which took two kinds of semi-rigid base asphalt pavements such as the ring structure 7 and structure 8 of the RIOHTrack full-scale test track as the research objects. The results indicate that under the action of multi-wheel heavy-duty trucks, as the depth of the pavement deepens, the vertical dynamic stress peaks appear to overlap. The greater the strength of the base material, the smaller the depth from the road surface to the position where the vertical dynamic stress peaks completely overlap. The vertical dynamic stress fluctuates in a zigzag pattern along the depth direction of the subgrade and pavement. Among them, in the upper base layer, the vertical dynamic stress attenuation is the most obvious, and the peak value of the vertical dynamic stress wave attenuates by more than 90% relative to the peak value of the bottom wave of the lower layer. At the bottom of the lower layer, the accumulated stress is relatively high, which can easily cause fatigue failure. Along the depth direction of the pavement, under the influence of stress diffusion and material damping, the vehicle load firstly reaches the subgrade and has the longest duration of action in the subgrade. References | Related Articles | Metrics

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Stability Evaluation Model of Cantilevered Dangerous Rock Based on Natural Frequency LIU Weinan, SONG Hongke 2025, 44(1): 68-74.  DOI: 10.3969/j.issn.1674-0696.2025.01.09 Abstract ( )   PDF (2905KB) ( )   In response to the difficulty of evaluating the stability of cantilevered dangerous rock mass, the relationship between the stability of the cantilevered rock mass and the length of their rock bridges was analyzed. The formula for the relationship between the length of the rock bridge and the vibration frequency of the rock mass was given, and the theoretical calculation formula for the natural frequency of cantilevered dangerous rock mass was derived, and a stability evaluation model for cantilevered dangerous rock mass based on the dynamic index of natural frequency was established. Indoor model experiments were conducted to investigate the failure of cantilevered dangerous rock mass. It is indicated that reducing the length of the rock bridge of cantilevered dangerous rock mass will cause a decrease of its natural frequency. It is found that there are differences in the natural frequencies of different vibration modes in the stability evaluation of dangerous rock masses. The calculation formula for the natural frequency of dangerous rock masses has been adjusted with the combination of the experimental results. The experiment results demonstrate that the natural frequency of cantilevered dangerous rock mass can serve as a calculation index of stability. For the proposed experiment, the modified formula for calculating the natural frequency of cantilevered dangerous rock mass exhibits an accuracy of over 90%, in which the stability of dangerous rock mass prior to damage is calculated by the natural frequency of vibration in the vertical plane of dangerous rock mass. References | Related Articles | Metrics

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Literature Review of Electrical Resistivity Model of Soil-Rock Mixture CHEN Songlin1, WANG Kui1, ZHAO Mingjie1, 2 2025, 44(1): 75-85.  DOI: 10.3969/j.issn.1674-0696.2025.01.10 Abstract ( )   PDF (4862KB) ( )   The electrical resistivity method can detect and characterize the internal structure and characteristics of porous media such as soil and rock through surface conductivity, so it is widely used in the in-situ tests. Soil-rock mixture (S-RM) is an extremely uneven and loose rock and soil medium system composed of multiphase media, and the conductivity of S-RM is influenced by the spatial distribution, conductivity and combination modes of each media. A large number of scholars have carried out experimental and theoretical studies on soil resistivity, and various theoretical models of soil resistivity have been summarized. Due to the late start of research on the electrical resistivity characteristics and related theories of S-RM, the conductivity mechanism of S-RM was analyzed on the basis of the soil electrical resistivity model, and the existing electrical resistivity models of S-RM and their limitations were summarized. The results indicate that the conductive principle of the mixed medium lays the foundation for the study of electrical conductivity models of S-RM. Based on the electrochemical theory, there is a mature theory for the conductivity of single-phase media, while the conductivity model of multiphase media is still being continuously improved and perfected. The existing electrical resistivity models for S-RM can be divided into series-parallel connection model and regional statistical model. The regional statistical model is mostly empirical formula, which is convenient to apply, but the generalizability of the model still needs to be improved. The series-parallel connection model has a good theoretical foundation, and the physical meanings of parameters in the model are clear. However, simplifying the conductive medium into a series-parallel arrangement is still different from the complex internal structure of S-RM, and the model still needs further improvement. References | Related Articles | Metrics

Transportation+Big Data & Artificial Intelligence

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Resilience Evaluation and Key Factors Identification of Sea Lanes LÜ Jing, WANG Jiaxin, FAN Hanwen 2025, 44(1): 86-95.  DOI: 10.3969/j.issn.1674-0696.2025.01.11 Abstract ( )   PDF (2315KB) ( )   The safety and unimpeded passage of sea lanes is the core guarantee for the stable development of the maritime transport industry. In order to evaluate the resilience level of sea lanes scientifically, a resilience evaluation framework based on principal component analysis, fuzzy logic and Bayesian network model was proposed. Firstly, by analyzing the relevant accident reports and literature, the key factors affecting the resilience level of sea lanes was identified on the basis of the dually driven perspective. Then, in order to make up for the defects of the correlation between the influencing factors and fully mine the sample information, principal component analysis was used to screen the initial indexes. Finally, the index weights obtained by principal component analysis were used as the quantitative input of the interrelationships between influencing factors in Bayesian networks, thus taking into account the importance of influencing factors and effectively overcoming the defect of ignoring the importance of indexes in traditional Bayesian networks. The research results show that the proposed resilience evaluation framework can measure the resilience level of sea lanes more effectively than other evaluation methods do, which provides an important theoretical basis and decision-making reference for the resilience evaluation of sea lanes. References | Related Articles | Metrics

