桥梁附加变形对高速列车运行安全影响的研究

发布时间：2018-04-16 12:05

本文选题：高速列车 + 软土地基　；参考：《北京交通大学》2015年博士论文

【摘要】：修筑于软土地基的高速铁路混凝土桥梁投入运营以后,受列车循环加载及混凝土徐变特性的影响,桥梁会发生基础不均匀沉降及梁体变形,从而引起桥上轨道结构的附加变形,影响桥上列车的运行安全。本文在国家重点基础研究发展计划“973”项目“基础结构性能演变对高速行车安全平稳性的影响及其控制研究(2013CB036203)”的资助下,研究了由桥梁基础沉降及混凝土徐变引起的桥上轨道结构动态演变规律及其对桥上高速列车运行性能的影响。主要研究内容及成果如下： (1)综述了世界高速铁路发展现状,说明了研究桥上线路条件恶化对列车运行安全性影响的必要性；简述了国内外车辆-桥梁系统动力问题的主要研究内容及方法；总结了软土地基附加沉降和混凝土桥梁徐变等引起的附加变形及车体柔性对车辆-桥梁系统动力响应影响的研究现状,说明了本文的选题意义及立项依据。 (2)推导了简支梁在移动恒定荷载及移动简谐荷载作用下位移响应的精确解,并通过引入三个无量纲参数,分析了荷载移动速度、桥梁阻尼、简谐荷载的荷载频率及荷载间距等因素对桥梁动力响应的影响规律,研究了简支梁在单个及多个移动荷载作用下的共振及消振现象。 (3)假定车体为等截面欧拉梁,建立了柔性车体车辆模型,将车体位移用刚体位移及自由边界欧拉梁振型表示,推导了柔性车体的运动方程,进而得到了车辆模型的运动方程。利用改进的Penzien模型建立了能够考虑桩-土相互作用的桥梁子模型,并给出了土弹簧刚度的求解方程。基于车辆子模型和桥梁子模型建立了柔性车体车辆-桥梁耦合系统动力分析模型。 (4)基于理论推导和数值计算,对比研究了柔性/刚性车体车辆-桥梁系统在轨道不平顺激励下的动力响应,给出了柔性/刚性车体车辆模型在不同波长简谐不平顺激励下轮重减载率、横向轮轨力和车体加速度等指标的响应规律,分析了柔性车体在某些列车速度和不平顺波长组合下的共振现象。 (5)基于黄茂松等人提出的循环荷载作用下软土累积变形及累积孔压计算模型,研究了利用分层总合法求解列车循环荷载作用下桥梁基础附加沉降的实用计算方法。以德国ICE3高速列车通过一座高速铁路(48+80+48)m三跨预应力混凝土连续梁桥为例,研究了列车循环荷载作用下桥梁基础的附加沉降规律,及沉降引起的桥上轨道附加变形的线型特点及频谱特性。利用柔性/刚性车体车辆模型对比研究了桥梁基础附加沉降对桥上列车走行性的影响规律。通过假定随机不平顺激励下车辆各项运行指标计算值符合正态分布,给出了不同列车速度及桥梁基础附加沉降工况下置信度为95%的列车运行安全性与舒适性阂值。 (6)以高速铁路线上跨径32m和24m多跨简支梁和CRTSIII型无砟轨道结构为例,利用有限元软件MIDAS/CIVIL研究了养护时间和铺轨时间等施工条件对简支梁徐变的影响规律及由徐变引起的附加扣件力沿梁体的分布特性,分析了梁体徐变引起的桥上轨道附加变形的线型特点及频谱特性。以德国ICE3高速列车通过10×32m和10×24m简支梁桥为例,利用柔性/刚性车体车辆-桥梁系统动力分析模型对比分析了梁体徐变对桥上列车走行性的影响规律。通过假定随机不平顺激励下车辆各项运行指标计算值符合正态分布,给出了不同列车速度及梁体徐变工况下的置信度为95%的列车运行安全性与舒适性阈值。
[Abstract]:After the high-speed railway concrete bridge construction in soft soil foundation is put into operation, affected by the train cyclic loading and concrete creep, the bridge will occur uneven foundation settlement and deformation of the girder, causing additional deformation of track structure on bridge, affecting the safety of train running on the bridge. Based on the study of the evolution of infrastructure performance on the stability of the safety of high-speed driving and control of the national key basic research program of the "973" project "(2013CB036203)" supported by the study of the dynamic track structure caused by bridge foundation settlement and creep of concrete on the bridge on the bridge on the evolution and performance of high-speed train. The main research contents and results are as follows:
(1) the current situation of the development of high-speed railway in the world were reviewed, illustrates the necessity of the deterioration of the security of the train line of the bridge; the main research contents and methods at home and abroad were introduced vehicle bridge system dynamic problems; summarizes the soft soil foundation settlement and concrete bridge creep caused by additional deformation flexible body current research on vehicle bridge dynamic response system, illustrate the significance of the topic and project basis.
(2) the exact solution is derived in the mobile beam shift response constant load and moving harmonic load lower, and by introducing three dimensionless parameters, analyzed the load speed, bridge damping, harmonic load load and load frequency spacing and other factors on the influence of the dynamic response of the bridge, the research on single beam resonance and a plurality of moving loads and vibration phenomenon.
(3) assumed body uniform Euler beam, a flexible body vehicle model with rigid displacement and free boundary displacement Euler beam vibration body, motion equations of the flexible body is derived, and then obtain the equations of motion of the vehicle model was established. The bridge sub model considering pile soil interaction by Penzien the improved model, and solving the equation of soil spring stiffness is given. Liangzi model of vehicle sub model and established the bridge dynamic analysis model of flexible body vehicle bridge coupling system based on.
(4) theoretically and calculated numerically based on the comparative study of the flexible / rigid body vehicle bridge system in the track irregularity dynamic response, given flexible / rigid body vehicle model in different wavelength harmonic irregularity excitation of wheel load reduction rate, response of wheel rail lateral force and vehicle acceleration indicators. Analysis of flexible body in some train speed and irregularity wavelength combination resonance phenomenon.
(5) soft soil cyclic loading is proposed by Huang Maosong et al the accumulative deformation and pore pressure calculation model based on the calculation method of practical settlement of bridge foundation using hierarchical method for solving train under cyclic loading. In Germany ICE3 high-speed train through a high speed railway (48+80+48) m three span prestressed concrete continuous bridge as an example, the additional settlement regularity of bridge foundation under cyclic loading of the train, the linear characteristics and frequency spectrum characteristics and settlement caused by track additional deformation. Using flexible / rigid body vehicle model to study the bridge foundation settlement than the influence of line train on the bridge. By assuming random walk irregularity excitation vehicle the operation index calculated with normal distribution, given different train speed and bridge foundation settlement under the condition of confidence of 95% train transport For the safety and comfort of the threshold value.
(6) to high speed railway line span 32m and 24m multi span beam and CRTSIII type ballastless track structure as an example, the distribution characteristics of the construction conditions of the curing time and laying time of beams caused by creep and creep additional stress along the beam fastener using finite element software MIDAS/CIVIL, analyzes the characteristics of linear and the spectrum characteristics caused by concrete creep on the bridge rail. Additional deformation in Germany ICE3 high-speed train by 10 * 32m and 10 * 24m bridge as an example, analysis model of comparative analysis of concrete creep on the moving train on bridge of influence using flexible / rigid body vehicle bridge system by assuming power. The random irregularity excitation of the vehicle the operation index calculated with normal distribution, given different train speed and beam creep under the condition of the confidence level of 95% train safety and comfort threshold.

【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：U298;U441

【参考文献】