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411.
矮塔斜拉桥因其受力合理、施工简单、造型美观及造价经济的特点,在我国桥梁建设中得到了快速发展。文章以来宾市永鑫大桥主桥设计为例,介绍了该双塔单索面预应力混凝土矮塔斜拉桥各主要部位的结构设计要点,并采用相关模型计算分析了主桥结构的受力情况。 相似文献
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东海大桥是一座超长跨海大桥,它承担洋山深水港繁重的货物运输。该文介绍了其桥面铺装设计要求、桥面沥青铺装层结构设计、浇注式沥青混凝土材料组成设计及SMA混合材料组成设计。其桥面沥青铺装设计从保证良好的抗车辙性能、耐疲劳性能等出发,采用环氧树脂做防水层,浇注式沥青混凝土和沥青马蹄脂碎石分别摊铺作为下层和上层。经几年运营使用仍表现出良好的使用状态。 相似文献
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Inland waterways are vulnerable to climate change as river navigation depends on water levels. Droughts can severely disrupt inland navigation services by reducing water levels either to completely non-navigable ones or to levels that oblige operators to reduce vessel load. We analyse the impacts of droughts induced by climate change using projections of river discharge data provided by eleven different climate model runs. We consider location specific characteristics by focusing the analysis on four specific locations of the Rhine and the Danube where a substantial part of the total freight activity in the European Union (EU) takes place. For the majority of the cases and scenarios considered, a decrease of the number of low water level days is projected, leading to fewer drought related disruptions in the operation of the inland waterway transport system. Although the uncertainties from the climate projections should not be neglected, the navigation sector could benefit from global warming which means that European inland waterways might be one of the few sectors where climate change can have negligible, or even positive, impact. The average economic benefit, for the cases considered, from the decrease of low water levels by the end of the century is projected to be almost €8million annually. 相似文献
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In service period, the key to ensure the service performance of bridge is to control its material durability damage and continuous collapse better. Nowadays, most anti - collapse analysis under earthquake is for the frame structure, the theory and method of anti - collapse analysis of bridge is not systematically summarized. Taking a 4 - span rigid frame - continuous girder bridge in offshore seismic prone region as an example, a new quantitative criterion for collapse resistance was proposed based on theoretical fragility, reliability theory and concept removal method of components, which is suitable for the example bridge. The results show that the time-varying durability damage and time-varying bond - slip effect on mechanical properties of materials can't be ignored in service period; the fragility and importance coefficient increase with service life, while the robustness coefficient decreases with service life, the different optimization algorithms all improve their corresponding parameters; when the bridge reaches its designed service life, its robustness coefficient is about 25% of that of the new, when the bridge exceeds the designed service life, its robustness coefficient decay rate is low, and the residual robustness coefficient is about 18%, the bridge still has certain anti - collapse performance. 相似文献
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江河海统筹一体化在海事政务的应用研究对于适度超前顺应和促进水运现代化、推动海事治理现代化和高质量发展有着重要意义。文中通过对南通海事局江河海海事政务统筹一体化实践的分析,认为应重点推进政务标准一体化、政务服务一体化、政务功能一体化、政务资源一体化,创造性地开展相关工作,提高海事行政能力、服务能力和社会影响力。 相似文献
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刘美铭 《铁路工程造价管理》2020,(2):54-58
连续梁拱组合桥作为高速铁路大跨结构的重要桥型,一般采用先梁后拱的施工顺序。本文结合某实际工程案例,从施工难度、施工质量、施工安全、经济性、施工进度五个方面对比分析了原位支架大节段浮吊拼装和异位支架+滑移+竖直提升法两种钢管拱施工方案,最终选定原位支架大节段浮吊拼装法施工,并建立有限元模型,对支架和拱肋进行验算,验证了方案的可行性及安全性。 相似文献
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重庆渝奥大桥位于重庆市区、牛角沱嘉陵江桥上游180m,主墩P4墩位于嘉陵江南岸,基础置于多年平均最低枯水位下的砂岩上。本文总结了该墩钻孔桩施工工艺,为今后类似工程施工提供一定的借鉴与参考。 相似文献