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This paper is the world first to investigate the CO2 impact of railway resurfacing in ballasted track bed maintenance. Railway resurfacing is an important routine maintenance activity that restores track geometry to ensure safety, reliability and utility of the asset. This study consisted of an extensive field data collection from resurfacing machineries (diesel-engine tamping machines, ballast regulators and ballast stabilisers) including travel distances, working distances, fuel consumption and construction methodologies. Fuel consumption was converted to a kg CO2/m using the embodied energies of diesel. Analyses showed that tamping machines emitted the highest CO2 emissions of the resurfacing machineries, followed by ballast regulators and ballast stabilisers respectively. Tamping machines processed 4.25 m of track per litre of diesel, ballast regulators processed 6.51 m of track per litre of diesel and ballast stabilisers processed 10.61 m of track per litre of diesel. The results were then compared to previous studies and a rigorous parametric study was carried out to consider long-term resurfacing CO2 emissions on Australian railway track. The outcome of this study is unprecedented and it enables track engineers and construction managers to critically plan strategic rail maintenance and to develop environmental-friendly policies for track geometry and alignment restoration. 相似文献
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纤维改性稀浆封层技术的实验应用 总被引:1,自引:0,他引:1
纤维封层和稀浆封层是二种不同的路面中修方法,然而在对普通稀浆封层设备进行改装、在稀浆中均匀地加入纤维后推铺在路面上,就形成了一种全新的结构形式--纤维改性稀浆封层.介绍了国内第一段实验路的设计、施工概况. 相似文献
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李迪 《辽宁省交通高等专科学校学报》2009,11(4):16-18
本文提出一种粘贴于铝合金空心悬臂梁的匹配光纤布拉格光栅。将FBG粘贴在悬臂梁上表面距中心轴距离附近。理论分析了FBG中心波长相对偏移量与压力的关系。实验测得将匹配光纤布拉格光栅粘贴也特殊悬臂梁后其压力灵敏度为0.002025 nm/g,是FBG压力灵敏度系数的十分之一。正是这种对外界压力的低灵敏度使得匹配光栅能更精准的跟踪传感光栅中心波长变化。 相似文献
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文章结合广东河(源)龙(川)高速公路工程实例,通过对不同荷载下的土工带的拉伸试验,得出土工带在加载过程中的变形规律,为加筋结构的计算、以及加筋材料在工程上的应用提供参考。 相似文献
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碳纤维布在连拱隧道衬砌裂缝病害治理中的应用 总被引:1,自引:0,他引:1
延安至安塞高速公路墩山连拱隧道主体工程完工后,衬砌出现了不同程度的裂缝和渗漏水等病害,通过对衬砌裂缝特征、产生原因的分析,并根据裂缝的开裂程度与发展规律,采用碳纤维布对隧道衬砌裂缝进行了局部修复和整体加固补强。由于在施工过程中严格控制施工工艺和施工质量,达到了预期效果。通过碳纤维加固模拟和监测表明:衬砌裂缝得到了有效控制,支护受力处于安全状态,围岩稳定,碳纤维布加固效果显著。 相似文献
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General concern and knowledge on climate change have been increasingly studied over the past decades. Gender differences have been found for general environmental concern and knowledge, but mixed findings exist with respect to climate change. In transportation, research has examined potential relations between environmental attitudes and transportation behavior, with mixed findings as well. Recently, the use of carbon dioxide (CO2) emissions information to influence choice has been tested with women being found more willing to pay to reduce their personal impacts, suggesting that women are either more willing to change or that their response to information on climate change is stronger. However, those studies used CO2 mass and studies that examined understanding of CO2 information as a mass have found that people struggle to understand it. If concern and knowledge about climate change differ amongst individuals, then, according to theories such as the Transtheoretical Model, the type of information used to motivate choices is likely important. Using a unique data set (n = 236) it is possible to take a first look at how gender might affect concern, knowledge, and action in terms of transportation and climate change. Further, it is also possible to examine behavioral responses to transportation climate change information. Finally, an empirical analysis is conducted of the effect of how the information is presented might differ by gender. Thus, this work aims to investigate whether gender differences might contribute to the explanation of individual behavioral responses (from concern to action) in a transportation climate change context. 相似文献
100.
Air travel is considered the biggest individual climate sin. Avoiding flying, however, seems impossible. In this paper we argue that the flight a passenger chooses can be significant. For this purpose we compared the carbon emissions of selected flights in three geographical markets. We found tremendous differences in the environmental performance of individual flights. Furthermore, we also found that flying with the most modern aircraft or flying non-stop represents, in many cases, the least polluting option. Nevertheless, we were able to show that there are exceptions to this rule. Based on our results, we provide recommendations to the industry and for further research. 相似文献