闵浦二桥主塔下横梁预应力分析及施工技术

上海闵浦二桥工程是一座公轨两用一体化双层特大桥,主桥为独塔双索面连续钢板桁组合梁双层斜拉桥。该文通过理论模拟分析计算,对主塔下横梁施工过程预应力进行了分析,并介绍了其施工技术。     

手动油泵溢油问题的工艺分析及解决

本文针对生产现场出现的液压手动油泵排气孔溢油现象,从液压翻转机构工作原理出发,分析手动油泵溢油产生的原因,使问题得以解决,取得良好效果。     

230m网状吊杆组合梁拱桥设计分析

深汕大桥为主跨230 m网状吊杆钢混组合梁拱桥,主梁采用钢-混组合脊骨梁断面,全宽56 m,大挑臂长18 m;主拱采用二次抛物线拱轴线,六边形截面,拱高41.273 m,矢跨比为1/5.5。大桥为网状吊杆在市政超宽桥面桥梁中的首次尝试运用,对拱轴线、矢跨比、拱截面形式、拱高、拱倾角、风撑设置、吊杆间距、主梁形式等参数进行了比选分析。     

某出口米轨动车组(Tc车)车体设计及试验对比研究

介绍了使用大型通用计算机辅助工程软件ANSYS和有限元方法,对某出口米轨动车组(Tc车)进行了分析计算的过程,并通过实际物理样机试验数据与计算数据的比对,分析车身强度的可靠性。     

Statistical comparison of trace metal concentrations in wild mussels (Mytilus galloprovincialis) in selected sites of Galicia and Gulf of Biscay (Spain)

Concentrations of five trace metals (Cd, Hg, Pb, Cu and Zn) in wild mussels (Mytilus galloprovincialis) from the Galician and Gulf of Biscay areas in Spain were monitored from 2000 to 2004. A pool of mussel soft tissue was prepared using 50 or more individuals representing the available size range (35–60 mm) present at the sampling points (A Coruña, Pontevedra and Vigo–Galicia, NW of Spain—and Avilés, Bilbao and Santander–Gulf of Biscay). Metals were analysed by atomic absorption spectrometry, AAS, (flame–AAS: Cu and Zn; graphite furnace–AAS: Cd and Pb; flow injection-cold vapour–AAS: total Hg). Quality of the chemical analyses was assessed by participation in periodic QUASIMEME intercalibration exercises carried out from 2000 to 2004, while the present study was developed . Univariate statistical studies, Anova (Analysis of the Variance) and Principal Component Analysis (autoscaled data, Varimax rotation) were carried out. Differences between the two areas as well as certain temporal trends were found and, in general, the Gulf of Biscay samples showed higher metallic contents, mainly close to Avilés, where iron and steel factories thrown residues for years into a nearby coastal area.     

Findings from subjective evaluations and driver ratings of vehicle dynamics: steering and handling

This paper investigates subjective assessments (SA) of vehicle handling and steering feel tests, both numerical and verbal, to understand drivers’ use of judgement scales, rating tendencies and spread. Two different test methods are compared: a short multi-vehicle first-impression test with predefined-driving vs the standard extensive single-vehicle free-driving tests, both offering very similar results but with the former saving substantial testing time. Rating repeatability is evaluated by means of a blind test. Key SA questions are identified by numerical subjective assessment autocorrelations and by generating word clouds from the most used terms in verbal assessments, with both methods leading to similar key parameters. The results exposed in this paper enable better understanding of SA, allowing improving the overall subjective testing and evaluation process, and improving the data collection and analysis process needed before identifying correlations between SA and objective metrics.     

桥梁结构中间层隔震分析

桥梁结构中间层隔震技术是在一般桥梁结构隔震技术基础上开发出的新的桥梁结构隔震技术,在加固工程以及隔震满足不了要求的特殊工程中被大力推广使用。对桥梁结构中间层的隔震结构技术进行合理的设计可以避免或减轻地面震动对桥梁结构的影响。文章介绍了隔震概念及中间层隔震技术的工作原理,对桥梁结构中间层隔震的框架技术进行了说明,并提出桥梁结构中间层隔震设计应注意的问题。     

货物运输快捷性、准时性的经济分析

从生产，流通，消费的关系出发，通过对运输与流通之间的经济关系的详细分析，论证了发展快捷货物运输系统的必要性和意义。     

Multimodal travel groups and attitudes: A latent class cluster analysis of Dutch travelers

For developing sustainable travel policies, it may be helpful to identify multimodal travelers, that is, travelers who make use of more than one mode of transport within a given period of time. Of special interest is identifying car drivers who also use public transport and/or bicycle, as this group is more likely to respond to policies that stimulate the use of those modes. It is suggested in the literature that this group may have less biased perceptions and different attitudes towards those modes. This supposition is examined in this paper by conducting a latent class cluster analysis, which identifies (multi)modal travel groups based on the self-reported frequency of mode use. Simultaneously, a membership function is estimated to predict the probability of belonging to each of the five identified (multi)modal travel groups, as a function of attitudinal variables in addition to structural variables. The results indicate that the (near) solo car drivers indeed have more negative attitudes towards public transport and bicycle, while frequent car drivers who also use public transport have less negative public transport attitudes. Although the results suggest that in four of the five identified travel groups, attitudes are congruent with travel mode use, this is not the case for the group who uses public transport most often. This group has relatively favorable car attitudes, and given that many young, low-income travelers belong to this group, it may be expected that at least part of this group will start using car more often once they can afford it. Based on the results, challenges for sustainable policies are formulated for each of the identified (multi)modal travel groups.     

Transportation of hazardous materials on Arizona's low volume roads

This paper attempts to address the issue of transporting hazardous materials and the question whether this activity constitutes a significant problem on Arizona's low volume roads. Problems related to lack of data required for most of existing risk assessment models are discussed. A preliminary risk assessment, conducted by the use of a screening model, attested that of the total state low volume road mileage, only 30% may need further, and more detailed, hazardous materials transportation risk analysis. The remaining 70% is currently free of any significant risk.