Flexible Overlap Technology for the Lining Trolley of Single-track Railway Tunnels北大核心CSCD

Falling-off of rock piece at tunnel arch and invert heave are the main potential safety problems affecting normal operation of the railway tunnel. The reasons causing falling-off of rock piece include squeezing by lining trol⁃ ley at construction joint, concrete cutting by cantilever end of water stop at construction joint, construction cold joint at arch, concrete quality deficiency and so on. To eliminate the falling-off of rock piece at tunnel arch caused by rig⁃ id overlap, modification of lining trolley and the flexible overlap technique combining tray with rubber gasket were adopted during the construction of Nuwashan tunnel on China-Laos railway, and the potential quality problem due to rigid overlap at construction joint of tunnel lining were effectively solved. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Experimental and Numerical Study on the Behaviors of Deep-Buried Water-Storage and Drainage Shield Tunnels北大核心CSCD

Deep-buried water-storage and drainage shield tunnels, which are different from road and subway shield tunnels in terms of computation theory, construction technology and operation maintenance, would bear high inner water pressure and large earth pressure. In view of the change of the bearing mode for the lining structure of water-storage and drainage shield tunnels, a full-ring test and numerical analysis are carried out to study the influence of inner water pressure, staggered joint assembly and bolt installation types on the behaviors of water-storage and drainage shield tunnels. The results show that the deformation of the straight-jointed water-storage and drainage shield tunnel varies greatly from the state of empty water to that of full water; and the vertical and horizontal convergence deformations of the tunnel with inner water pressure of 0.6 MPa are 2.2 times and 3.2 times of that without inner water pressure, respectively. The convergence deformation, and the maximum joint opening and bolt tension of stagger-jointed lining structure decrease by 15%-25% and 25%- 40%, respectively, compared with that of the straight-jointed water-storage and drainage shield tunnel. The bolts at the segmental joints will yield because of the increase of inner water pressure and the first occurrence of bolt yield phenomenon is located near the position on the lining structure which is under the action of maximum negative bending moment; because the failure of shield tunnel is always caused by the yield of joint bolts, this position is the weak point for the deep-buried water-storage and drainage shield tunnel. For the water-storage and drainage shield tunnel based on the connection with double rows of bolts, the bolts near the outer arc surface of segmental joints in the area of 90 degree in the vault and arch bottom can be removed; the bolts near the inner arc surface of the segmental joints within the 90 degree of the haunch must be installed, otherwise, the tensile force of the bolts at the segmental joint near the maximum negative bending moment will increase by 5%-14%. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

新型船舶燃油预热转运技术应用分析

针对传统船舶燃油加热技术存在的一些问题,介绍了一种新型燃油预热转运技术应用原理,并对该技术进行了实用性分析,提出了新船加装和老船改造该技术系统应考虑的相关问题。最终得出结论:新型燃油预热技术操作简捷,系统容易管理,实用性强,大大降低了蒸汽使用量,达到了节能减排双重功效,是值得应用于船舶的加热技术,对航运企业有一定借鉴意义和参考价值。     

What encourages people to carpool? An evaluation of factors with meta-analysis

Non-household carpools (where two or more commuters from different residences travel together in the same private vehicle) bring public benefits. To encourage and incentivise it, transport practitioners and researchers must understand its private motivations and deterrents. Existing studies often report conflicting results or non-generalisable findings. Thus, a quantitative systematic review of the literature body is needed. Using meta-analysis, this study synthesised 22 existing empirical studies (representing over 79,000 observations) to produce an integrated review of the carpooling literature. The meta-analysis determined 24 non-household carpooling factors, and their effect sizes. Factors such as number of employees (\(\bar{r} = 0.42\)), partner matching programs (\(\bar{r} = 0.42\)), female (\(\bar{r} = 0.22\)) and fixed work schedule (\(\bar{r} = 0.15\)) were found to have strong effects on carpooling while judgmental factors (such as the motivation to save costs) only exhibited small influence (\(\bar{r} < 0.1\)). Based on the significant effects, the paper discussed prospects for improving carpooling uptake by developing: (i) target demographics, (ii) selling points for marketing, (iii) carpooling partner programs and (iv) multiple employer ‘super-pools’. The results warrant caution due to the small amount of studies synthesised. Transport practitioners might plan carpooling policies based on the findings; and transportation researchers might use the list of factors to model carpooling behaviour.     

58m多用途拖船下水计算分析

着重介绍了58m多用途拖船#2船在较低水位下水时采取的改善措施,对下水计算结果进行验证分析以确定下水计算的正确性。     

长沙-株州-湘潭区域轨道交通建设必要性分析

借助于长沙-株州-湘潭区域轨道交通建设必要性的研究,总结提出了适合区域轨道交通建设必要性分析体系.该体系分为三个层次:宏观层、中观层是及微观层.宏观层是从分析区域轨道交通功能定位及国内外城市群轨道交通发展趋势的角度来判断区域轨道交通建设的必要性;中观层是研究必要性分析框架的内容,将必要性分析分为交通需求的需要、规划上的需要、城市经济的需要、环境能源的需要等四大方面;微观层系针对中观层的框架内容进行与目标区域轨道交通建设必要性相符的深层分析.介绍了长沙-株州-湘潭区域轨道交通建设必要性分析的基本过程及内容.     

哈大铁路客专德惠制梁场箱梁混凝土蒸养和压浆施工工艺

结合哈大铁路客专德惠制梁场箱梁预制的施工经验,介绍了箱梁混凝土蒸养和压浆施工工艺,以及现行技术条件与传统箱梁压浆工艺的矛盾、压浆工艺的改良等。施工结果表明,取得了较好的实际效果,对类似箱梁施工有一定的借鉴意义。     

从冷藏箱的双剂更新看全球气候变暖(续前)

2冷藏集装箱生产工艺必须创新全世界的各个生产制造领域对防范地球表面升温的问题都在采取积极的措施。那么,这一现实对集装箱行业的影响程度究竟如何,或者我们是否能够有所作为?可以肯定的是,在《京都议定书》中已经确认H FC也和C FC一样,都是使全球变暖的罪魁祸首之一,因而明     

基于ASP．NET的北京公交票务管理系统设计与实现

票务管理是公共交通管理的一个重要组成部分,但目前北京公交票务管理还保留着传统的纸上作业方式,存在信息处理易错,信息不透明、交互不及时等问题。本文从系统需求分析出发,设计了基于ASP．NET的北京公交票务管理系统,实现了票务管理中配票,结款,统计报表等核心功能。系统的实施情况表明使用该系统可有效地提高公交票务管理效率,达到了预期的目的,最后提出了系统的可进一步完善之处。     

岩溶地区公路地基岩体质量分级探讨

进行岩溶地基稳定性评价,关键在于查明岩溶的形态和计算参数的确定。现有的勘查方法确定了岩溶的形态。从岩体质量分级入手,研究了公路岩溶地基计算参数的确定方法,并提供了丰富的表格,为方便快速地确定各项参数提供了一种思路。