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干线公路沥青路面养护大中修工程方案设计探讨 总被引:2,自引:0,他引:2
结合某干线路面大中修工程方案设计中的路况调查结果,对其路面使用品质加以评价,有利于得出合理的路面大中修方案。 相似文献
223.
随着改革开放以来,我国的经济得到了快速的发展,第一产业和第二产业都得到了有效的发展.众所周知,我国是农业大国,农业生产是国民经济中的重要组成部分,随着我国工业的发展,我国都农业也得到了飞速的发展.其主要为农业提供机械的生产,以促进农业的发展以及农业水平的提高.在农业机械的逐步推广,我国的农业农村发展发生了翻天覆地的变化... 相似文献
224.
通过对国防公路路面养护与修补存在问题分析,研究了稀土改性冷补材料的机理,总结了稀土改性沥青路面低温冷补养护材料具备性能良好、操作简便、无专用设备和气候条件要求等特点,该材料在低温条件下修补,既能达到传统热补沥青的要求,又能弥补热补施工的缺点。为未来公路的养护,特别是对国防公路的建设、维修和战时抢修提供了更为有效的方法。 相似文献
225.
We address the robust weekly aircraft routing and retiming problem, which requires determining weekly schedules for a heterogeneous fleet that maximizes the aircraft on-time performance, minimizes the total delay, and minimizes the number of delayed passengers. The fleet is required to serve a set of flights having known departure time windows while satisfying maintenance constraints. All flights are subject to random delays that may propagate through the network. We propose to solve this problem using a hybrid optimization-simulation approach based on a novel mixed-integer nonlinear programming model for the robust weekly aircraft maintenance routing problem. For this model, we provide an equivalent mixed-integer linear programming formulation that can be solved using a commercial solver. Furthermore, we describe a Monte-Carlo-based procedure for sequentially adjusting the flight departure times. We perform an extensive computational study using instances obtained from a major international airline, having up to 3387 flights and 164 aircraft, which demonstrates the efficacy of the proposed approach. Using the simulation software SimAir to assess the robustness of the solutions produced by our approach in comparison with that for the original solutions implemented by the airline, we found that on-time performance was improved by 9.8–16.0%, cumulative delay was reduced by 25.4–33.1%, and the number of delayed passengers was reduced by 8.2–51.6%. 相似文献
226.
Among the natural hazards that threaten transportation infrastructure, flooding represents a major hazard to highways as it challenges their design, operation, efficiency and safety. In extreme cases, it may lead to massive obstruction of traffic and direct damages to the road structures themselves and indirect damages to the economic activity and development of the region. To enable the prevention of such consequences, and the proposition of adaptive measures for existing infrastructure, this paper presents an integrated framework to identify the most vulnerable points to flooding along a highway. This is done through the combination of remote sensing information (e.g. LiDAR based Digital Elevation Model, satellite imagery), a high-quality dataset, and a quasi-2D hydrodynamic model. The forcing condition is defined using a hyetograph associated to a storm with duration of 1 day and return period of 100 years. The selected highway is located in the Mexican state of Tabasco, where extreme precipitation events and floods are frequent. Results demonstrate the ability of the methodology to identify critical water levels along the road (h > 1.50 m) at those locations where flooding has been experienced, as well as points of inspection for the highway drainage. These locations were visited in the field and maintenance problems were detected that do increase its level of exposure. We show that this framework is useful for the generation of a flood management strategy to the analyzed highway, which includes an optimum location of adaptive measures to an anticipated more intense future climate. 相似文献
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公路养护工作是维持道路正常运行的基本保证,设置养护作业区往往需要封闭部分车道,这常会给道路上的交通流带来不利影响,对养护作业长度进行优化设计可以减少这些负面影响。在考虑道路交通流量的时间变化特性基础上建立了养护作业费用模型,利用Matlab工具初步实现了在道路交通流随时间变化情况下的作业区长度优化计算,并给出了具体算例。 相似文献
229.
阐述了公路机械化养护的目的与作用,对目前我国高等级公路的机械化养护现状及管理模式进行了分析。在此基础上,提出了公路机械化养护体制的改革出路与机械化设备配备的原则。 相似文献
230.
万澄宇 《辽宁省交通高等专科学校学报》2006,8(2):27-28
本文文对我省高速公路养护机械化的基本现状作了全面介绍,提出了养护机械化的发展方向,并以此为目标,对养护机械化的发展进程进行了科学规划。 相似文献