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1.
龙抬头式泄洪洞是中低水头水电站导流洞改建泄洪洞的常用方式,但其应用受到地形地质条件限制。为解决狭窄河谷地区中低水头导流洞改建泄洪洞的布置和消能问题,通过模型实验和数值模拟并结合具体工程实际,因地制宜的提出有压突扩泄洪洞这种新型式的导流洞改建泄洪洞布置方式。研究结果表明这种方式改建的泄洪洞具有如下特点:水流直接由有压流向无压明渠流转换,流态简单,有压消能和无压消能相结合;平面上洞轴线方向可以根据地形、地质和施工条件灵活选择;工作闸门可以灵活布置;结构简单、施工方便、造价低等。这种方式改建的泄洪洞可用于中低水头大流量泄洪工程,具有较高的推广应用价值。  相似文献   

2.
以长河坝水电站泄洪放空系统及中期导流洞工程出口边坡爆破开挖为背景,分析了边坡爆破地震波对下邻地下洞室安全的影响。运用理论分析及现场监测等方法,在充分分析现场工程条件的基础上,确定了放空洞和3#泄洪洞的振动测点位置,共获得了21组爆破振动测试数据。结果表明:放空洞底脚处峰值振速为垂直方向4.32cm/s;3#泄洪洞洞壁距底板0.5m处的峰值振速为水平方向4.05cm/s;洞室与爆区的相对空间位置不同,其峰值振速所在的方向不同。认为尽管边坡爆破位于洞室群的上方且距离较近,但只要爆破方案及其参数控制得当,可以保证洞室群安全。  相似文献   

3.
以长河坝水电站泄洪放空系统及中期导流洞工程出口边坡爆破开挖为背景,分析了边坡爆破地震波对下邻地下洞室安全的影响。运用理论分析及现场监测等方法,在充分分析现场工程条件的基础上,确定了放空洞和3#泄洪洞的振动测点位置,共获得了21组爆破振动测试数据。结果表明:放空洞底脚处峰值振速为垂直方向4.32cm/s;3#泄洪洞洞壁距底板0.5m处的峰值振速为水平方向4.05cm/s;洞室与爆区的相对空间位置不同,其峰值振速所在的方向不同。认为尽管边坡爆破位于洞室群的上方且距离较近,但只要爆破方案及其参数控制得当,可以保证洞室群安全。  相似文献   

4.
李奇龙  牛争鸣  王捷 《工程力学》2016,33(2):216-223
为解决高水头泄洪时旋流洞内出现较小压强和空化风险等问题,提出了新型的阻塞旋流泄洪洞,该文对设置不同阻塞时的洞内压强特性、增压特性和空化特性进行了模型试验和理论分析。结果表明:设置阻塞后洞内压强增大明显,一定阻塞时起旋器出口附近负压消失;竖井段壁面压强增大主要受起旋器喉口压强影响,旋流洞段主要受切向流速沿径向分布和水流流层厚度影响;随阻塞增大的压强-顶托压强沿程呈分段变化特征,但在竖井洞段和旋流洞段具有较好的保持性;推导了顶托压强的计算表达式并予以试验验证;阻塞大大降低了空化空蚀风险。旋流洞内设置阻塞可以较好地解决高流速时泄洪洞内的负压和空化风险问题。  相似文献   

5.
徐成光 《工程爆破》2012,18(3):70-73
唐家山堰塞湖是2008年"5·12"汶川地震形成的最大的高危堰塞湖,其防洪度汛关系到堰塞湖下游和上游广大百姓的生命财产安全,是堰塞湖治理的重中之重。关系到安全泄洪的泄洪洞施工完毕后,泄洪洞进水口预留的挡水岩坎需在汛期来临之前拆除,以满足安全泄洪。针对挡水岩坎拆除工程地形地质条件与周边环境复杂、工期紧迫等特点,首先采用内外侧浅孔爆破使挡水岩坎瘦身,后采用横断面布置扇形深孔、两端光面爆破、抛掷爆破和松动爆破相结合,非电毫秒延时爆破并进行严密的安全防护,一次性成功地拆除了挡水岩坎。  相似文献   

