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161.
抛石护岸工程水下抛石效果评价是工程水下质量控制的重点和难点。准确掌握和分析工程水下质量状况,对确保抛石护岸的施工质量起到了重要作用。GIS(地理信息系统)技术拥有强大的空间数据处理与分析能力,可用于对水下抛石效果进行多维度的定性与定量分析。分析结果可以准确评价施工质量、精准指导下一阶段施工、降低施工成本。通过对3个试验区的分析,总结出一般施工规律:1)由于工程区上游起始处以及下游深水侧容易产生冲刷,抛石效果较差。2)工程区中部及近岸区抛石效果较好,但容易过抛。 相似文献
162.
东流水道为长江下游典型的多分汊顺直河段,汊道交替、变化复杂,时有碍航情况发生,是长江下游重点碍航水道,也是长江“黄金航道”尺度提升的瓶颈河段。尤其近些年,在经历了西港淤堵、航道调整以及二期整治工程实施后,东流水道演变出现了新变化与新趋势。结合东流水道最新实测资料,分析其演变特点及碍航特性,揭示汊道变化的影响因素,并建立二维水沙数学模型,预测未来东流水道的演变趋势。在此基础上,提出主要维护对策及措施,为同类水道的航道维护与整治提供参考。 相似文献
163.
164.
分析地铁信号与站台门系统接口故障对运营造成的影响以及地铁新线开通初期设备故障率较高的现状,对站台门状态未反馈及站台门不联动接口故障进行分析,阐述其发生的原因、处理办法。前瞻性地提出地铁新线建设时信号与站台门接口故障隐患防范措施和思路,减少设备故障率,最大限度降低信号与站台门接口故障对运营带来的影响,为新线正常运营奠定基础。 相似文献
165.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):704-732
A fault classification method is proposed which has been applied to an electric vehicle. Potential faults in the different subsystems that can affect the vehicle directional stability were collected in a failure mode and effect analysis. Similar driveline faults were grouped together if they resembled each other with respect to their influence on the vehicle dynamic behaviour. The faults were physically modelled in a simulation environment before they were induced in a detailed vehicle model under normal driving conditions. A special focus was placed on faults in the driveline of electric vehicles employing in-wheel motors of the permanent magnet type. Several failures caused by mechanical and other faults were analysed as well. The fault classification method consists of a controllability ranking developed according to the functional safety standard ISO 26262. The controllability of a fault was determined with three parameters covering the influence of the longitudinal, lateral and yaw motion of the vehicle. The simulation results were analysed and the faults were classified according to their controllability using the proposed method. It was shown that the controllability decreased specifically with increasing lateral acceleration and increasing speed. The results for the electric driveline faults show that this trend cannot be generalised for all the faults, as the controllability deteriorated for some faults during manoeuvres with low lateral acceleration and low speed. The proposed method is generic and can be applied to various other types of road vehicles and faults. 相似文献
166.
哈大客专运粮河特大桥跨既有线连续梁采用平转法施工,为确保转体顺利进行,转体前进行了T构不平衡重试验分析,文中介绍了一种转体构件不平衡重的测试方法和应用过程。结果表明,方法有效可行,可供同类工程借鉴。 相似文献
167.
对目前轨道交通快线开通运营后轮轨侧磨情况进行深入调研,对轮轨侧磨的特点、成因进行分析,通过动力仿真计算,对比分析100 km/h轨道交通快线车辆与传统80km/h地铁车辆轮轨侧磨程度的差异,最后针对轨道交通快线的轮轨侧磨问题提出防治措施. 相似文献
168.
自中国改革开放以来我国的经济得到了飞速的提升,人们的生活质量和生活水平也在日新月异的变化,在现今时代汽车已经普及到了千家万户,成为了人们日常生活的必需品,也正因为如此汽车机械故障的原因及防范措施也逐渐受到了人们的关注,本文也就汽车故障产生的原因进行了分析,并寻找出相对应的解决策略. 相似文献
169.
170.
Liang Ling Qinghua Guan David P. Thambiratnam 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(1):1-22
Trains crashing onto heavy road vehicles stuck across rail tracks are more likely occurrences at level crossings due to ongoing increase in the registration of heavy vehicles and these long heavy vehicles getting caught in traffic after partly crossing the boom gate; these incidents lead to significant financial losses and societal costs. This paper presents an investigation of the dynamic responses of trains under frontal collision on road trucks obliquely stuck on rail tracks at level crossings. This study builds a nonlinear three-dimensional multi-body dynamic model of a passenger train colliding with an obliquely stuck road truck on a ballasted track. The model is first benchmarked against several train dynamics packages and its predictions of the dynamic response and derailment potential are shown rational. A geometry-based derailment assessment criterion is applied to evaluate the derailment behaviour of the frontal obliquely impacted trains under different conditions. Sensitivities of several key influencing parameters, such as the train impact speed, the truck mass, the friction at truck tyres, the train–truck impact angle, the contact friction at the collision zone, the wheel/rail friction and the train suspension are reported. 相似文献