Henrikas Sivilevičius

Modelling the interaction of transport system elements

Abstract Economy and nonproductive sectors of each country could not function without a transport system (TS). Having analysed research works on the interaction of separate TS elements, it was identified that there is no common model for all types of interaction. TS consists of material (physical) objects: traffic participants and freight to be carried, a transportation process and operations’ control. TS classification scheme devised according to systematically selected criteria, showing that several criteria are often applied at the same time in official documents, is presented. Original TS physical elements’ interaction model with 6 interaction levels is presented as well. The model is suitable for all modes of transport. Six levels of interaction are distinguished: autointeraction of transport elements, the first level; TS elements’ interaction, the second level; TS elements’ interaction with external environment, the third level; interaction of transport modes, the fourth level; TS interaction with t...

Research on the quality of passenger transportation by railway

Abstract The transportation of passengers by railroads is a dynamic process because setting, wherein the process takes place, undergoes continuous changes observed at technical, technological and transportation process planning levels. Every passenger has different needs and aims and can afford different possibilities. Therefore, the conception of quality differs in each individual case. In order to be able to plan a railway trip process in a proper manner, it is important to become familiarized with passenger needs and preferences and eliminate any existing deficiencies. To this end, it is reasonable to conduct passenger surveys. The paper provides an affinity diagram of railway transportation quality factors, the elements whereof correspond to the structure of the survey questionnaire. For determining the level of the quantitative significance (weight) of indicators, there was applied the method of Analytic Hierarchy Process (AHP) developed and introduced by the American scientist T. Saaty. The scope of...

The use of AHP and rank correlation methods for determining the significance of the interaction between the elements of a transport system having a strong influence on traffic safety

A system of road transport involves vehicles, roads, traffic participants and freight that therefore closely interact. The interaction between these material elements takes place in an external environment. The process of transportation is aimed at achieving some positive results, which could increase the efficiency of the Transport System (TS). However, negative effects such as a high accident rate cannot be avoided. The road accident rate is determined by the properties of the material elements of the TS and the parameters of their interaction. Their impact on the traffic accident rate cannot be determined by a planned experiment. They also cannot be compared quantitatively, because their units of measurement are different. The paper presents a detailed description of nine types of the interaction between TS elements belonging to three various levels. The data was given to 16 transport engineering specialists as a questionnaire for expert evaluation. The paper offers a logical control methodology for fi...

Manufacturing technologies and dynamics of hot‐mix asphalt mixture production

Abstract In most countries, the pavement of motor roads, airfields and other trafficked areas is made of hot‐mix asphalt (HMA) mixture prepared by asphalt mixing plants (AMP) of various designs. The total output of HMA mixtures shows the dynamics of national road transport infrastructures development, corresponding to the increasing number of vehicles, traffic intensity and axle loading. HMA mixtures are made by using various technologies, which have some advantages and disadvantages. The paper presents technological schemes of making HMA mixtures used in Lithuania and other countries. The development of AMP and technical and technological characteristics of new computer‐aided AMP models used at various asphalt production companies (APC) were analysed. Based on the data provided by the European Asphalt Pavement Association (EAPA), the correlational‐regression relation between the countrys area and the amount of the produced HMA mixtures was established. The data on the total output of HMA mixtures in Li...

Multiple criteria selection of pile-column construction technology

Abstract Numerous alternatives exist for foundation systems and construction technologies. The systems can be described by different criteria values which are incorporated in the conventional design process. Decision on the most suitable construction technology is vital for success and depends on many effectiveness criteria. The business success depends on the right choice. The mandate of a construction management researcher is to use rational, systematic, science-based techniques to inform and improve various decisions. The paper presents multiple criteria decision making model for selection of a pile-column technology. The technological criteria are determined by an experimental study. Based on in-situ investigation of natural soil conditions, criteria values are determined. The decision making model incorporates five different methods and techniques. To solve a problem, it uses three multiple criteria decision making methods. Integrated criteria weights are determined by using the analytic hierarchy pr...