6.
《工程爆破》2022,(3):70-73
唐家山堰塞湖是2008年"5·12"汶川地震形成的最大的高危堰塞湖,其防洪度汛关系到堰塞湖下游和上游广大百姓的生命财产安全,是堰塞湖治理的重中之重。关系到安全泄洪的泄洪洞施工完毕后,泄洪洞进水口预留的挡水岩坎需在汛期来临之前拆除,以满足安全泄洪。针对挡水岩坎拆除工程地形地质条件与周边环境复杂、工期紧迫等特点,首先采用内外侧浅孔爆破使挡水岩坎瘦身,后采用横断面布置扇形深孔、两端光面爆破、抛掷爆破和松动爆破相结合,非电毫秒延时爆破并进行严密的安全防护,一次性成功地拆除了挡水岩坎。  相似文献   

7.
文章论述了混凝土泄洪隧洞防渗堵漏处理的作用,对混凝土泄洪隧洞防渗堵漏技术进行了分析,并以水溶性聚氨酯化学灌浆材料为例对混凝土泄洪隧洞防渗堵漏处理的施工进行了阐述。  相似文献   

8.
针对山东汛期暴雨天气多,汛情紧急的情况,为能够使群众安全、高效、有序地撤离受灾区域,省防洪防汛指挥部决定在日照市仕阳水库组织应急防洪、防汛演练,即对泄洪闸附近大量的漂浮物进行爆破清障疏通。在漂浮物爆破分解中采用长药包串联网路及装药防水技术,精准传爆,一次成功,周边建筑物设施及人员均未受到任何影响和伤害,泄洪疏通效果比较理想。对推广爆破技术在汛期大中型水库应急疏通领域中的应用,提高应急救援施工能力,具有一定的指导意义和积极的社会效益。  相似文献   

9.
针对山东汛期暴雨天气多,汛情紧急的情况,为能够使群众安全、高效、有序地撤离受灾区域,省防洪防汛指挥部决定在日照市仕阳水库组织应急防洪、防汛演练,即对泄洪闸附近大量的漂浮物进行爆破清障疏通。在漂浮物爆破分解中采用长药包串联网路及装药防水技术,精准传爆,一次成功,周边建筑物设施及人员均未受到任何影响和伤害,泄洪疏通效果比较理想。对推广爆破技术在汛期大中型水库应急疏通领域中的应用,提高应急救援施工能力,具有一定的指导意义和积极的社会效益。  相似文献   

10.
为安全、快速地完成抗洪抢险任务,采用约束药包控制爆破法拆除横穿南澧河的拦河坝。根据炸药爆炸的作用原理、爆破漏斗理论和实践中得到的炸药能量的利用率,推算出单个药包的炸药量为200kg。为得到满足要求的泄洪槽,将3个药包顺坝面交错布置为等腰三角形,并采用复式非电起爆网路以确保安全起爆。并根据理论计算公式校核了爆破振动、空气冲击波超压和爆破飞石。实践表明,此次爆破泄洪非常成功,达到了预期的效果,可为类似工程提供参考。  相似文献   

11.
钻爆法施工的海底隧道结构防排水技术研究   总被引:1,自引:0,他引:1  
阐述了海底隧道的防排水原则,以厦门海底隧道为例讨论了钻爆法施工的海底隧道的合理排放量,提出了针对不同地层的防排水方案以及在海底隧道防排水设计施工中应注意的主要问题及需要研究的问题,提出的海底隧道防排水设计方法可为类似工程提供参考.  相似文献   

