Objective The car body of metro vehicle is a welded structure, and its fatigue strength is obviously smaller than that of the base metal due to the influence of stress concentration, welding defects and welding residual stress. As the part connecting bogie and car body, the end underframe of metro vehicle bears more load.Therefore, it is necessary to study its fatigue life. Method The numerical simulation and fatigue test are jointly used to study the fatigue life of the end underframe of a certain type of metro train. Firstly, a finite element model of metro vehicle is established and the corresponding fatigue load and evaluation points are determined.Then, the fatigue damage simulation is carried out on the whole train and the end underframe respectively. Finally,the bench test on the end underframe is performed, and the result is compared with that of the train fatigue test and the simulation result of the end underframe. Result & Conclusion Under the condition of unidirectional fatigue damage and combined load fatigue damage, both the vehicle chassis (underframe) and the end underframe of the metro train car body have no risk of cracking, meeting the requirements of the relevant standards. Meanwhile, the end underframe can obtain more conservative results in fatigue test when the load is amplified, and the simulation results of the end underframe finite element model are in good agreement with its test results, which can truly reflect the stress state of the train model and meet the requirements of the relevant standards.

针对某悬挂式单轨车辆,采用HyperMesh进行了有限元建模,采用Optistruct软件依据EN 12663-1:2010+A1:2014标准P-V等级的要求对悬挂式单轨车辆车体结构的静强度、疲劳强度、白车身模态和整备模态进行了有限元计算和评估.计算结果表明:各个静强度工况下,该悬挂式单轨车体结构的vonMises应力均小于材料的屈服强度;各个疲劳工况下,该悬挂式单轨车体结构焊缝的疲劳应力范围均小于BS EN 1999-1-3 Eurocode 9标准规定的疲劳极限;白车身和整备状态下的车体一阶垂弯频率均大于10Hz.该悬挂式单轨车体结构静强度、疲劳强度和模态满足设计要求.

地铁车辆结构形式和功能配置的多样化,给地铁列车互联互通带来一定困难.针对目前我国地铁车辆技术规格书要求的多样性开展调研分析.根据调研结果,修改完善当前地铁车辆技术条件,编制系列化中国标准地铁列车4种车型技术规格书.分析技术规格书中车体技术条件与既有地铁列车执行标准及规范的主要差异,为标准化地铁列车研制项目技术创新成果的推广提供参考.

针对某不锈钢地铁车体结构,采用BS 7608、Eurocode3和IIW标准分别对焊缝进行了疲劳寿命评估,结果表明Eurocode 3和IIW的评估结果要严于BS 7608的结果.

为提升城轨客车车体整体性能和平整度,研究城轨客车激光焊不锈钢侧墙制造技术.介绍激光焊焊接设备,设计激光焊侧墙结构,阐述激光焊侧墙单元制备流程.经过焊接接头疲劳试验、侧墙单元疲劳试验、车体仿真分析及静强度试验等,验证不锈钢激光焊侧墙能够满足各项技术指标,可用于不锈钢城轨客车车体.

为了研究地铁车辆枕梁服役安全性问题,考虑到大量疲劳实验耗时长且成本高,利用虚拟实验方法对枕梁结构疲劳寿命进行评估,根据EN12663-1标准设计枕梁静力实验,获得枕梁表面特征点的应力值和位移值;然后对枕梁进行有限元建模并仿真,对比静力实验结果,调整后获得与枕梁实际结构相符的有限元模型;最后利用Monte Carlo方法,进行地铁车辆枕梁在恒幅载荷与变幅载荷作用下的虚拟疲劳实验.研究结果表明:在标准规定的恒幅载荷作用下,该地铁车辆枕梁寿命大于1 000万次载荷循环的可靠度约为0.73;在变幅载荷作用下,寿命大于1 000万次载荷作用的可靠度约为0.81;因此,该地铁车辆枕梁完全满足设计与使用要求.

The bolster is a key structure for the metro train. To evaluate its fatigue reliability under the fatigue loading scheme, the full-scale fatigue test and theoretical calculation are performed. The bolster is modeled as a series system of stress concentration zones, namely weak points, and their stresses are calculated using validated finite element method (FEM). Since no fatigue crack is observed after the test and the fatigue life predicted by the Goodman diagram is more than [Formula: see text] load cycles, the bolster can service for more than 30 years with 90% reliability. To learn more about its fatigue reliability during the real service, a fatigue reliability model is established based on stress-life interference model. 10 load spectra are generated by Poisson processes, and the bolster is also modelled as a series system of six weak points. As a result, its cumulative failure probability is less than 0.002% within its 30-year service under normal atmospheric conditions.

