Table of Content

25 November 2024, Volume 52 Issue 11

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Architecture & Civil Engineering

Influence of Near-Field Acoustic Holography Reconstruction Parameters on the Accuracy of Sound Insulation Measurement



WANG Hongwei, ZHANG Guangyao, SHEN Tao, et al

2024, 52(11):  1-8.  doi:10.12141/j.issn.1000-565X.240029

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Equivalent source method near-field acoustic holography can be applied in sound insulation measurement of the building components. When near-field acoustic holography is used to measure the sound insulation volume of components, the reconstruction parameters significantly affect the acoustic field reconstruction results. Based on the theoretical analysis of near-field holographic acoustic insulation measurement by equivalent source method, the compound sound pressure signal of the surface of the component was measured by the microphone array, and the sound insulation volume and surface normal sound intensity distribution of the component were obtained through the acoustic field reconstruction. To further investigate the influence of reconstruction parameters on the accuracy of equivalent source method near-field acoustic holography, experiments on sound insulation measurement of building components were carried out in the sound insulation room by the control variable method in comparison with the traditional sound pressure method. The results show that when the position of the equivalent source surface changes from -2 cm to -5 cm, the average error value of the reconstruction of the surface normal sound intensity increases from 3.9 dB to 5.6 dB, and the average error value of the reconstruction of the sound insulation volume increases from 5.2 dB to 6.9 dB, and the measurement error increases with the distance of the equivalent source surface, so it is suitable for the equivalent surface to be close to the sound source surface. When the holographic measurement surface distance is 4, 8, and 16 cm, the average error values of the reconstruction of the surface normal sound intensity are 0.6, 1.9, and 5.5 dB, and the average error values of the reconstruction of the sound insulation volume are 0.9, 1.4, and 4.6 dB, respectively. The measurement errors increase with the holographic measurement surface distance, so it is recommended to keep the holographic measurement surface distance within 8 cm. When the number of equivalent source points is consistent with the number of measuring points on the holographic surface, the difference with the traditional sound pressure method is only 0.84 dB. When the number of equivalent source points is inconsistent with the number of measuring points on the holographic surface, the average error values of the reconstruction of the sound insulation volume and surface normal sound intensity distribution increase to 4.6~6.8 dB. By optimizing the reconstruction parameters, the accuracy of component sound insulation measurement can be effectively improved. It has important reference significance for laboratory measurement of sound insulation performance and methods of building components and has high reference value in the practical application of sound insulation measurement technology.

Experimental Study on Failure Mechanism of RC Frame Structures Based on Performance Design Method



LING Yuhong, HUANG Qianyi, ZHOU Jing, et al

2024, 52(11):  9-20.  doi:10.12141/j.issn.1000-565X.230648

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To verify the rationality, reliability and fault tolerance of the “two-level and two-stage” seismic performance-based design method of Guangdong standard DBJ/T 15-92—2021 “Technical specification for concrete structures of high-rise buildings”, this study designed two batches of 1∶4 scale plane RC frame structure specimens with the same seismic structure grade of first-level, second-level and third-level. During loading, iron counterweights were arranged on each floor to simulate the distributed load, and the influence of floor and floor load on the failure mechanism of frame structure was considered. The test adopted displacement-controlled single-point loading. The loading point is located at the elevation of the three-story floor beam. Before the longitudinal reinforcement of the column reaches the yield strain, it is single-cycle loading, and after the yield, it is three-cycle loading. Through the pseudo-static test, the seismic failure mode and failure mechanism of the structure were investigated, and the evolution law of seismic performance indexes such as hysteresis curves, ductility, stiffness and energy dissipation was analyzed. The test results show that the plastic hinge development paths of the specimen damage are basically the same, which conforms to the failure mechanism of the plastic hinge ductility mechanism at the beam end. The specimen has no obvious shear failure characteristics, and the bearing capacity utilization coefficient ξ can meet the seismic design requirements of “strong shear and weak bending”. The hysteresis curves of the six frame structure specimens are full, and the seismic ductility coefficient ranges from 4.36 to 6.10. The maximum value range of equivalent viscous damping coefficient is 0.125~0.165, which shows good seismic energy dissipation performance. The floor slab improves the stiffness and bearing capacity of the frame beam, which has a significant impact on the seismic failure mechanism of the specimen. The specimen maintains the seismic failure characteristics of “strong column and weak beam”, and the component importance coefficient η can ensure the seismic design requirements of “strong column and weak beam”. The failure characteristics of the specimens are random, but the overall regularity of the failure mechanism is strong, and the gradient characteristics of the specimens with different seismic structural grades are obvious.

