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991.
992.
布袋注浆桩施工工艺及造价指标分析 总被引:1,自引:0,他引:1
李兴远 《铁路工程造价管理》2008,23(4):22-24
根据布袋注浆桩施工情况,结合现场施工记录和收集的资料,对布袋注浆桩从施工工艺流程的设计到成孔设备的选择,从振动沉管机成孔施工步骤到注浆中注浆管及布袋绑扎、下放、拌制浆液及注浆都作了详细的分析。并根据人员组织、材料消耗和主要施工机械设备的消耗,对布袋注浆桩施工技术的造价成本指标进行了分析。 相似文献
993.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):507-528
In the first part of this study, the potential performance benefits of fluidically coupled passive suspensions were demonstrated through analyses of suspension properties, design flexibility and feasibility. In this second part of the study, the dynamic responses of a vehicle equipped with different configurations of fluidically coupled hydro-pneumatic suspension systems are investigated for more comprehensive assessments of the coupled suspension concepts. A generalised 14 degree-of-freedom nonlinear vehicle model is developed and validated to evaluate vehicle ride and handling dynamic responses and suspension anti-roll and anti-pitch characteristics under various road excitations and steering/braking manoeuvres. The dynamic responses of the vehicle model with the coupled suspension are compared with those of the unconnected suspensions to demonstrate the performance potential of the fluidic couplings. The dynamic responses together with the suspension properties suggest that the full-vehicle-coupled hydro-pneumatic suspension could offer considerable potential in realising enhanced ride and handling performance, as well as improved anti-roll and anti-pitch properties in a very flexible and energy-saving manner. 相似文献
994.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):737-766
The goal of the present study is to show how it is possible to estimate online the individual torques applied at each wheel of an automotive vehicle by using an unknown input observer together with a simple nonlinear state-space model. The necessary measurements are the steering angle, the usual rotation speed of each wheel plus the vertical load at the centre of each wheel. By doing this, this study anticipates the affordability of a new generation of wheel bearing with embedded measurements of transmitted forces. Successful simulated experimentations using a realistic simulator are shown. Validations are done using classical case studies of longitudinal, lateral and coupled dynamics. The present limits and some possible improvements of the proposed method are also discussed. 相似文献
995.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(7):575-595
This paper discusses the nonlinear properties of inerters and their impact on vehicle suspension control. The inerter was recently introduced as an ideal mechanical two-terminal element, which is a substitute for the mass element, where the applied force is proportional to the relative acceleration across the terminals. Until now, ideal inerters have been applied to vehicle, motorcycle and train suspension systems, in which significant performance improvement was achieved. However, due to the mechanical construction, some nonlinear properties of the existing mechanical models of inerters are noted. This paper investigates the inerter nonlinearities, including friction, backlash and the elastic effect, and their influence on vehicle suspension performance. A testing platform is also built to verify the nonlinear properties of the inerter model. 相似文献
996.
传统的土压力理论根据墙后土体极限平衡所得,没有考虑极限状态下土体的速度边界,为上限解或下限解.文中基于滑移线法,利用上下限定理,对墙后土体的静力场和速度场进行了计算,分别求得考虑和不考虑墙土摩擦时,土体中的应力场、速度场和土压力分布.计算结果表明:考虑墙土摩擦时,极限状态对应的速度边界条件为挡土墙转动加平动状态;不考虑墙土摩擦时,土压力和朗肯土压力一致,对应挡土墙平动状态. 相似文献
997.
介绍了机车乘务员出乘时“三交三问”培训、考试系统,系统有机地将“三交三问”培训考试、用户管理、题库管理、成绩查询、考试分析、数据备份与还原等模块集成在一起,充分利用了模块化的设计思想和开发方法,探索出机车乘务员班前针对性教育的新路子。 相似文献
998.
根据提速客车转向架橡胶球铰的结构特点,结合橡胶的本构模型及相关系数,利用ABAQUS软件对其径向刚度、轴向刚度、偏转刚度和扭转刚度进行了分析,并将计算结果和试验结果进行了比较。结果表明:计算结果和试验结果具有较好的一致性,利用有限元分析能指导橡胶球铰及同类产品的结构设计。 相似文献
999.
1000.
以襄渝铁路流水河右线大桥4号墩为工程背景,运用有限元法对钢吊箱施工过程进行力学效应分析。主要研究钢吊箱施工过程的稳定状况和变形状态,为施工提供数据支持,优化施工控制方案。同时对钢吊箱进行试验研究,试验结果与计算结果基本相符,说明计算模型正确。所得结论可为实际工程的计算和设计提供一定的理论参考。 相似文献