考虑速度锁定器的重载铁路桥梁纵向动力问题研究

发布时间：2018-05-11 19:45

本文选题：重载铁路 + 制动力　；参考：《北京交通大学》2014年硕士论文

【摘要】：近年来,重载铁路因其运能大、效率高、运输成本低而得到飞速发展,但是我国现有铁路桥梁设计规范中设计荷载偏低,不适应重载铁路大轴重的要求。铁路桥梁承受的各种载荷中,作用于轨面的制动力与铁路活载的大小相关,列车轴重增加直接导致制动力的增加,有可能造成实际制动力超出设计荷载而引起桥梁下部结构损坏。重载铁路桥梁为连续布置的简支梁时,列车制动只有列车轮对所在梁跨的固定墩承担制动力,不能充分发挥桥梁的整体纵向承载性能。如安装速度锁定器,则一方面可在制动时将各梁跨纵向耦联,使全桥各墩共同承担制动力,达到改善桥梁受力状态的目的；另一方面又允许桥梁在发生温度变形时保持静定体系,不致产生温度附加力。本文主要讨论速度锁定器在铁路桥梁中的应用,从制列车动力的计算、车桥纵向耦合系统分析、速度锁定器应用的探讨三个方面入手,在参考国内外速度锁定器应用在公路桥成果的基础上,以朔黄铁路简支T型梁桥为工程背景,对考虑设置速度锁定器的重载铁路桥梁纵向动力问题进行研究,主要包括以下几个方面： (1)对列车轨道桥梁纵向动力相互作用的研究方法进行总结,介绍桥梁系统、车辆系统的建模方法,轮轨关系的模拟以及全过程迭代法的求解过程,并提出一种切合实际的列车制动力的计算方法。 (2)研究现状重载铁路桥梁在列车制动力作用下的响应及钢轨纵向应力、钢轨纵向位移、梁端纵向位移、支座纵向反力、墩顶纵向反力等控制指标,并分析了其随列车制动形式的变化规律。 (3)选取合理的单元模拟速度锁定器,结合速度锁定器的工作原理和荷载-速度曲线,建立了车-桥速-度锁定器耦合动力学模型,并针对工程实例探讨速度锁定器的参数选取方法,进而确定了其关键参数,分析了其作用效果。 (4)针对背景桥梁,提出并分析了桥上速度锁定器的布置方案,通过列车制动时关键指标的对比,确定最优的布置方案；推导了速度锁定器在卡死状态下温度应力的重分布公式,研究了该不利状况对桥梁承载性能的影响。
[Abstract]:In recent years, heavy haul railway has been developed rapidly because of its large capacity, high efficiency and low transportation cost. However, the design load of existing railway bridge design code in our country is on the low side, which can not meet the requirements of heavy axle load of heavy haul railway. Among all kinds of loads on railway bridges, the braking force acting on rail surface is related to the size of railway live load, and the increase of axle load of train directly leads to the increase of braking force. It may cause the actual braking force to exceed the design load and cause damage to the understructure of the bridge. When the heavy-haul railway bridge is a simply supported beam with continuous arrangement, the braking force of the train brake is only the fixed pier of the beam span of the train wheelset, which can not give full play to the overall longitudinal bearing capacity of the bridge. If the speed locking device is installed, on the one hand, each beam can be coupled with each other longitudinally when braking, so that all the piers of the whole bridge can bear the braking force together to improve the stress state of the bridge. On the other hand, it allows the bridge to maintain statically indeterminate system in case of temperature deformation, so as not to produce temperature additional force. This paper mainly discusses the application of speed locker in railway bridge, starting with the calculation of train power, the analysis of longitudinal coupling system of vehicle and bridge, and the application of speed locker. Based on the application of speed lockers in highway bridges at home and abroad, the longitudinal dynamic problems of heavy-duty railway bridges with speed lockers are studied based on the engineering background of simply supported T-beam bridges of Shuohuang Railway. It mainly includes the following aspects: 1) summarize the research method of longitudinal dynamic interaction of train track bridge, introduce the bridge system, vehicle system modeling method, wheel-rail relation simulation and the whole process iterative method solution process. A practical calculation method of train braking force is put forward. 2) study the response of heavy haul railway bridge under train braking force and control indexes such as rail longitudinal stress, rail longitudinal displacement, beam end longitudinal displacement, support longitudinal reaction force, pier top longitudinal reaction force, etc. The variation law of train braking mode is analyzed. The coupling dynamic model of vehicle-bridge speed-degree locker is established by selecting reasonable unit simulation speed locker and combining the working principle of speed locker and load-velocity curve. The method of selecting the parameters of the speed locker is discussed in view of the engineering example, and the key parameters are determined, and the effect of the speed locker is analyzed. (4) aiming at the background bridge, this paper puts forward and analyzes the arrangement scheme of the speed locker on the bridge, determines the optimal arrangement scheme by comparing the key indexes of the train braking, and deduces the formula for the redistribution of the temperature stress of the speed locker under the condition of clamping. The influence of this unfavorable condition on the bearing capacity of the bridge is studied.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.13;U441

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