12.
预判隧道运营期排水量与二衬外水压力的关系是城市隧道设计中的关键问题,而高、低水位隧道的渗流场影响范围存在较大差别,理论预测隧道排水量和水压力时不能忽视其边界效应的作用。首先,利用地下水渗流理论、复变函数保角映射理论和二维稳态流动的复变函数理论,并结合围岩-支护结构精细化模型和气象因素,分别对高水位和低水位隧道运营期排水量及二衬外水压力进行分析,然后依托在建的深圳东部过境高速公路连接线工程,对不同注浆圈渗透系数和厚度条件下城市隧道排水量及水压力之间的关系进行研究,结果表明:无论低水位还是高水位城市隧道,二衬外水压力均随隧道排水量增加呈线性降低,且注浆圈渗透系数的变化相比其厚度的变化,对水压力随排水量的折减作用更加明显;注浆圈渗透系数的增减比例相同时,低水位城市隧道水压力随排水量的折减速率更快,而注浆圈厚度增减量值相同时,高、低水位隧道水压力随排水量的折减速率基本相同。  相似文献   

13.
Planning and designing railway tunnels with an explicit reference to safety issues is becoming of utmost importance since the combination of high speed, mixed goods–passenger traffic and extreme length of the new tunnels under design or concept evaluation, have sensitively modified the inherent safety of the railway tunnel. Although the probability of occurrence of accidental events may still be considered rather low, the possible consequences of such events in long tunnels can be catastrophic, therefore raising the overall risk to levels that may be no more acceptable. The scope of this paper is to illustrate the state-of-practice related to risk analysis of long railway tunnels. First, ambitious tunnel projects are briefly reviewed. The applicable risk-analysis procedures are then described and discussed. The problem of risk appraisal is addressed and quantitative target safety levels are proposed. Safety systems for risk reduction are outlined.  相似文献   

14.
为了对城市隧道节能环保实际效果做出评价,以南京某竖井型普通照明和竖井型LED照明两隧道为研究对象,对这两条隧道的照度分白天和夜间两个阶段进行了现场测试,并统计了两条隧道的照明用电量。对比分析了两条隧道的环境品质和运行能效,得出了两条隧道的节能环保效果,为城市竖井型隧道照明设计和管理提供一定的理论基础。  相似文献   

15.
The risk associated to road and rail transportation of some hazardous materials along two routes, one including a significant portion in tunnels, and the other following the same path, but running completely in the open, is assessed. The results show that, for rail transport, no particular risk increase or mitigation is associated to the circulation of the dangerous goods through tunnels; on the contrary, for road transport, a risk increase is generally observed in the presence of tunnels. However, for LPG, the risk curve in the open lies above that in tunnels in the high frequency–low fatality zone, according to the different evolution of the accidental scenarios in the tunnel (assuming no ventilation). The transportation of liquefied nitrogen, not hazardous in the open but potentially asphyxiating in a tunnel, gives rise to a negligible risk when performed by rail, but to a not negligible one, when performed by road. These preliminary results focused on the risk for the exposed population, suggest that it may be unnecessary to limit dangerous goods circulation through rail tunnels, while, at least for some types of dangerous goods, the circulation through road tunnels may be allowed/forbidden based on the results of a specific risk analysis.  相似文献   

16.
铁路隧道的建设正处于前所未有的大发展时期,笔者在总结大量工程成功经验和失败教训的基础上提出了铁路隧道建设的基本理念:隧道必须建成遗产工程;隧道必须进行科学的风险评估;隧道建设必须合理工期、合理造价、合理合同、合理施工方案和设计原则;隧道必须进行信息化施工。提出了单双线隧道选择、隧道纵坡及辅助导洞设置、支护结构设计以及快速施工等隧道设计原则。隧道建设的理念和设计原则可指导今后铁路隧道的规划、设计和施工。  相似文献   

17.
Complex socio-technical systems, such as road tunnels, can be designed and developed with more or less elements that can either positively or negatively affect the capability of their agents to recognise imminent threats or vulnerabilities that possibly lead to accidents. This capability is called risk Situation Awareness (SA) provision. Having as a motive the introduction of better tools for designing and developing systems that are self-aware of their vulnerabilities and react to prevent accidents and losses, this paper introduces the Risk Situation Awareness Provision (RiskSOAP) methodology to the field of road tunnel safety, as a means to measure this capability in this kind of systems. The main objective is to test the soundness and the applicability of RiskSOAP to infrastructure, which is advanced in terms of technology, human integration, and minimum number of safety requirements imposed by international bodies. RiskSOAP is applied to a specific road tunnel in Greece and the accompanying indicator is calculated twice, once for the tunnel design as defined by updated European safety standards and once for the ‘as-is’ tunnel composition, which complies with the necessary safety requirements, but calls for enhancing safety according to what EU and PIARC further suggest. The derived values indicate the extent to which each tunnel version is capable of comprehending its threats and vulnerabilities based on its elements. The former tunnel version seems to be more enhanced both in terms of it risk awareness capability and safety as well. Another interesting finding is that despite the advanced tunnel safety specifications, there is still room for enriching the safe design and maintenance of the road tunnel.  相似文献   