Multi-Factor Model of Plastic Development Coefficient and Strength Calculation for Rectangular Concrete-Filled Steel Tube Members Under Pure Bending



PANG Mulin, XIE Weiwei, YANG Lufeng

2024, 52(11):  21-31.  doi:10.12141/j.issn.1000-565X.240059

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The constraint effect of rectangular steel pipe on core concrete has special characteristics, and the accurate prediction of the plastic development capacity of bending members can effectively ensure the load-bearing safety. In order to improve the calculation accuracy of the sectional strength of rectangular CFST members under pure bending, this study established a multi-factor model of plastic development coefficient and an improved bending strength model based on the confinement coefficient and further considering the influence of height-width ratio and steel ratio. First of all, based on the unified theory of CFST members, the change law of plastic development coefficient of rectangular concrete-filled steel tube was studied and compared with the current standard calculation formula. Then, combined with the specification and engineering needs, 2 160 numerical simulation components of rectangular CFST members under pure bending were constructed and the refined analysis of the fiber model method was conducted using the improved constitutive relationship and component failure criterion. The influence of width-thickness ratio, height-width ratio, steel ratio and strength ratio on plasticity development coefficient was investigated to determine that the height-width ratio and steel ratio are the main factors influencing the plasticity development coefficient, and the function expressions related to the height-width ratio and steel ratio were fitted through regression analysis. Thus the multi-factor model of plasticity development coefficient and strength calculation of rectangular CFST members under pure bending were established. Finally, the bending strength improvement model was verified against the main design specifications at home and abroad by using the 128 sets of experimental data collected. The results show that the established multi-factor model of plasticity development coefficient overcomes the defects of the current specification that the calculation model is not accurate enough, and it can more accurately reflect the plasticity development capacity of rectangular CFST members under pure bending. The established improvement model of the bending strength of rectangular CFST members under pure bending solved for the ratio of the ultimate load carrying capacity to the experimental value has a mean value of 0.971 and a root-mean-square error of 0.118, indicating a good match and a higher calculation accuracy.

Analysis of the Ultimate Bearing Capacity of the Π-Joint of Welded Square Tube Under Axial Load



LIU Yan, CHEN Yixian, WANG Xin, et al

2024, 52(11):  32-42.  doi:10.12141/j.issn.1000-565X.230790

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The current standards have not yet specified the formula for calculating the bearing capacity of Π-shaped welded square tube joints. Based on experimental validation of finite element analysis accuracy, this paper utilizes Abaqus software to numerically simulate 85 sets of joints under axial load, obtaining the ultimate bearing capacity of Π-shaped joints. Subsequently, parameter analysis and regression analysis were conducted to identify factors influencing the ultimate bearing capacity of Π-shaped joints and the modified calculation formula. The results show that the width ratio of branch pipe to main pipe β has a great influence on the ultimate bearing capacity and initial stiffness of the joint. Increasing the width of branch pipe can significantly improve the ultimate bearing capacity of the joint. The load imposed on the branch pipe is jointly borne by the bending and shear effects on the upper surface of the main pipe and the side wall of the main pipe. The failure mode of the joint also depends on β. The larger the width thickness ratio of the main pipe 2 γ, it means that the connection area between the upper flange of the main pipe and the branch pipe becomes more slender, which reduces the bending stiffness of the upper flange of the main pipe, and therefore reduces the bearing capacity and initial stiffness of the joint. The branch pipe to main pipe height width ratio η and the branch pipe spacing have a certain impact on the ultimate bearing capacity of the joint. Increasing the height of the branch pipe section and the branch pipe clearance, that is, increasing the intersection area of the branch pipe and the main pipe along the longitudinal direction of the main pipe, makes the branch pipe transfer load in the wider area of the main pipe flange. The plastic area of the node is larger and the material is more fully utilized, thus improving the carrying capacity of the node. The thickness ratio of branch pipe to main pipe τ has little effect on the ultimate bearing capacity and initial stiffness of the joint. The increase of the wall thickness of the branch pipe improves the bearing capacity of the branch pipe, but the ultimate failure of the joint is the yield failure of the upper flange of the main pipe rather than the failure of the branch pipe. Therefore, the change of the thickness of the branch pipe has no obvious effect on the bearing capacity of the joint. Based on the analysis results of the finite element model, a parameter equation for calculating the ultimate bearing capacity of welded square tube Π-shaped joints was proposed through curve fitting, and the accuracy of this equation was evaluated, providing a reference for further research and engineering applications of such joints.