车钩作为地铁车辆的重要组成部分,主要包括钩头、缓冲器、压溃管和过载保护装置等,具有连接轨道车辆、传递及缓和列车间栽荷、吸收碰撞能量的作用,文章介绍了车钩主要部件的工作原理,阐述了各部件的设计选择依据.

Plasma-MAG hybrid welding method and ordinary MAG welding method were used respectively to carry out the welding tests of SUS301L-MT stainless steel middle heavy plates for railway vehicles under the condition of ER308LSi welding wire and ψ (Ar)98％+ψ(CO2)2％ shield gas selected.The pulsating tensile fatigue test and the fatigue strength estimation were conducted on the butt welded joints and the cruciform joints of plasma-MAG hybrid welding and ordinary MAG welding respectively.The results indicate that the median fatigue strength in fatigue life of 2×106 cycle is 279 MPa and 160 MPa for the butt joint and the cruciform joint of plasma-MAG hybrid welding respectively.Compared with ordinary MAG welding,the fatigue strength of plasma-MAG hybrid welded joints increases,in which the fatigue strength of butt joint is higher than that of cruciform joint.

The structural safety of a subway bolster is studied by fatigue strength testing and numerical simulation. A novel approach is proposed to determine the loading scheme in the fatigue test. This method identifies the loads accurately and allows for efficient yet economical fatigue test. Full-scale fatigue test of the bolster is carried out up to 1 × 10 7 load cycles under normal atmospheric conditions. The finite element model is validated based on the stresses measured by strain gauges. The fatigue life of the bolster is evaluated by Goodman diagram and nondestructive test since it is modeled as a series system of weak points. The results demonstrate that this bolster satisfies the structural safety requirement and its fatigue life is more than 1 × 10 7 load cycles with 90% reliability.

介绍了一种新型地铁车辆碰撞吸能结构,各吸能模块的结构及吸能原理.按EN15227:2008中C-I类车辆碰撞要求对吸能结构进行有限元仿真分析

通过对车载空调激励对车体振动贡献的分析,研究了某地铁车辆车载空调和空压机激励状态对乘坐舒适度的影响.结果表明:①空压机运行状态对车辆两端的舒适度指标几乎无影响,车辆中部的舒适度指标受空压机运行影响较大,空调状态对舒适度影响很小;②车辆的舒适度指标随速度的提高而线性增加.同样速度级别下,1位端的舒适度指标最大,中部的舒适度指标最小;③设备对舒适度的贡献率γ2随车速提高而下降,线路对舒适度的贡献率γ1随车速提高而上升,当γ1=γ2时的车速为临界速度VCR·对于车辆1位端来说VCR=25 km/h,对于车辆2位端来说VCR=35 km/h,车辆中部在试验速度范围内无临界速度.

The design thought of the energy absorption in collision of metro cars is described.The design principle and basis for selection of vairousgrades of energy absorption elements are expounded.

As the impact process of train energy absorbing components occurs in a short time, high-speed cameras are used to record it and the amount of deformation and energy change of the energy absorbing components can be obtained by analyzing sequential images. The method of sequential images analysis presented is based on feature recognition of mark points by template matching method. In addition to this, error introduced by the camera positions is corrected to obtain more exact results. During the process of collision, the amount of its deformation is 52mm and its energy change is 2.69KJ when using the sequential image analysis.

The laser welded joint and metal active gas ARE welding(MAG)joint residual stress of SUS301L austenitic stainless steel for subway were studied by X-ray diffraction analysis.The results show that there are larger tensile stress and the residual stress distribution are the same trend in the laser welding and MAG welding joint.The reasons for the maximum welding residual stress in the laser welding joint is lower than MAG welded joint is that the laser welding heat input is smaller,the thermal compression effect of base metal is lower and the base metal plastic compression effect is lower.

对客车车下柴油发电机组吊座结构进行分析和有限元强度计算,依据计算结果对原有结构进行了补强,保证机组吊座的强度和客车运行的安全性.