18.
水下隧道盾构法施工安全风险评估探讨   总被引:1,自引:0,他引:1  
随着地铁、公路等交通隧道的不断发展,隧道往往穿越江河湖泊等水体,大直径泥水平衡盾构广泛应用于水下隧道施工。大直径盾构施工风险高、控制难度大,加上水下施工不确定因素多,风险因素具有不断动态变化的特点,使得施工过程中存在较大的风险。风险评估越来越多的应用于水下隧道施工安全管理中。文章介绍了大直径泥水盾构的几个特点,并对这几个特点引起风险增大的机理进行了分析,针对风险评估常用的几中方法中存在的不足,提出了一种改进的指数法,给出了该方法的评估流程及基本计算模型,并将该方法初步应用于某水下隧道施工风险评估。该方法能够适应风险因素的变化,并且不拘泥于真实概率,通过进一步的细化和完善,能够更好地适用于水下隧道施工安全风险评估。  相似文献   

19.
随着城市地铁线网的逐渐加密,地铁线路布局越发复杂多样,多条地铁线路近距离并行或交叠运行情况越来越多,由此产生的地铁环境振动影响也更为恶劣和复杂。建立多孔隧道不同列车运行状态下环境振动影响三维动力有限元模型,计算结果同相关标准规范中的经验公式预测结果进行对比,两者吻合较好,在此基础上系统分析隧道孔数、隧道空间位置关系及列车不同交汇情况对地表振动传播规律的影响。仿真结果表明:上部隧道孔洞对下部隧道地铁列车运行引起的地表振动传播规律影响较大,且对隧道孔洞近场地表振动具有一定的遮挡作用;上下隧道水平间距相比垂向间距影响更为显著;不同列车运行状态组合方式对地表振动影响差异较大。研究结论可为地铁环境振动影响评价、地铁线路设计等提供参考依据。  相似文献   

20.
《工程(英文)》2018,4(1):112-122
The total length of the second stage of the water supply project in the northern areas of the Xinjiang Uygur Autonomous Region is 540 km, of which the total length of the tunnels is 516 km. The total tunneling mileage is 569 km, which includes 49 slow-inclined shafts and vertical shafts. Among the tunnels constructed in the project, the Ka–Shuang tunnel, which is a single tunnel with a length of 283 km, is currently the longest water-conveyance tunnel in the world. The main tunnel of the Ka–Shuang tunnel is divided into 18 tunnel-boring machine (TBM) sections, and 34 drilling-and-blasting sections, with 91 tunnel faces. The construction of the Ka–Shuang tunnel has been regarded as an unprecedented challenge for project construction management, risk control, and safe and efficient construction; it has also presented higher requirements for the design, manufacture, operation, and maintenance of the TBMs and their supporting equipment. Based on the engineering characteristics and adverse geological conditions, it is necessary to analyze the major problems confronted by the construction and systematically locate disaster sources. In addition, the risk level should be reasonably ranked, responsibility should be clearly identified, and a hierarchical-control mechanism should be established. Several techniques are put forward in this paper to achieve the objectives mentioned above; these include advanced geological prospecting techniques, intelligent tunneling techniques combined with the sensing and fusion of information about rock parameters and mechanical parameters, monitoring and early-warning techniques, and modern information technologies. The application of these techniques offers scientific guidance for risk control and puts forward technical ideas about improving the efficiency of safe tunneling. These techniques and ideas have great significance for the development of modern tunneling technologies and research into major construction equipment.  相似文献   

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