Optimization of Technical Specifications for Center-of-Gravity Height of Heavy-Haul Freight Wagons during Lateral Passage through Turnout Diverging Routes
The current technical specifications for the center-of-gravity (COG) height of heavy-haul freight wagons during lateral passage through turnout diverging routes on China's railways remain anchored to speed-limit criteria established several decades ago - criteria that are increasingly misaligned with the operational demands of modern high-capacity freight networks. To bridge this gap, this study integrates experimentally measured wire rope tensile forces obtained from JHPY-type tension load cells to explicitly characterize the cargo-vehicle coupling interaction. A refined cargo-vehicle-turnout coupled dynamics model is then developed, incorporating cargo-induced vibration effects on system-level dynamic responses. This advancement enables more accurate assessment of lateral running safety for wagons with varying COG heights when traversing turnout diverging routes. Based on the model, a parametric sensitivity analysis is conducted across five critical factors: wagon type, track geometry and stiffness, cargo loading configuration, crosswind intensity, and operating speed. The most adverse combination of these parameters is identified, and a targeted simulation-based experimental scheme is formulated to evaluate the lateral passage safety of wagons negotiating the No. 9 single-slip turnout under diverse COG height conditions. Through simulation, the suggestions for optimizing the technical specifications of the turnout lateral passage speed limits of heavy-haul freight wagons are proposed when the COG height is under and above the limit respectively. Results show that: unrestricted turnout lateral passage speed is deemed safe for the COG height h ≤ 2 300 mm; for 2 300 < h ≤ 2 400 mm, 2 400 < h ≤ 2 600 mm, and 2 600 < h ≤ 3 000 mm, the recommended maximum lateral passage speeds are 25 km · h-1, 20 km · h-1, and 15 km · h-1, respectively. Relative to the existing regulation - which imposes a uniform 15 km · h-1 limit for all wagons with h > 2 000 mm - the proposed framework raises the unrestricted-COG threshold from 2 000 to 2 300 mm and refines the speed limits for cases exceeding the limit into different levels.
这项沿用的重车重心高度技术管理条件,尽管有效地确保了货车运行的安全性,但是该规定不仅远低于国外相关标准[4-5],而且严重滞后于我国线路条件、车辆性能明显改善的现状,使我国部分轻浮货物运输从货物装载源头就面临满载方案难以制定的问题,制约了我国现有铁路货运系统运输能力的发挥。尤其值得注意的是:从表1中可见,当重车重心超高时,无论超高多少,侧向过岔均限速15 km · h-1,这一标准是否科学、合理,值得进一步研究论证。
在得出重心高度限制高度hp的基础上,考虑到现场操作的可行性与方便性,将重车重心高度hj 按100 mm增幅增加,探索各种重车重心超高高度下铁路货车侧向过岔时对应限速。此时,将运行速度设置为5 km · h-1、其余参数设置不变,采用脱轨系数、轮重减载率、倾覆系数和轮轴横向力指标进行车辆侧向过岔运行安全性测试;若评估结果均为安全,则将运行速度增加5 km · h-1,进行下一轮安全性测试,直至此轮循环中某运行速度vk 条件下车辆运行安全性评估结果为不安全,或者运行速度达到30 km · h-1仍评估为安全,结束此轮循环,按如下方式确定重车重心高度(hj +100)mm下的侧向过岔限速vlim。
(1)若因为某运行速度vk 条件下车辆运行安全性评估结果为不安全,致使此轮循环结束,则重车重心高度(hj +100)mm下的侧向过岔限速vlim=vk-1。记录该重车重心高度条件下的侧向过岔限速,然后判断此时重车重心高度是否达到3 000 mm;若没有达到,则将重车重心高度继续增大100 mm,并将运行速度重置至5 km · h-1,进行新设置重车重心高度条件下的车辆运行安全性测试。
(2)若因为运行速度达到30 km · h-1车辆运行安全性仍评估安全使此轮循环结束,则重车重心高度(hj +100)mm下的侧向过岔限速vlim=30 km · h-1。同样记录该重车重心高度条件下的侧向过岔限速,然后判断此时重车重心高度是否达到3 000 mm;若没有达到,则将重车重心高度继续增大100 mm,并将运行速度重置至5 km · h-1,进行新设置重车重心高度条件下的车辆运行安全性测试。
National Railway Administration of the People’s Republic of China. TB/T 30004—2021 Technical Requirements for Railway Cargo Loading and Reinforcement [S]. Beijing: China Railway Publishing House, 2021. in Chinese )
[3]
中国铁路总公司.铁路货物装载加固规则[M].北京:中国铁道出版社,2015:4.