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Optimization of Emergency Evacuation Plan for Subway Stations during Peak Hours Based on Evacuation Guidance TIAN Jie, SU Yupeng, WU Tong, ZHU Zhenjun 2025, 44(1): 96-103.  DOI: 10.3969/j.issn.1674-0696.2025.01.12 Abstract ( )   PDF (9215KB) ( )   In order to ensure the efficiency and safety of pedestrian emergency evacuation in subway stations during peak hours in case of sudden accidents, the existing evacuation scheme was optimized. Firstly, the characteristics of pedestrian evacuation in subway stations during peak hours were analyzed, the necessity of adding evacuation guidance during peak hours was clarified, and the common bottleneck congestion points in evacuation were summarized. Subsequently, evacuation guidance measures were designed for the location of each bottleneck congestion point, and the existing evacuation plan and the optimization plan after adding evacuation guidance were designed respectively. Finally, two kinds of evacuation schemes were simulated by Anylogic software, and multiple evacuation evaluation indexes were compared and analyzed to verify the effectiveness of the optimization scheme. The research shows that the existing evacuation scheme can complete the evacuation on time during off peak hours, but its total evacuation time during peak hours exceeds the 360 seconds required by subway safety evacuation regulations. While the total evacuation time of the optimization scheme during the peak hours is 352 seconds and the longest passing time of the gate is 278 seconds, which are both better than those of the existing evacuation schemes. The research results can provide reference for the specific design of evacuation guidance in the evacuation plan of subway stations during peak hours. References | Related Articles | Metrics

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Collaborative Adaptive Cruise Control Strategy for Heterogeneous Fleet Based on Fuzzy MPC FENG Li, GAO Ruohan 2025, 44(1): 104-111.  DOI: 10.3969/j.issn.1674-0696.2025.01.13 Abstract ( )   PDF (1768KB) ( )   Taking the heterogeneous fleet consisting of electric vehicles with different dynamic parameters as the research object, a cooperative adaptive cruise control (CACC) system utilizing fuzzy control theory to modify the fixed weights of the original model predictive control (MPC) was proposed, which aimed to meet the performance requirements of the mixed heterogeneous traffic flow such as following, safety and comfort. The longitudinal dynamic models between the vehicles in the CACC system were constructed, and a discrete-state space equation was established. Corresponding objective optimization functions were created and solved with constraints. Fuzzy rules were designed to change the fixed weight coefficients of MPC related performance. Finally, a joint simulation model combining Simulink and CarSim was constructed for testing. Experiment results demonstrate that the improved fuzzy MPC control algorithm outperforms the traditional MPC control algorithm in terms of control effect under the following driving conditions, which can better respond to the performance of heterogeneous fleet such as following, safety and comfort, and better meet the actual driving situation of vehicles. References | Related Articles | Metrics

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Characteristic Analysis of Axle Box Spring of EMU Considering Contact Influence HUO Yongfeng, XUE Hai, ZHANG Yufan, YE Cenglin 2025, 44(1): 112-119.  DOI: 10.3969/j.issn.1674-0696.2025.01.14 Abstract ( )   PDF (8852KB) ( )   In response to the problem of insufficient stiffness and service life caused by the contact between the working ring and the support ring of EMU axle box spring, as well as the disadvantage of using traditional integrated scanning modeling difficultly to achieve the flat and tight features of the two end support rings, a three-stage modeling method of “lower support ring-upper support ring-working ring” was proposed according to the topological relationship of the geometric structure of the spring. The Python secondary development module of the finite element software ABAQUS was used to establish a refined finite element model of the axle box spring, thereby improving the accuracy and parameterization of the model. Considering the influence of the contact effect between the working ring and the support ring, a simulation analysis of spring characteristics was carried out from the aspects such as contact area, stiffness and stress. The influence rule of the contact relation on the characteristics of the spring was clarified, and the accuracy of the simulation results was verified by experiments. The analysis results show that there is a phenomenon of warping in the middle section of the contact line between the working ring and the support ring. As the load increases, the contact area increases exponentially, and the stiffness also exhibits a significant nonlinear increasing characteristic. The stiffness under compressive load is 17.1% higher than that without contact. The contact relation has greater influence on the shear stress of the working rig near the support ring, while it has less influence on the middle part of the working ring. The maximum error between simulation value and theoretical value is 3.91%. The stiffness and inner shear stress simulated and analyzed by parameterized finite element model both have errors of less than 5% compared to the values tested by experiments, which indicates that the proposed modeling method is feasible and can provide reference for improving the design quality and service safety of EMU axle box spring. References | Related Articles | Metrics

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Modeling and Control Simulation of Integrated Heating System for Power Batteries LIU Gang, XU Jiannan, CHEN Tianyu, ZHANG Baolai 2025, 44(1): 120-126.  DOI: 10.3969/j.issn.1674-0696.2025.01.15 Abstract ( )   PDF (2946KB) ( )   In order to improve the performance of vehicle power battery in low temperature environment, a battery heating system with positive temperature coefficient (PTC) thermistor as the main heating source and the waste heat of the air conditioning system as the auxiliary heat source was designed. Based on the heat transfer process of the proposed system, a heat transfer mathematical model was established, and AMEsim and MATLAB software were used to establish a simulation model of the proposed system. The process of battery heating had the characteristics of large delay and slow response. In order to improve the response speed of the system, the control strategy of PTC and water pump motor was designed based on the model predictive control algorithm. The simulation results under CLTC-P condition show that the heating rate of the battery can be increased by using the waste heat of the air conditioner. Compared with PID control, the model predictive control reduces the working time of the heater by 106 seconds and the heating energy consumption by 0.07 kWh. References | Related Articles | Metrics