超重型车组的选型与设计

目前，公路大件运输的超重型车组大多都使用大功率牵引车和液压平板挂车进行组合。 1超重型车组的组合方式 组合方式一般有三种：半挂式牵引、全挂式牵引和变型牵引。     

汽车挂车的选型与设计(二)

二、挂车车型的分类及选择牵引汽车(载货牵引车、压重牵引车、鞍式牵引车)和挂车(包括全挂和半挂车)组成汽车列车,其挂车根据不同的运输对象和要求有多种型式,按其牵引方式和结构特点大致可分为:     

地下空间结构预制拼装技术综述

随着城市建设的发展,如何解决地下工程建设中的速度、质量、效益问题成为人们关注的焦点。地下空间结构采用预制拼装技术是提高工程质量、缩短工期、节省造价的有效方法。在论述地下预制拼装特点及发展趋势的基础上,介绍盾构圆形隧道预制拼装式衬砌结构、明挖法公路和铁路隧道拼装结构、明挖地铁车站预制拼装结构、明挖综合管沟预制拼装结构和微型地下智能停车库预制拼装结构等几种主要地下预制拼装结构,以供类似工程参考借鉴。     

双轴转向挂车性能参数确定

双轴转向挂车具有转向半径小、机动灵活的特点，适合于场地狭窄情况的运输要求。介绍了一种双轴转向挂车的结构型式，并分析了不同方案的结构特点。通过双轴转向挂车列车转向过程的几何分析，导出了转弯半径、相邻两挂车铰接点的位置以及牵引杆的长度计算公式     

隧道大口径内衬钢瓦片运调一体机优化设计

外界环境或者施工质量缺陷造成输水管线中预制混凝土管片裂纹或者坍塌,需运输大口径内衬钢瓦片进行加固。针对隧道内大口径内衬钢瓦片与隧道壁间隙小、长距离运输的钢瓦片为偏心结构和拼装对接精度要求高等施工技术难题,设计制造内衬钢瓦片运调一体机。针对钢瓦片的夹持机构、运输纠偏和拼装对接等关键功能进行结构优化设计和系统分析,并根据钢瓦片结构特征和施工环境确定钢瓦片的最佳夹持、运输和拼装对接方式,同时采用有限元分析方法对内衬钢瓦片运调一体机整体结构进行强度校核。实际工程应用表明： 1)内衬钢瓦片运调一体机结构设计合理,强度稳定性和设备功能满足现场施工要求,为大口径内衬钢瓦片在隧道内长距离运输和拼装对接施工提供了一种技术方案; 2）提高了内衬钢瓦片在隧道内的运输效率和拼装对接精度,并降低了施工难度和施工成本。     

东南亚全开门厢式运输理念移植中国的可行性探讨

正随着道路交通法规要求的越来越严,以及环境保护要求的越来越高,货物散装裸露运输逐步被禁止。欧、美、日、澳等经济与物流发达国家和地区,较早实现了普通货物厢式封闭标准高效运输,各类厢式货车成了道路货物运输的主流车型;甚至东南亚部分国家(如泰国)也较早推广了厢式运输,并推行了一种装卸效率很高的全开门厢式货车(单车、半挂车、全挂车等)。相比之下,中国虽然提倡和推行厢式运输已经多年,但其厢式运输车的结构形式仍显得较为拘谨,甚至落后,达不到高     

克诺尔商用车制动系统技术发展(四)

“TEBS是克诺尔以长期从事电子制动系统和气制动系统开发和生产的经验为基础,针对挂车的要求开发的。⑤该系统采用模块结构可适应各种驱动形式的汽车(2)克诺尔开发的挂车电子制动系统(TEBS) TEBS是克诺尔以长期从事电子制动系统和气制动系统开发和生产的经验为基础,针对挂车的要求开发的,主要用于     

切勿擅自改动挂车原厂制动配置

<正>在人工成本不断增高的情况下,自动调整臂不需要像手调臂一样人为地定期调整,减少了维修次数,延长车辆保养的间隔时间,从而增加经济效益。随着我国高速公路网的不断完善,长途物流运输越来越多地使用主挂车连接的运输方式,而且趋向于集成化、大吨位,这就对主挂车制动系统的匹配、协调及可靠性提出了更高要求。本文通过梳理我国目前主挂车制动系统在使用中出现的问题,提出相应的解决方案。主挂车制动系统存在的问题及原因目前我国主挂车运输车辆的驱动     

散装水泥运输罐车刹车过程物料流动特性研究

为探索散装水泥运输半挂车在刹车过程罐内物料的流动特性，基于FLUENT计算流体力学软件，采用欧拉-欧拉方法建立双流体模型，通过Syamlal-O＇Brien模型描述气-固曳力，对散装水泥运输半挂车在刹车过程罐内水泥的流动特性进行了数值模拟。结果表明，散装水泥运输半挂车在刹车过程中，罐内水泥向前运动，牵引车载荷高于设计载荷，对此提出通过在罐内顶部增设阻流板，可有效避免散装水泥运输半挂车在刹车过程由于载荷分布不合理而引起的一系列问题的改进措施。     

拼装式双柱桥墩抗震能力的评估

采用三线型滞回模型，对拼装式双柱桥墩进行了弹塑性地震反应分析，并分别对常遇小震、中震及罕遇大震时的抗震能力进行了评估。计算结果表明，现有定型设计的拼装式双柱桥墩，能满足在设计烈度为７￣９度地震区“小震不坏”、“中震可修”，以及在７￣８度地震区“大震不倒”的设计要求。     

