59 research outputs found
Book ‘Aplinkos apsauga keliuose’ review
"Book ‘Aplinkos apsauga keliuose’ review." Journal of Environmental Engineering and Landscape Management, 20(4), pp. 316-31
Thermal conditions of road pavements and their influence on motor traffic
The article presents the analysis of climatic conditions in the Republic of Lithuania and describes their influence on road asphalt concrete pavement. Dependence of the main properties of asphalt concrete mixtures on temperature is described with the help of carried out experiments. Research findings show that the probability of plastic deformations (rutting and corrugation) in asphalt concrete pavement is higher when the pavement temperature is 20-40 °C. Practical application of the presented conclusions and recommendations will enable to reduce the occurrence of undesirable deformations in asphalt concrete pavements and to improve traffic conditions on the roads
Investigation into traffic flows on high intensity streets of Vilnius city
The measurements and analysis of traffic intensity were performed in the capital city – Vilnius, the largest urban area in Lithuania. Vilnius is a centre of business, industry and tourism, and therefore traffic intensity remains the highest in this part of the country. The intensity of vehicle traffic is not only generally calculated but also simultaneously classified which means is divided predefining vehicles into beforehand established categories. Data on traffic flows are used in a road maintenance program for calculating and assessing air pollution, ensuring traffic safety, regulating traffic flows etc. The article presents the methods for measuring traffic intensity which are and were used for calculating traffic intensity not only in the streets of Vilnius but also across Lithuania. Data on vehicle intensity and classification are collected either using technologies (loop and tube detectors, counters and video detectors) or expressing them visually. The article presents the dynamics of changes in the traffic volume on the roads of Lithuania for the period 2000–2009. Also, this article examines traffic intensity of all transport means, including trucks in the permanent traffic volume measuring stations that were installed near the roads in Vilnius zone (data on traffic for the period 2005–2009) and the streets of Vilnius city (data on traffic for the period 2007–2009). Data on traffic intensity were obtained by the Road Research Laboratory of the Road Department of Vilnius Gediminas Technical University in cooperation with the State Enterprise Transport and Road Research Institute (TRRI)
Geotextile Selection Methods for the Lithuanian Road and Street Structures
This summary of the author’s PhD thesis supervised by Prof Dr Alfredas Laurinavičius and defended on 7 December 2007 at the Vilnius Gediminas Technical University. The thesis is written in Lithuanian and is available from the author upon request. In chapter 1 describes the existing problem, the need for the use of geotextiles for the separation of road and street structures. Also, the relevance of the research, the scientific novelty and originality of the dissertation, its aim and practical importance. Chapter 2 presents analysis of the geotextile selection methods for the separation of structural layers. In chapter 3 presented experimental research of the use of geotextiles for the separation of roads and streets pavement structure layers. Finally in chapter 4 the geotextile selection method for the use in the Lithuanian roads and streets pavement structures is presented. Developed geotextile selection method reflects the need for the use of geotextile, takes into consideration the factors having the impact on the occurrence of geotextile damages during pavement installation and in the course of road operation
MICROWAVE INVESTIGATION OF MAGNETIC PERMEABILITY OF MANGANITES
The real µ /µ0 and imaginary µ /µ0 parts of the relative magnetic permeability of La0.7Ca0.3MnO3 thin films and the influence of the electric permittivity and resistivity on the measurement results were investigated under microwave radiation of 10 GHz frequency employing the waveguide measurement and splitter methods
Non-Destructive Material Homogeneity Evaluation Using Scanning Millimeter Wave Microscopy
Millimeter wave bridge technique for non-destructive material homogeneity characterization is described. The idea of this technique is the local excitation of the millimeter waves in the testing material and the measurement of the transmitted (reflected) wave amplitude and phase in different places of it, i.e. the material plate is scanned by the beam of the millimeter waves. The results of the homogeneity measurements for dielectric wafers according to dielectric constant anisotropy are presented. The measurement technique sensitivity is discussed
Non-Destructive Material Homogeneity Evaluation Using Scanning Millimeter Wave Microscopy
Millimeter wave bridge technique for non-destructive material homogeneity characterization is described. The idea of this technique is the local excitation of the millimeter waves in the testing material and the measurement of the transmitted (reflected) wave amplitude and phase in different places of it, i.e. the material plate is scanned by the beam of the millimeter waves. The results of the homogeneity measurements for dielectric wafers according to dielectric constant anisotropy are presented. The measurement technique sensitivity is discussed
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