Intelligent Method for Identifying Damage of Steel Members with Localized Random Pitting Based on Convolutional Neural Network



QIANG Xuhong, TIAN Weixiao, JIANG Xu, et al

2024, 52(11):  43-54.  doi:10.12141/j.issn.1000-565X.230685

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Pitting induced by the marine environment has a significant impact on the safety of steel structures and its form exhibits a strong multi-scale and multi-parameter randomness. In order to effectively detect and identify damage in actual engineering, this paper systematically investigates local random pitting of steel members via experimental study, numerical simulation, and theoretical analysis based on convolutional neural networks. Firstly, under the premise of following the distribution model of pitting corrosion pit depth and the time-varying model of pitting corrosion pit diameter, the boundary and cross restrictions were imposed on the position distribution of corrosion pits using multi-parameter local random pitting numerical model. Python was utilized to generate randomness in the size, location, and number of pits, allowing Abaqus to generate a large number of finite element models of steel plates with varying rust locations and rust rates, and the mode shape samples of each finite element model were obtained. Then, the finite element model was used as a test prototype, and a large number of samples of the first six-order vibration patterns obtained from numerical tests were used to train a convolutional neural network model for identifying damage location. The accuracy of the model was verified using the finite element data set. Finally, the vibration results of the ruler test were used to further verify the accuracy of the convolutional neural network model. The study shows that the model fully considers the randomness of pitting corrosion in aspects such as shape parameters and position coordinates. The parameters are reasonable, close to the actual pitting corrosion situation in reality, and the recognition accuracy is relatively high. In numerical tests, the model achieved 95.9% accuracy in identifying pitting damage to the real area and its adjacent areas, and 81.2% accuracy in full-scale tests, meeting the requirements for the practical intelligent application of identifying steel component damage.

Analysis on Shear Characteristics and Shear Strength of Unsaturated Granite Residual Soil



MA Qinguo, GUO Haogong, LUO Xiaoxiao

2024, 52(11):  55-68.  doi:10.12141/j.issn.1000-565X.230470

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This study carried out triaxial undrained consolidation tests on undisturbed and remolded granite residual soil with different water contents and comparatively analyzed the effect of saturation on shear deformation characteristics of undisturbed and remodeled soils.Firstly, it obtained the relationship between matric suction and shear strength index by measuring the soil-water characteristic curve and established the unsaturated shear strength expression of the granite residual soil. The results show that the degree of strain-hardening of the undisturbed and remodeled soils increases with the increase of water content and confining pressure. The stress-strain curves of the undisturbed soils are softening and the remodeled soils are hardening under low water content and confining pressure. The change pattern of stress path with water content is basically the same in undisturbed soil and remodeled soil. With the decrease of water content, pore water pressure gradually decreases during shearing process, and the effective stress path gradually approaches the total stress path. The soil-water characteristic curve of granite residual soil can be divided into three stages: saturation, transition and residual. During the dehumidification process, the residual suction of undisturbed soil is larger than that of remolded soil, and the transition area is larger than that of remolded soil. In the state of high saturation, the water contents of undisturbed and remodeled soils change little with the increase of matric suction and begin to decrease significantly with matric suction reaching the air-entry value, and the water contents change slowly in the residual stage. The influence of matric suction on the internal friction angle of soil is very small; the cohesion increases with the increase of matric suction; the adsorption internal friction angle decreases gradually; and the contribution of matric suction to the soil shear strength decreases gradually. The influence of matric suction on the effective cohesion of undisturbed soil and remodeled soil is much greater than the effective internal friction angle. The unsaturated hyperbolic model established by the regression relationship between matric suction and suction strength has a good applicability for predicting the unsaturated shear strength of residual granite soil.