机场拖车制动系统的改进方案探析

以现有的机场拖车为原型,针对制动时存在的问题,提出了一些改进建议和想法,使拖车在牵引车制动时能利用自身的惯性力自行制动,减少制动距离和时间,以符合当前机场大运货量对制动距离的要求。     

Lateral dynamics of motorcycles towing single-wheeled trailers

A motorcycle towing a single-wheel trailer may provide useful transport for light cargo on narrow tracks and off-road use, particularly in rural areas of developing countries. Four designs of such trailers are described. Linear models are derived for the lateral dynamics of an off-road motorcycle towing this type of trailer straight ahead at constant speed. The trailers were tested behind an instrumented motorcycle. Linear autoregressive models were fitted to the experimental data using system identification techniques. Analytical and experimentally derived models largely agreed on frequency, damping and shape of the weave, wobble and trailer sway normal modes. The trailers made the motorcycle’s steering heavier but the analytical models did not predict this. The location of the articulation axes between the motorcycle and the trailer were found to be critical for stability. The best trailer design handled well with loads up to 200 kg and speeds up to 70 km/h.     

Lateral dynamics of motorcycles towing single-wheeled trailers

A motorcycle towing a single-wheel trailer may provide useful transport for light cargo on narrow tracks and off-road use, particularly in rural areas of developing countries. Four designs of such trailers are described. Linear models are derived for the lateral dynamics of an off-road motorcycle towing this type of trailer straight ahead at constant speed. The trailers were tested behind an instrumented motorcycle. Linear autoregressive models were fitted to the experimental data using system identification techniques. Analytical and experimentally derived models largely agreed on frequency, damping and shape of the weave, wobble and trailer sway normal modes. The trailers made the motorcycle's steering heavier but the analytical models did not predict this. The location of the articulation axes between the motorcycle and the trailer were found to be critical for stability. The best trailer design handled well with loads up to 200 kg and speeds up to 70 km/h.     

Stabilization of Passenger Car-Caravan Combination Using Four Wheel Steering Control

This study aims to stabilize the trailer at high speed. The behavior of passenger cars with four wheel steering system, vehicles with rear wheel steering and of trailer and passenger car are similar. This is regarded as an optimal regulator problem with linear equation of motion, and a state variables feedback control system is adopted. The problem of stability at high speed on a straight course can be solved. Therefore, the passenger car-trailer system can be stabilized. Furthermore, this study indicates the way forward to stabilize a passenger car-trailer system.     

全挂汽车列车制动防抱死系统的协调控制

以某型全挂汽车列车为研究对象,分别安装牵引车及挂车两套制动防抱死系统,并建立相关协调模块使两套系统协调工作。运用Matlab/Simulink软件对未安装及安装ABS系统的全挂汽车列车在高附着系数路面上进行直线制动仿真。分析对比仿真结果,证明协调模块使得两套ABS系统顺利工作,挂车与牵引车制动强度相协调,显著提高了列车制动稳定性。     

470 t大件通过珞璜电厂桥方案的设计与实践

重庆珞璜电厂三期工程需运输自重397t、车货总重470t的50万kW发电机组的变压器通过2座简支T形梁桥，原桥能力远远不能满足大件通过的需要。通常情况超过桥梁设计荷载标准的重载车过桥是采用对桥梁进行加固的方法，而对超过承载力数倍的简支T形梁桥不仅加固难度大，且既费钱又费时。提出了一种利用原桥墩、台架设临时铜便桥与原桥组合受力共同承担大件通过的运输方案。通过结构设计计算和470t大件通过珞璜2座桥梁的实践，证明该方法是解决重点建设工程大型设备运输的不仅省钱、省时，而且安全可靠的好方法，为今后大件运输提供了一条新途经：     

通用轻型全挂车底盘设计

介绍了一种通用轻型全挂车底盘,通过采用全新设计元素,提高了全挂车的通用性和可操作性,解决了普通全挂车存在的牵引机构难调节、减震效果差、倒车难解除制动等问题,具有广阔的应用前景。     

全挂车底盘制动系统故障树分析

采用故障树分析法对全挂车底盘制动系统进行了分析，计算了制动系统的失效率，并分析了影响制动系统失效的主要因素，提出了相应的改进建议。     

铰接车辆电涡流缓速器联合制动系统研究

提出利用联合制动系统将电涡流缓速器应用到铰接车辆上的方法。联合制动系统由拖车上的电涡流缓速器和挂车电控制动系统组成,二者在ECU控制下可以保证拖车与挂车制动力的合理分配以及对拖车及挂车的制动实施时间进行干预。采用该系统还可以减少铰接车辆行驶中某些事故的发生。     

Longitudinal Oscillations of Vehicle/Trailer Combinations Induced by Overrun Braking

A mathematical model for the representation of longitudinal oscillations which can occur in car/trailer systems in braking, when the trailer brakes are applied through compression of the towing hitch, is described. The model is used to show how the trailer braking system parameters affect the steady deceleration performance of the vehicle combination, and the stability, in the linear system sense, of the steady motions. The sensitivity of the stability to other system design parameters is also examined.

Digital simulation of the motions occurring in response to a step input of car braking torque is reported, with the results confirming the predictions of the linear stability analysis, and also showing the influence of backlash in the trailer brake actuating mechanism.

The system is shown to be capable of self-excitation in a “shunting” mode, in which the car and trailer motions are in antiphase, with the stability/damping property critically dependent on drawbar damping, and only weakly dependent on other system parameters. The characteristic frequency of the “shunting” mode oscillations is shown to be controllable via the stiffness of the trailer brake linkage, but this frequency is closely related to the steady drawbar deflection which occurs in uniform deceleration.

The model behaviour described provides a basis for the design of relevant systems whose longitudinal dynamic characteristics will be satisfactory.