共查询到20条相似文献,搜索用时 46 毫秒
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文章通过新建隧道近距离上跨既有铁路隧道具体工程实践,分析了外部控制因素、工程地质及既有隧道支护结构等限制条件,提出了三种不同上跨方案,并综合比较了相关数值分析、工程特点与要求,最后推荐采用更为合理可行的明挖隧道方案. 相似文献
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山区公路工程地质勘察方法探讨 总被引:1,自引:0,他引:1
文章总结了山区公路工程地质勘察过程中可能遇到的主要工程地质问题,提出了处理这些问题所必须取得的工程地质资料,以及获取这些资料所应采用的主要勘察手段,分析了传统勘察手段存在的问题,提出相应的解决措施。 相似文献
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《青海交通科技》2020,(1)
该隧道地处贵州高原西部,场区属溶蚀—侵蚀地貌单元。主要采用工程地质调绘、钻探等综合勘察手段进行,基本查明隧道所处场地的工程地质条件、水文地质特征、岩土体工程地质特征,对场地稳定性做出评价,场区不良地质为岩溶、危岩体及堆积体。根据地质调绘、岩样试验等成果分析,测区野外岩土体主要物理量力学试验成果及岩体完整性系数显示,施工中易发生大规模突发性涌水、涌沙、突泥等危害,应做好防排水措施设计,避免隧道内积水,保证排水通畅。分段确定围岩级别及力学指标,围岩产状平缓,顶板岩体受爆破震动易塌落,应加强围岩支护加固措施;边仰坡开挖临空易发生垮塌,应加强坡体加固防护措施,确保安全。详勘阶段加强场区工程地质勘察,进一步查明场区工程地质条件,为初步设计提供工程地质资料。 相似文献
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对青岛胶州湾隧道一些工程地质问题的看法及建议 总被引:1,自引:1,他引:0
青岛胶州湾隧道海域段水下地质勘察极为困难,工程地质情况众说纷纭。部分人认为,湾口一带因存在湾口断裂、片麻岩、火山构造等地质条件,其岩性和地质构造复杂程度、水文地质条件之差、安全系数之低位居目前世界上现有海底隧道之首,引起了社会和建设者的广泛关注。为此,作者通过陆域段的施工实际及对相关资料分析,对隧道的地质断裂、火山口构造、透水性等地质问题提出了自己的看法,并提出了加强超前地质预报、充分论证和评估存在的地质问题、增设超前支护及预注浆、配备足够的抽排水设施、二次衬砌紧跟等建议。 相似文献
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"超限超载"的产生与发展,蕴藏着深层的内在运作机理,包含着复杂的经济社会原因.其中道路货物运输价格体系的长期扭曲失衡与成本结构的有欠合理是一个不容忽视的根本原因.为此,公路所开展了货运市场运价与成本"治超"专项研究,先后历时一个多月,行程数千公里,深入7省市运输一线,对21家典型企业和个体业户的23辆货车、24条线路进行了跟踪调查,获取了大量的第一手资料与原始数据,并对此进行了解析. 相似文献
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Ngila Mwase† 《运输评论》2013,33(3):191-206
Zambia has attempted to reduce her excessive transport dependency on her traditional transport routes via South Africa and the former Portugese colonies. The costly construction of the Tanzania‐Zambia Railway (TAZARA) was part of this diversification strategy. This article examines the nature, extent and direction of Zambian traffic, including its historical evolution. It explores further the place of TAZARA among the various routes to Mozambican, Angolan and South African ports, and the ensuing actual and potential competition. Future traffic patterns will be influenced not only by the direct and service‐oriented costs of the different lines, but also by the region's volatile and uncertain political climate. 相似文献
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针对海中箱梁现浇施工中的工程量大、工期紧迫、悬臂法施工不能满足工期要求和施工难度大等问题,文章结合青岛海湾大桥箱梁现浇施工实践,介绍以钢管桩支撑作为承载基础,采用贝雷梁与碗扣式支架相结合的支架,成功地解决现浇箱梁施工难题的方法。 相似文献
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Robert E. Paaswell 《Transportation》1973,2(4):351-371
An examination of current population statistics shows that in the U.S. more than half of the population is without immediate access to a car, and in the U.K. more than three-fifths of the population is without access to a car. This phenomenon has been accentuated by national investment in both countries in major highway programs. The term carless refers to more than just households that own no cars. It extends, in households with cars to those without licenses (old and young), the handicapped, and even the licensed drivers who have no access to the family car when it is in use elsewhere (e.g. at work). The most severely effected are those in urban areas and especially the urban poor. Transportation expenses are limited for the poor when other family expenditures (food, shelter) take a high priority. Once the work trip has been satisfied, money for other trips, for the poor, is not always available. One solution to cost-free travel is pedestrianism (walking), but this too is difficult in urban areas where the pedestrian has been overlooked in favor of the car. Solutions to problems of the carless include dial-a-ride, better public transit, and better design of urban form. 相似文献