REGULARITIES OF DEFECT DEVELOPMENT IN THE ASPHALT CONCRETE ROAD PAVEMENTS

Abstract A new classification of asphalt concerete pavement defects is presented in the article and the causes of their development are systematised. The dynamics of asphalt concrete pavement defect development in the road and the dependence of pavement deterioration on the type of defects are presented in the theoretical graphic model. The change of road pavement structural strength (stiffness modulus) depending on the pavement service life is also described. The dependence of the level of asphalt concrete pavement on the most important roads of the Republic of Lithuania (road Vilnius-Kaunas [Al] and motorway Vilnius Panevėžys [A2]) measured with one-wheel dynamometric trailer PKRS-2U (Russia) on the level of pavement deterioration has been identified through experiments. The analysis of the dependence of transport costs and driving speed on road pavement level has been carried out. Regression equations of such dependence and correlation coefficients as well as relations are presented too.

Tyre Rubber Additive Effect on Concrete Mixture Strength

Abstract This article describes the observed and examined effect of crumb rubber on the strength (compressive, bending and splitting tensile) of concrete. The tests have shown that the change in the strength of concrete with crumb rubber waste additives can be forecasted from exponential equations. These relationships enable to foresee the regularities of strength properties when a certain amount of crumb rubber of a certain size fraction is added to concrete. The obtained exponential equations show that concrete compressive, flexural and splitting tensile strengths decrease with increasing crumbed rubber additive amount. The testing has also shown that the addition of a small amount of crumbed rubber slightly increases (7%) the tensile splitting strength. The reason is better adhesion of the cement stone with rubber particles compared to the adhesion of sand, which was replaced by crumbed rubber. With higher content of crumbed rubber additive in the concrete, the tensile splitting strength decreases due ...

Expert evaluation of criteria describing the quality of travelling by international passenger train: technological, economic and safety perspectives

Abstract The goals, needs and possibilities of interested parties (administration, service staff and passengers travelling in a train) should be taken into account when organizing passenger transportation and making decisions concerning particularly this area. Improvement in passenger transportation (train travel) depends on experience, qualification and decisions made by the experts involved in this process. The paper analyses the performance of the joint-stock company Lietuvos geležinkeliai and examines criteria describing the quality of passenger transportation provided by this organization. The article presents the methods for showing the consistency of respondent and expert judgements on ranking the sets of criteria defining the quality of travelling by train. The significance of the considered criteria is based on a pair wise comparison. The employed method allows for determining the normalized weights of particular criteria with respect to other criteria of the analysed group (A, B, C, D). The arti...

Dependences of SMA mixture and its bituminous binder properties on bitumen batching system, mixing time and temperature on asphalt mixing plant

AbstractBitumen holds the aggregate in hot mix asphalt (HMA). Without asphalt binder, HMA would simply be crushed stone or gravel. A bitumen batching system (BBS) is comprised of bitumen storage, transportation, weighing and discharge equipment in an asphalt mixing plant (AMP). The function of the equipment is to batch the binder heated up to working temperature and to discharge it into a mixer in batches. In the entire system, the binder is exposed to high temperature and oxygen. Bitumen is slowly oxidized when it is in contact with oxygen. The degree of oxidation is highly dependent on temperature, time and thickness of a bitumen film. This article models the key factors influencing on the dynamics of bitumen oxidation in BBS equipment. Stone mastic asphalt (SMA) mixture was produced from the same materials according to the same job-mix formula (JMF) in neighbouring batch type AMP by changing the mixing time of materials from 20 to 60 s. Bitumen binder was separated from the taken SMA samples and its gr...

FRACTURE OF CONCRETE CONTAINING CRUMB RUBBER

Abstract Every year, colossal amounts of used and non-biodegradable rubber tyres are accumulated in the world. Experience shows that the most efficient way to increase the concrete fracture energy G F (N/m) is to use metal or polypropylene fibres. The optimal content of fibre increases concrete resistance to stress (especially tensile stress under bending force). Concrete fracture is not brittle; concrete continues deforming after maximum stresses and is able to resist certain stresses, there is no abrupt decrease in loading. The research has proved that crumb rubber can be used in concretes as an alternative to metal and polypropylene fibres. The investigation has found that rubber waste additives, through their specific properties can partly take up tensile stresses in concrete and make the concrete fracture more plastic; besides, such concrete requires a significantly higher fracture energy and concrete samples can withstand much higher residual strength at 500 µm crack mouth opening displacement (CMOD...