Experimental Study on Vacuum Dehydration of Waste Silty Clay Slurry in Shield Tunneling



GAO Xinjun, WANG Jianbo, SU Qinghui, et al

2024, 52(11):  69-82.  doi:10.12141/j.issn.1000-565X.230736

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The waste silty clay slurry produced during shield construction has the characteristics of high water content, low strength and small particle size and it has difficulties in rapid consolidation. How to effectively dehydrate and cure is the key to reduce environmental pollution in the process of transportation or storage. Based on the self-developed waste slurry vacuum dehydration device, this study carried out indoor dehydration model tests under four different forms of dead weight, dead weight and vacuum, dead weight stabilization and vacuum, dead weight stabilization and graded vacuum. It analyzed the distribution laws of sediment-water interface settlement, pore water pressure, dehydration volume and residual slurry moisture content after dehydration of waste silty clay slurry under different loading modes. Finally, the dewatering effect of the waste silty clay slurry was compared under different loading modes. The test results show that among the four dewatering methods, the loading method of first dewatering the waste silty clay slurry by self weight, and then applying vacuum to the bottom part of the waste silty clay slurry has the best dewatering effect on the waste silty clay slurry, which can effectively reduce the water content of the waste silty clay slurry. After dewatering the waste silty clay slurry with initial water content of 97.50%, the water content distribution range is 28.21%~34.25%, and the minimum pore water pressure can reach -72.92 kPa. Meanwhile, based on the idea of segmented linearization, a one-dimensional dehydration theoretical analysis model for waste slurry was established. This model numerically simulates the sedimentation of the sediment-water interface during the dehydration process of waste silty clay slurry, and compares the results of numerical simulation with the test results. Then the optimal loading method was explored by simulation analysis of dehydration efficiency under different loading modes. This study can provide a theoretical and practical basis for the rapid dehydration treatment of shield waste silty clay slurry.

Intelligent Transportation System

Joint Prediction Model of Multi-Modal Transportation Passenger Flow Based on Hypergraph Convolution



WANG Jiangfeng, DING Weidong, LUO Dongyu, et al

2024, 52(11):  83-94.  doi:10.12141/j.issn.1000-565X.240064

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The traffic modes in metropolis is interwoven to form an interconnected passenger flow network, and the spatio-temporal relationship between cross-transportation modes is complicated, which requires the joint prediction of passenger flow to analyze the overall travel law. For the cross-transportation passenger flow network, the supergraph correlation matrix of cross-transportation modes is introduced to describe the correlation between the passenger flow supergraph network of bus and subway, and a joint prediction model based on dual-mode spatial-temporal supergraph convolution network (BSTHCN) is proposed. Specifically, the model consists of three parts: an input module, a spatio-temporal convolution module (including temporal and spatial convolutions), and an output module, which can simultaneously capture the passenger flow network characteristics of both buses’ and metros’ stations and routes, as well as the transfer passenger flow characteristics between the two different passenger flow networks. The proposed model can identify and extract important information features, and perform feature aggregation and allocation. The experimental results show that the proposed model has better prediction accuracy compared to classical prediction models. The proposed model reduces the mean absolute error (MAE) by 8.93% and 8.10% on the bus and metro datasets, respectively, while the RMSE decreased by 10.64% and 7.47%. Moreover, the parameter volume and model runtime of proposed model are within a reasonable range. Compared to S-TGCN and DCRNN, proposed model achieves more accurate predictions with only a 4.82% increase in runtime. On the whole, proposed model demonstrates strong competitiveness. The ablation experimental results further demonstrate that after incorporating hypergraphs and considering multi-modal transportation correlations, the proposed model can better reflect both local and global characteristics in passenger flow networks, thereby improving the accuracy of passenger flow prediction.

Optimization of Metro Feeder Bus Routes Based on Surrogate-Assisted NSGA-Ⅱ Algorithm



