Transactions on Transport Sciences, 2008 (vol. 1), issue 3
Causes of long-term deflections of large-span pre-stressed concrete box girders and recommendations on how to avoid these
V. Křístek, L. Vráblík, V. Hrdoušek
Transactions on Transport Sciences 2008, 1(3):97-102 | DOI: 10.5507/tots.2008.014
The results of the presented solutions and the developed analytical and design methods will help in creating the sufficient theoretical tools for the reliable and economic structural design of bridges without deflection impairments. The paper reviews the causes of under-estimation of long-term future deflections. Special attention is placed on prestressing - a procedure to find the optimal arrangement of tendon layout - is presented, facilitating the avoidance of tendons contributing to deflection increases. A developed computer program is freely available and a method of repair procedure and a repair example, as well as recommendations for the design...
Emissions of persistent organic pollutants from transport in the experience of the Czech Republic
V. Adamec, J. Dufek, J. Jedlička, R. Ličbinský, V. Bencko
Transactions on Transport Sciences 2008, 1(3):103-108 | DOI: 10.5507/tots.2008.015
This presentation introduces the situation of POPs transport emissions in the Czech Republic since 1993, including a prediction for the years 2010 and 2015, determination of emission factors, possibilities for their reduction, and legislative framework. From the achieved results it is evident that the emissions from road and railway transport exceeded 28 tons in 2005. The naphtalene creates more than 90 % of emissions of vehicles fulfilling EURO I-III limits. The phenanthrene (about 50 % of PAHs) predominates in emissions of older gasoline vehicles that do not fulfil EURO limits; naphtalene content isabout 10 %. Total emissions of PCDDs and PCDFs are...
Human body finite element model as an instrument for the improvement of passive safety
L. Číhalová, L. Hynčík
Transactions on Transport Sciences 2008, 1(3):109-116 | DOI: 10.5507/tots.2008.016
Recently the virtual finite element human body models have become important when used to improve the passive safety of vehicle occupants. The human body models have a significant advantage over dummies, since they are able not only to predict injuries, but also to model the whole injury mechanism. This enables the detailed analysis of injuries, and hence a more precise optimization of safety systems. To be able to use the models for this purpose, an objective model of the human body needs to be created. Such a human body model, ROBBY, is being developed at the University of West Bohemia (UWB) in cooperation with the ESI Group. This model is still being...
Load rating assessment of masonry arch bridges
Transactions on Transport Sciences 2008, 1(3):117-124 | DOI: 10.5507/tots.2008.017
Simple formulas are developed for the mass scale load rating assessment of masonry arch bridges in terms of four geometrical parameters of the bridge. The ultimate load limit state and the repeated load limit state constitute the theoretical background. The formulas are constructed as the minimum squares best suited to a set of linear and nonlinear finite element solutions of a representative selection of the country's bridge stock. The formulas are quadratic in the arch span and linear in the arch rise, arch thickness and fill depth. The method can be used for other countries' masonry arch bridge stock; the data processing programme is portable. The...
Effectiveness of drainage grooves in road wearing course
M. Moravec, K. Pospíšil
Transactions on Transport Sciences 2008, 1(3):125-134 | DOI: 10.5507/tots.2008.018
Surface drainage of road pavements with both a very low longitudinal and transversal gradient is a subject for special solutions. Drainage grooves rabbeted into the road pavement wearing course are one of them. While the costs of this kind of maintenance are not inconsiderable, the effectiveness of such a solution has not yet been independently evaluated. This paper describes experiments done in the field of assessment of the drainage grooves effectiveness.
Airbags for motorcycles situated on the tank
M. Hönig, J. Kovanda, J. First
Transactions on Transport Sciences 2008, 1(3):135-144 | DOI: 10.5507/tots.2008.019
The aim of the study is to evaluate the tank as a potential place for motorcycle airbags. The study compiles the efforts of the CTU in Prague, HTW Dresden, as well as JAWA and DELPHI, for the improvement of the passive safety of motorcycle riders. The tank shapes are taken into consideration, as to their effects on passive safety, including their suitability or unsuitability. The possibilities of the software MADYMO as a tool for an initial blue-print of any motorcycle airbag if placed on the tank are also described.