RPC混凝土在铁路预应力T形梁中的应用试验

我国在迁曹铁路滦柏干渠大桥工程中，首次采用活性粉末混凝土（Reactive Powder Concrete，RPC）制作多孔预应力简支T形梁进行力学性能测试和行车监测，其中1孔（2片）进行了力学性能测试，5孔（10片）进行了行车监测，取得了良好的效果。通过RPC混凝土桥梁的制作和试验，总结了部分制作经验，通过力学性能测度，证明了RPC混凝土在铁路桥梁应用中的可行性和良好前景。     

The handling surface: a new perspective in vehicle dynamics

The problem of describing the understeer–oversteer behaviour of a general vehicle, such as one with locked differential or tandem rear axle, is addressed taking a new perspective. The well-known handling diagram and the associated classical understeer gradient may be inadequate, mainly because they are no longer unique. The new concept of handling surface and a new definition of understeer gradient, which is indeed the gradient of the handling surface and hence a vector, are presented. It is also shown how the new concepts relate to and generalize the classical ones. Finally, a procedure for the experimental measure of the new understeer gradient is outlined.     

离心铸造法制作耐磨铝锅的力学模型分析

本文根据Al和Si质点在离心力场中分布不同，采用离心铸造法制作耐磨铝锅，探讨其组成相的在离心力场中的分布和Si质点在离心力作用下的移动规律，并建立相应的Si质点速度一时间t定性曲线。     

开口钢管桩承载力影响因素

根据钢管桩轴向受荷承载力机理,从钢管桩的桩土特性、入岩深度、桩土恢复系数及沉桩工艺方面分析了开口钢管桩承载力的影响因素,提出在特定桩型、桩径情况下,桩的入岩深度及闭塞效应是影响桩承载力的重要因素,可通过改进沉桩工艺加深钢管桩入岩深度来提高桩承载力。     

波纹钢管加固不同破损程度混凝土管涵试验

为明确波纹钢管加固不同破损程度混凝土管涵的力学性能及机理，采用室内两点加载试验，对波纹钢管加固的未破坏、部分破坏和完全破坏的混凝土管涵进行研究，获得加固管的荷载-位移曲线、破坏特征和截面应变分布，基于破坏特征和截面应变分布假设加固系统为套管体系（Ⅱ类管），根据变形协调条件推导极限承载力的估算公式，并论述套管体系中各个管体的荷载分配机制。研究结果表明：波纹钢管不同程度地提高了混凝土管涵的承载能力和刚度；加固后的复合管为套管体系，荷载分配依据各个管体的环刚度大小，加固管极限承载力的计算值与实测值之间的误差小于10%；只要待加固的混凝土管涵未完全破坏，波纹钢管对钢筋混凝土管的加固效果相近，即部分破坏与未破坏的钢筋混凝土管涵采用波纹钢管加固后的承载能力相近，而完全破坏的钢筋混凝土管涵加固后的承载力较低；填充层不仅起到黏结作用，而且在荷载分配方面起着重要作用；当钢筋混凝土管涵从未破坏到完全破坏时，填充层所分担的荷载迅速增加（由30%增至80%），而波纹钢管分担的载荷仅略有增加（由7%增至18%）；当填充层的刚度从0增加到35 000 MPa时，填充层所分担的荷载从0增加到58%，钢筋混凝土管涵分担的荷载从69%下降到29%，波纹钢管分担的荷载由31%下降到13%。     

桥上列车脱轨的力学机理、能量随机分析理论及其应用

总结了国内外现有桥上列车脱轨研究中的主要问题。基于物理概念，提出了桥上列车脱轨的力学机理，进一步提出了桥上列车脱轨能量随机分析理论，其主要内容包括：列车脱轨几何准则；能反映轮轨接触状态及相对位移的列车桥梁时变系统空间振动方程组的建立；此系统横向振动激振源的确定；此系统随机横向振动的计算方法；评判列车是否脱轨的能量增量准则。计算了6个桥上列车是否脱轨实例，计算结果均与实际符合，证明这个理论有一定正确性。     

弹性管阻抗测量标准样件的设计研究

本文通过阻抗测试平台对试件阻抗限值的要求,以及弹性管标准样件机械阻抗和声阻抗的解析表达式及相关因素对阻抗影响的参数化研究,提出了标准样件具体设计的建议.所给出的计算公式和结果可作为实际阻抗测量的比较依据.     

Influence of the track quality and of the properties of the wheel–rail rolling contact on vehicle dynamics

This work describes an analytical approach to determine what degree of accuracy is required in the definition of the rail vehicle models used for dynamic simulations. This way it would be possible to know in advance how the results of simulations may be altered due to the existence of errors in the creation of rolling stock models, whilst also identifying their critical parameters. This would make it possible to maximise the time available to enhance dynamic analysis and focus efforts on factors that are strictly necessary. In particular, the parameters related both to the track quality and to the rolling contact were considered in this study. With this aim, a sensitivity analysis was performed to assess their influence on the vehicle dynamic behaviour. To do this, 72 dynamic simulations were performed modifying, one at a time, the track quality, the wheel–rail friction coefficient and the equivalent conicity of both new and worn wheels. Three values were assigned to each parameter, and two wear states were considered for each type of wheel, one for new wheels and another one for reprofiled wheels. After processing the results of these simulations, it was concluded that all the parameters considered show very high influence, though the friction coefficient shows the highest influence. Therefore, it is recommended to undertake any future simulation job with measured track geometry and track irregularities, measured wheel profiles and normative values of the wheel–rail friction coefficient.     

Dynamic Simulation of Mechanical System for Quickfeeding Shells in Gunboat4

A mechanical system for quickfeeding shells in gunboat is particularly analyzed from a dynamic view. 3D nonlinear structural simulation is completed by means of dynamic explicit finite element method. Analysis results prove that the mechanical structure is feasible substantially, the material of outer surfaces near striking and overstress position should be improved and measures should be taken to avoid parts high temperature. And all analysis results give a principal theoretical basis for furtherwork.