TANG Jinjun, REN Maoxin, LI Zhitao, et al

2024, 52(11):  95-105.  doi:10.12141/j.issn.1000-565X.230595

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The connection between urban rail transit and bus transit is the key to meet the various urban travel demand and to promote the development of urban public transportation system. Existing studies lack the consideration of some important micro-indicators, such as the ratio of waiting for multiple buses during peak hours and the level of congestion inside the bus, when constructing the optimization model. Additionally, there is a lack of consideration for the stochastic and heterogeneous requirements in route operation, which results in poor performance in practical applications. To address these issues, this study firstly established an optimization model based on the service process of the bus transit, with the objective of minimizing the travel cost of passengers and the cost of enterprises. The model considers the influencing factors such as operating speed, vehicle type, departure frequency, route fare, vehicle crowdedness, and route line type and it is solved by the non-dominated sorting genetic algorithm (NSGA-Ⅱ), in which the genetic operation part is improved. Furthermore, a microscopic simulation algorithm was designed to evaluate the solution in order to improve the accuracy of the model solution. Accordingly, a Kriging surrogate model was used to assist the calculation to improve the solution efficiency of the algorithm. Finally, taking the connection between metro and bus system in Shenzhen city as an example, the proposed algorithm was validated with the IC card data collected in metro and bus system. The sensitivity analysis was conducted for the factors of route fare, operating speed, operating mode and passenger volume, and the operating improvement was proposed based on the analysis results. The results demonstrate that the algorithm produces superior route solutions compared to the conventional NSGA-Ⅱ, with the same solving time. There is a 35.49% reduction in total cost and a notable 26.94% increase in the iteration speed. The optimization method for connecting between metro and bus transit proposed in this study has practical significance in improving connecting efficiency and operational level.

Evaluation of the Effect of Self-Luminous Road Marking in Expressway Weaving Section Based on Driving Behavior



ZHANG Ting, CHEN Feng, LI Huang, et al

2024, 52(11):  106-117.  doi:10.12141/j.issn.1000-565X.230762

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The active management and control strategy in the weaving section of expressways plays a crucial role in enhancing operational efficiency and improving driving safety. Self-luminous road marking is a new type of road traffic safety active control facility. Because of its intelligent control, virtual and real transformation, emergency warning and other functional characteristics, it has attracted more and more attention and gradually promoted and applied. In order to explore the effect of the new road marking in the expressway weaving area, based on the driving simulation test, this paper analyzed the influence characteristics of self-luminous road marking on driving behavior from the perspective of drivers and evaluated the effect of self-luminous road marking. Two simulation scenarios were designed: one with conventional road markings and the other with self-luminous road markings under nighttime conditions. Driving behavior data were collected, and six indicators were selected to construct an evaluation system, focusing on driving safety, comfort, and driver control performance. These indicators include standard deviation of speed, standard deviation of lateral position, root mean square of longitudinal acceleration, standard deviation of acceleration, mean speed, and throttle effectiveness. Further analysis was conducted to examine the significance of differences and effect size levels of various indicators under different road marking scenarios. Finally, an extension matter-element model was applied to construct a comprehensive evaluation model to compare the effects of the two road marking schemes. The results indicate that self-luminous road markings significantly influence driving behavior characteristics in weaving sections. Under the self-luminous marking condition, drivers’ lateral position perception and control levels is improved, speed regulation ability is increased, and vehicle movement becomes more stable. The comprehensive evaluation based on the extension matter-element model shows that self-luminous road markings are more effective than conventional road markings in enhancing driving safety in expressway weaving sections.

Improvement Effectiveness of Active Warning Prevention and Control Strategy for Operation Risk on Foggy Bridges



DAI Yibo, ZHAO Xiaohua, BIAN Yang, et al

2024, 52(11):  118-133.  doi:10.12141/j.issn.1000-565X.230757

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In order to improve traffic operation of freeway bridge sections in fog, this paper proposed a human factor-oriented operation risk active warning prevention and control strategy for bridges. This strategy integrates traditional traffic safety facilities with intelligent technologies such as risk warning, dynamic speed limits, and visual guidance. Through changes in prevention and control levels under different risk levels, the facility resources were fully utilized to achieve the goal of multi-level and differentiated prevention and control from static notification to dynamic guiding. However, it is not yet clear whether this process will improve the driving behavior and the safety and efficiency of traffic operation, so it is difficult to support the effective design and application of the prevention and control strategy. Therefore, E’dong Yangtze River Bridge was taken as an example to quantitatively evaluate the improvement effectiveness of the prevention and control strategy through driving simulation test and to verify its validity. The optimization and implementation is based on the fact that human factor needs are subjected to the prevention and control strategy, then it has a better effect in guiding the practical application. The improvement effectiveness evaluation of prevention and control strategy was realized through the improvement rate of each indicator from three aspects (psychological perception, safety effectiveness and traffic efficiency). The results show that the prevention and control strategy is helpful to improve driver’s confidence and alleviate tension; it can significantly improve the driver’s behavioral performance and traffic operation state and enhance the traffic efficiency and the safety of horizontal and longitudinal operation of vehicles; it has the strongest ability to improve safety effectiveness, especially at the longitudinal level; the higher brightness line-of-sight induction strategy is more conducive to improving the safety level and significantly increasing the traffic capacity. Compared with the low brightness condition, it may have a negative impact on the driver’s psychological feelings, but it is not obvious. When the visibility is 100 m on bridge, it is recommended that the flashing frequency of visual guidance technology is 0.5 Hz and the brightness is 3 500 cd/m². The results provide the necessary theoretical basis for the practical application of prevention and control strategy on foggy bridges. The proposed solution and the analytical idea of its improvement effectiveness provide a reference for targeted prevention and management of risky sections.