[4]
China Railway Corporation. General Rules Covering Loading and Reinforcement in Railway Freight Wagons [M]. Beijing: China Railway Publishing House, 2015: 4. in Chinese
[5]
中华人民共和国铁道部.货物装载加固规则[M].北京:人民铁道出版社,1961.
[6]
Ministry of Railways of the People’s Republic of China. General Rules for Cargo Loading and Reinforcement [M]. Beijing: People’s Railway Publishing House, 1961. in Chinese
[7]
Organization for Cooperation of Railways. OSJD Reference Book on Multimodal, Intermodal, Combined, and Piggyback Transport [R]. Warsaw: Organization for Cooperation of Railways, 2024.
[8]
International Union of Railways. UIC Loading Guidelines: Code of Practice for the Loading and Securing of Goods on Railway Wagons [R]. Paris: International Union of Railways, 2019.
[9]
Association of American Railroads. AAR Open Top Loading Rules Manual [R]. Washington D.C.: Association of American Railroads, 2017.
[10]
北京交通大学.货物列车提速后合理的重车重心限制高度的研究[R].北京:北京交通大学,2007.
[11]
Beijing Jiaotong University. Research on the Reasonable Restriction Gravity Center Height of General Loaded Wagon Following Freight Train Speed Enhancements [R]. Beijing: Beijing Jiaotong University, 2007. in Chinese
China Academy of Railway Sciences. Experimental Study on the Dynamic Behavior of Gravity Center Height and Lateral Displacement of General Loaded Wagon after Speed Increase (Main Line Report) [R]. Beijing: China Academy of Railway Sciences, 2011. in Chinese
PENGYongzhao, LANGMaoxiang, WANGQingxiao, et al. Influences of the Loading Conditions on the Vertical Stability of Freight Car Negotiating Small Radius Curved Rails [J]. China Railway Science, 2011, 32 (2): 97-103. in Chinese
WEIYuguang, WEIJunfeng, YUYuebin, et al. Research on the Maximum Reasonable Axle Load of New Coal Open-Top Wagon [J]. China Railway Science, 2014, 35 (3): 97-101. in Chinese
HANMei, WANGYanling, PANGLiang, et al. Gravity Center Height Limit of Loaded Wagon Based on Safety Criteria for Derailment Coefficient [J]. China Railway Science, 2007, 28 (4): 106-110. in Chinese
YANGNengpu, HANMei, CHENChao, et al. Gravity Center Height Limit of Loaded Wagon Based on Dynamic Nadal Limits [J]. Journal of the China Railway Society, 2016, 38 (2): 33-41. in Chinese
LANGMaoxiang, PENGYongzhao, LIUChunqi. Influence of Gravity Center Height on Running Safety of Loaded Double-Stack Container Car [J]. Journal of Traffic and Transportation Engineering, 2010, 10 (6): 41-47. in Chinese
[24]
PENGY, LANGM. Calculation of Height Limit of Gravity Center of Loaded Wagon Based on Vertical Dynamic Load Coefficient [C]// Proceedings 2011 International Conference on Transportation, Mechanical, and Electrical Engineering (TMEE). Changchun, China. New York: IEEE Press, 2012: 1321-1324.
[25]
LIUH, LIUZ, SHENM. Study on the Experiment of the Safety of C62BK-Wagon Loaded Running on Sharp Curves after Raising the Limited Height of Gravity Center [J]. Applied Mechanics and Materials, 2012, 178/179/180/181: 2824-2828.
LIUHui, LIUZuoyi. Experiment of the Safety of C62BK Wagon Loaded Running on Sharp Curves [J]. Journal of Transport Information and Safety, 2012, 30 (5): 102-105. in Chinese
[28]
陈超.铁路通用货车重车重心合理限制高度的研究[D].北京:北京交通大学,2011.
[29]
CHENChao. Study on Permitted Height of Gravity Center of Railway Loaded General Wagon [D]. Beijing: Beijing Jiaotong University, 2011. in Chinese
[30]
ZHANGD, CLARKED, PENGQ, et al. Effect of the Combined Centre of Gravity on the Running Safety of Freight Wagons [J]. Vehicle System Dynamics, 2019, 57 (9): 1271-1286.
[31]
ZHANGD, TANGY, SUNZ, et al. Optimizing the Location of Wagon Gravity Centre to Improve the Curving Performance [J]. Vehicle System Dynamics, 2022, 60 (5): 1627-1641.
[32]
ZHANGD, TANGY, PENGQ, et al. Effect of Mass Distribution on Curving Performance for a Loaded Wagon [J]. Nonlinear Dynamics, 2021, 104 (3): 2259-2273.
