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161.
李建斌 《石家庄铁道学院学报》2011,24(1):73-77
城市轨道交通的快速发展在创造良好的经济、社会和环境效益的同时,也不可避免地给城市带来了振动和噪声问题。通过对噪声源进行分析,得出轮轨噪声是城市轨道交通的主要噪声源。因此,合理选择轨道结构的型式是最为有效的减振降噪措施。通过对各种轨道结构减振型式的分析比选,得出轨道减振设计中合理、有效的减振降噪措施。 相似文献
162.
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164.
针对地铁线路产生的钢轨异常波磨问题,调研了某地铁线路的钢轨波磨情况以及基本特征,对轨道刚度、
钢轨廓形、轨距以及轨道动力特征进行测试,提出钢轨异常波磨的治理思路,并对波磨治理效果进行跟踪测试,
提出既有线以及新建地铁线路钢轨波磨的治理以及预防方案。研究表明:地铁钢轨波磨较为严重,波长在 25~
100 mm 之间;轨道垂向刚度、横向刚度整体较弱,钢轨位移大,保持轨距能力差,轮轨关系恶化,在特定频段
范围内轮轨振动加剧,从而引起钢轨波磨的产生和发展。通过更换扣件及垫板、轨道精测精调、钢轨打磨措施可
以使车内噪声降低 5~10 dB,轨面不平顺显著降低,打磨周期延长至 1 倍以上;既有线路可通过“细调查、调参
数、精维修、动态检查”治理钢轨波磨,新建地铁线路应在规划、设计、运营维护、动态验收阶段严格把关,合
理采用减振轨道,避免钢轨异常波磨的产生和发展。 相似文献
165.
地铁车辆部件作为重要噪声传递路径,其隔声性能对车内噪声有重要影响。文章以我国某型地铁车辆部件为研究对象,通过建立车内噪声预测分析模型,研究了车辆部件的隔声性能指标。结果表明,改变车门、车窗和风挡的隔声量,对车内噪声的抑制效果最显著。 相似文献
166.
汽车天窗即作为通风、采光的汽车功能部件,同时也是直接能被客户感知的部件,汽车天窗的运行时平稳、安静能提高乘员的舒适性。本文从机理上对天窗打开、关闭过程中的密封条摩擦振动进行了分析,并提出了部分影响、控制因素。设计、开发及验证阶段注意这些因素,即可避免出现这样的问题,稳定天窗总成的质量。 相似文献
167.
Zhenfeng Wang Mingming Dong Yechen Qin Yongchang Du Feng Zhao 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(3):371-398
This paper provides a new method to solve the problem of suspension system state estimation using a Kalman Filter (KF) under various road conditions. Due to the fact that practical road conditions are complex and uncertain, the influence of the system process noise variance and measurement noise covariance on the estimation accuracy of the KF is first analysed. To accurately estimate the road condition, a new road classification method through the vertical acceleration of sprung mass is proposed, and different road process variances are obtained to tune the system’s variance for the application of the KF. Then, road classification and KF are combined to form an Adaptive Kalman Filter (AKF) that takes into account the relationship of different road process noise variances and measurement noise covariances under various road conditions. Simulation results show that the proposed AKF algorithm can obtain a high accuracy of state estimation for a suspension system under varying International Standards Organisation road excitation levels. 相似文献
168.
The paper evaluates the effectiveness of various traffic calming measures from the perspectives of traffic performance and safety, and environmental and public health impacts. The proposed framework was applied to four calming measures – two types of speed humps, speed tables, and chicanes – to demonstrate its usefulness and applicability. A field experiment using probe vehicles equipped with global positioning system devices was conducted to obtain vehicle trajectory data for use in more realistic simulations. In addition, a recently developed vehicle emissions model was used for more accurate evaluation of environmental and public health impacts. The results show that chicane is better than the other types of traffic calming measures considered, except in terms of vehicle emissions. 相似文献
169.
分析引起沥青混凝土路面不平整的原因,提出对沥青混合料施工、摊铺碾压过程进行控制的措施,可有效提高路面平整度,并为同类工程提供一定的参考。 相似文献
170.
The fundamental noise generation mechanisms of road and rail vehicles are discussed with attention to noise abatement measures. Based on an evaluation of publicly available tire noise data and the European road traffic noise emission model CNOSSOS, it is shown that on the road side there is a significant noise reduction potential in the usage of low-noise tires. From a three months measurement campaign a noise model was derived to predict the maximal sound pressure level of heavy duty vehicles during a pass-by in 7.5 m distance with the parameters vehicle speed and number of axles. With help of recently published information about external costs caused by heavy duty vehicles and the noise prediction tool, a model was developed to derive a money equivalent that can be used as a bonus/malus in a heavy duty vehicle fee. As a measure at the infrastructure, the installation of low-noise pavements is an effective, durable and economically attractive measure. Recent experiences with different technologies from all over the world are compiled and evaluated. On the rail side, an overview of the possible noise reduction strategies is given, followed by a discussion of the current policy and legislation in the EU and on the national level of different European countries. 相似文献