Research on the Construction and Evaluation Methods of the Perceptual Space of Unmanned Vehicles



WANG Xiaofei, WANG Ziqi, DING Zhenzhong, GUO Yueli, YAO Jiangbei

2024, 52(11):  134-140.  doi:10.12141/j.issn.1000-565X.230777

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The sensor of unmanned vehicles replaces human eyes to perceive the information of road space is an important prerequisite for the safe operation of unmanned vehicles. Therefore, based on the domestic and international research literature research as well as the analysis of relevant software and hardware technologies, this paper analyzed the limitations of the current perception technology of unmanned vehicles, including the recognition range and characteristics of sensors such as LiDAR, camera and millimeter-wave radar. And it collected the real information of the road by using the LiDAR and the combination of navigation system, and further constructed the three-dimensional perception space of the unmanned vehicle with the collected point cloud data, the localization information, and the synchronous positioning and modeling algorithms, which realize the three-dimensional digital model construction of the road. At the same time, the mathematical expression model construction of parameters such as ranging ability, horizontal field of view angle and vertical field of view angle was carried out in the 3D point cloud map, and the spatial coordinate transformation method was utilized to separate the 3D point cloud data within the recognition range of the sensors and convert them to a unified coordinate system. Finally, the Delaunay triangulation method was used to construct a 3D model that can reflect the characteristics of perceptual space, so as to realize the perceptability of 3D perceptual space. In order to verify the practicality and accuracy of this method, this paper tested the algorithm using data collected in the field. The test results show that the method proposed in this paper has good robustness and it can work stably in complex road environments and accurately assess the perceptibility of unmanned vehicles. This research result not only provides a scientific basis for the road design and safety assessment of unmanned vehicles, but also provides strong technical support for the further development and application of unmanned technology.

Analysis on Crosswind Effects of a High-Speed Train Breaking into a Double-Track Tunnel



WANG Lei, TAN Zhongsheng, LUO Jianjun, LI Yujie, LI Feilong, SHANG Suying

2024, 52(11):  141-150.  doi:10.12141/j.issn.1000-565X.230430

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Different operating environments under the action of crosswind lead to an abrupt change in the aerodynamic characteristics of high-speed trains (HSTs), which seriously affect the train operation safety and passenger comfort. Considering the compressibility and unsteady characteristics of flow field, a 3D numerical model including tunnel, HST and crosswind was established, and the SST k-w model was adopted to solve the problem. The accuracy of the numerical simulation was verified by comparing with the dynamic model test. It further analyzed the influence of cross wind on the flow field and surface pressure distribution around the train, and obtained the aerodynamic load change law of the train under the action of cross wind. The results show that the flow field distribution around the train is significantly affected by the crosswind. The flow field shifts to the leeward side of the train outside the tunnel, forming a longitudinal vortex starting from the tunnel entrance, while the vortex structures on the leeward side of the train disappear and form a vertical vortex at the extension entrance in the space on the windward side. Furthermore, the vortex structures in the tunnel disappear as the train enters. Before the train enters the tunnel, the aerodynamic pressure on the windward surfaces of the train is mainly positive, and the aerodynamic pressure on the leeward surfaces is mainly negative.The surface pressure of the train changes most obviously when the train enters the tunnel, and the fluctuation degree of the aerodynamic pressure decreases obviously with the train entering the tunnel. The variation of aerodynamic load is closely related to the wind environment. The side force and lift amplitude of the rear vehicle (RV) are the largest when there is non-crosswind, and the side force and lift amplitude of the head vehicle (HV) are the largest when there is crosswind. In addition, the aerodynamic performance is closely related to the marshaling position. The variation amplitudes of the side force of the HV are 4.8 and 15.4 times of that of the RV, respectively. The variation amplitudes of the lift of HV are 1.1 and 1.2 times of that of RV, respectively. And the risk of traveling safety accidents of the HV is the highest. The research results can provide a reference for the safety evaluation of HST and route selection of high-speed railway tunnels.