ZHANGDuo, TANGYinying, PENGQiyuan, et al. Effect of Combined Gravity Center Location on Curving Performance for a C70H Open-Top Wagon Fixed with Goods [J]. Journal of the China Railway Society, 2021, 43 (4): 15-24. in Chinese
YANGNengpu. Research on Safe Running Velocities of Railway General Wagon with Different Combined Gravity Center Heights of Loaded Car [D]. Beijing: Beijing Jiaotong University, 2018. in Chinese
YANGNengpu, ZHOUMiao, WANGWenkun, et al. Research on Height of Combined Gravity Center and Control Rules of Loaded Wagons Based on Cargo-Vehicle-Track Coupling Dynamics Model [J]. Journal of the China Railway Society, 2023, 45 (8): 36-46. in Chinese
[39]
YANGN P, FENGF, HUANGQ, et al. Optimized Design to Adverse Transportation Conditions for Railway Freight System [J]. Accident Analysis and Prevention, 2021, 154: 106091.
LIUWeizhen, QINHangyuan, LIUJinzhao, et al. A Diagnosis Method for Vehicle Shaking in High-Speed Turnout Area Based on Generalized Demodulation and SSA-SVM [J]. China Railway Science, 2024, 45 (3): 1-11. in Chinese
GAOYuan, SIDaolin, WANGShuguo, et al. Influence of Wheel-Rail Profile Evolution on Contact Geometric Relationship in Turnout [J]. China Railway Science, 2023, 44 (5): 169-179. in Chinese
JUXin. Study on the Stability of Railway Freight Cars Running through Turnout in the Side Direction after Raising the Limited Height of Gravity Center [D]. Beijing: Beijing Jiaotong University, 2010. in Chinese
HEJidong, LIUZuoyi, ZHURun. Stability of Railway Freight Cars Running through Turnout in the Side Direction [J]. Journal of Transport Information and Safety, 2012, 30 (5): 90-93. in Chinese
[48]
中国铁路总公司.铁路技术管理规程(普速铁路部分)[M].北京:中国铁道出版社,2014.
[49]
China Railway Corporation. Technical Management Rules and Regulations for Railways (General Speed Railway) [M]. Beijing: China Railway Publishing House, 2014. in Chinese
[50]
朱小杰.地震作用下考虑轮轨多点接触关系的车-轨系统振动分析[D].长沙:中南大学,2022.
[51]
ZHUXiaojie. Analysis of Vehicle-Track System Vibration Considering Wheel-Rail Multi-Point Contact under Earthquake [D]. Changsha: Central South University, 2022. in Chinese
CHENYu, ZHOUJiayi, SONGJuan, et al. Comparative Study on Non-Hertzian Rolling Contact Models Considering Yaw Angle [J]. Journal of the China Railway Society, 2024, 46 (6): 108-118. in Chinese
National Railway Administration of the People’s Republic of China. GB/T 5599—2019 Specification for Dynamic Performance Assessment and Testing Verification of Rolling Stock [S]. Beijing: Standards Press of China, 2019. in Chinese )
Institute of Standardization and Metrology of the Ministry of Railways of China. GB/T 5599—1985 Railway Vehicles - Specification for Evaluation the Dynamic Performance and Accreditation Test [S]. Beijing: Standards Press of China, 1985. in Chinese )
[58]
WENZ, LIX, LIUB, et al. A Comprehensive Evaluation Method for Plateau Freshwater Lakes: a Case in the Erhai Lake [J]. Ecosystem Health and Sustainability, 2021, 7 (1): 1993753.
CHENChao, YANGNengpu, HANMei. Railroad Freight Transportation Unfavorable Conditions Analysis Based on Orthogonal Experiment [J]. Journal of Chang’an University (Natural Science Edition), 2015, 35 (): 75-79. in Chinese
[61]
赵菲.超限超重货物办理站资质管理相关问题的研究[D].北京:北京交通大学,2010.
[62]
ZHAOFei. Study on Qualification and Management of Handing Station for out-of-Gauge and Overweight Goods [D]. Beijing: Beijing Jiaotong University, 2010. in Chinese
LIHao, ZHAOGuotang, SUNJialin. Simulation Research on Dynamic Characteristics of EMU Passing through No.9 Turnout [J]. China Railway Science, 2017, 38 (6): 30-36. in Chinese
[65]
中国国家铁路集团有限公司.中国铁道年鉴-2022[M].北京:中国铁道出版社有限公司,2023.
[66]
China State Railway Group Co., Ltd. China Railway Yearbook-2022 [M]. Beijing: China Railway Publishing House Co., Ltd., 2023. in Chinese