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131.
文章分析了广西东巴凤公路目前在修建和养护中出现的病害成因,提出了防护与治理的相关性建议,为类似公路灾害的防护与治理提供参考。 相似文献
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针对路基压实质量较难检测的现状,以连续测试路基结构抗力变化信息为特色的动力学检测方法应用于路基压实质量监督工作中.通过路基结构在形成过程中抗力的变化来评价压实状态的变化,实现了在压实过程中连续实时的质量监控. 相似文献
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The term ‘scenario’ is used in the safety field to designate a prototype or a model of an accident process characterised by chains of facts, actions, causal relations and consequences in terms of damage to people and property. The prototypical scenarios, properly realized, provide a basis on which to consider the action to be taken, but also a concrete backup for accident information for use in information campaigns or training. The objective of this study is to define the prototypical accident scenarios for a particular configuration of road intersection: the skewed intersection. Limited sight distance at skewed intersections leads to safety issues. A non-skewed intersection provides the best operating conditions as drivers can easily sense the direction in which they are travelling, estimate the speeds of the opposing traffic and smoothly complete a maneuver in shorter time. In skewed intersections, instead, the ability of drivers to recognize any conflicting vehicles diminishes in comparison to right-angle intersections. The logical-deductive approach used in this paper for the determination of accident scenarios is based on an analysis of a large database of incidents, which occurred on several roads in eastern Sicily on 35 skewed intersections at three-legs. The skew angle of the minor leg of all the intersections studied is between 15° and 20°. This research allowed to develop accident scenarios related to particular configurations of intersections, compatible with the Italian rules. Prototypical scenarios are constructed using samples of accidents occurring on a particular type of study area, especially when they are based on files from in-depth investigations. The method used is an inductive approach, based on an examination of each case, grouping together similar cases and building a prototypical scenario using this case grouping. From the in-depth analysis of database accidents 9 prototypical accident scenarios have been identified for the skewed intersections. 相似文献
134.
The aim of this paper is to identify the roundabout geometric characteristics affecting the safety perception while the typical maneuvers (entry, circulation, exit) are being carried out. The tool used was an on-line questionnaire, filled out by about 1.650 respondents. Four different dimensionality reduction methods (Cluster Analysis, Correspondence Analysis, Exploratory Factor Analysis and Confirmatory Factor Analysis) were used to analyze the data collected from the survey, in order to examine the key factors affecting the safety perception during the typical roundabout maneuvers. The considerations arising from the final model are the following: 1) the respondents' opinions regarding the safety perception of maneuvers are not preconceived ideas, but they originate from specific safety perceptions due to roundabout geometric configurations; 2) the users prefer definitely single lane roundabouts; this is an important confirmation of most results in the literature; 3) it was quantified the extent of the relationship between the safety perception of the typical roundabout maneuvers and the following aspects: a) maneuver type, b) geometric characteristics of the roundabouts design elements. This is the innovative aspect of the present research whose results have implications regarding theory, infrastructure and the application of new safety technologies. 相似文献
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洋山港二期正式投入运营,东海二桥也正在规划当中,关于东海二桥的建铁路桥、公路桥还是公路铁路两用桥的争议一直没有停止过,不同的专家给出了不同的答案。本文在分析影响东海二桥建设方案选取的通过能力、投资额、营运安全和环保等四个因素的基础上,通过建立层次分析模型并求解,得出东海二桥最佳建设方案。 相似文献
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以西宝高速公路西段沥青混凝土路面的施工为例,从施工准备、摊铺、碾压及其它工艺环节控制等方面,详细介绍了要保证高等级公路沥青混凝土路面平整度施工工艺方面应采取的措施。 相似文献
140.
彩色沥青路用性能评价 总被引:1,自引:0,他引:1
自行制备了8种彩色沥青,选取几种有代表性沥青评价试验方法针入度、软化点、动态剪切、简支梁弯曲蠕变试验,对其进行试验评价。在RGB颜色体系中,对数码相机采集的彩色沥青原样、RTFOT、PAV试样的表面颜色进行比较。 相似文献