重载铁路隧道设计技术探讨

为解决重载运输条件下铁路隧道设计难题,通过大秦线铁路隧道病害的调查资料,对重载运输诱发的隧道病害及其原因进行总结分析。依托山西中南部铁路通道隧道设计经验,提出重载铁路：〖JP〗 1）软弱破碎围岩大于1000m或软岩高地应力段长大于500m的隧道、4km以上突水突泥风险等级较高的岩溶隧道优选采用2个单线隧道方案; 2）单线隧道仰拱矢跨比取1/6.5、双线取1/10.5,可以满足30t列车轴质量要求; 3)隧道内坡度不应小于3‰、富水地层不小于5‰,提出防排水措施实现运营可维护; 4)计算确定了轨下结构设计参数; 5)对隧道内轨道结构过渡、轨下及隧底结构过渡段采取了设计措施; 6)提出了隧道基底普查及承载要求。     

高尧Ⅰ号大桥连续刚构三种挂篮主桁的设计分析

通过高尧Ⅰ号大桥连续刚构的挂篮设计,采用Midas对三种(菱形、三角形、弓弦式)主桁结构进行分析和比较,一方面了解不同主桁形式的力学特点,另一方面可作挂篮设计和选用时的参考。     

An inverse railway wagon model and its applications

An inverse wagon model was developed to estimate wheel-rail contact forces using only measurements of wagon body responses as inputs. The purpose of this work was to provide mathematical modelling to embed in low-cost devices that can be mounted on each freight wagon in a large wagon fleet. To minimize cost, complication, and the maintenance inconvenience of these devices, the constraint is imposed that transducers and connections are limited to locations on the wagon body. Inputs to the inverse model developed include only vertical and lateral translational accelerations and angular accelerations of roll, pitch, and yaw of the wagon body. The model combines the integration and partial modal matrix (PMM) techniques together to form an IPMM method. Besides wheel-rail contact forces some motion quantities such as the lateral and yaw displacements of wheelset are also predicted. Results from the inverse model were compared with data from full scale laboratory suspension tests for vertical suspension excitations. The inverse model was also compared with results from simulations completed in VAMPIRE^® for more complicated track input profiles. The model results and the applications of the model are discussed.     

五河口预应力混凝土斜拉桥主梁的设计与施工

简要介绍了五河口预应力混凝土斜拉桥双边箱主梁的设计与施工。由于跨径大、桥面宽,设计和施工中碰到很多问题,本桥对这些问题的处理方法,可为今后类似的预应力混凝土斜拉桥的建设提供参考。     

Longitudinal train dynamics: an overview

This paper discusses the evolution of longitudinal train dynamics (LTD) simulations, which covers numerical solvers, vehicle connection systems, air brake systems, wagon dumper systems and locomotives, resistance forces and gravitational components, vehicle in-train instabilities, and computing schemes. A number of potential research topics are suggested, such as modelling of friction, polymer, and transition characteristics for vehicle connection simulations, studies of wagon dumping operations, proper modelling of vehicle in-train instabilities, and computing schemes for LTD simulations. Evidence shows that LTD simulations have evolved with computing capabilities. Currently, advanced component models that directly describe the working principles of the operation of air brake systems, vehicle connection systems, and traction systems are available. Parallel computing is a good solution to combine and simulate all these advanced models. Parallel computing can also be used to conduct three-dimensional long train dynamics simulations.     

铁路空车调整的算法模型及软件实现

本文结合我国铁路空车调整计划的实际,提出了空车调整的优化算法,探讨了人工智能在此问题上的应用,并针对当前常用的B/S软件结构给出了具体的软件实现.     

混沌蚁群算法在空车调整问题中的应用

根据空车车流的混沌特性,以空车走行公里数最少为优化目标,提出了采用混沌蚁群算法求解空车调整问题.通过算例求解,验证了采用混沌蚁群算法求解空车调整问题的合理性和有效性.     

环境风对路堤上快运集装箱平车气动力性能影响

基于三维、定常、不可压Navier-Stokes方程和k-epsilon双方程湍流模型,采用FLUENT流场计算软件对环境风作用下铁路快运集装箱专用平车(简称集装箱平车)所受气动力进行数值模拟计算。分析列车在铁路路堤上运行时车速和风速对车辆气动性能的影响,得出车辆气动力与车速、风速之间的变化关系。研究结果表明,在环境风作用下,10 m路堤上运行的集装箱平车:1)迎风面处于较大的正压区内,背风面处于负压区内,集装箱平车的背风面、顶部以及底架附近,均有漩涡产生;2)风速为32 m/s、风向角为90°时,车辆所受横向力、升力和倾覆力矩均随着车速的增大而增大;3)车速为160 km/h、风向角为90°时,车辆所受横向力、升力和倾覆力矩随风速的增大而增大;其中倾覆力矩近似与风速的1.6次方成正比。     

铁路车站空车调配优化模型设计

空车调配是铁路车站运输组织工作的重要内容。参考传统运输问题模型,结合车种代用、分阶段实施、重点任务优先完成、摘挂作业机车消耗等实际问题,首先提出车站空车调配的确定性数学模型,然后考虑车流推算数据与实际生产之间的误差,综合目标函数与作业点空车供应量的不确定性,建立车站空车调配的模糊规划模型,提出模型求解的思路与方法。     

瞬态冲击响应的数值技术及其在120t平车设计中的应用

１２０ｔ钢锭运输平车经常承受突然的冲击载荷。在讨论了基于振型迭加法的瞬态冲击响应的关键技术之后,用Ｉ－ＤＥＡＳ软件对１２０ｔ平车钢结构进行了瞬态冲击响应计算,其计算结果对设计十分重要。