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This study presents the hierarchical structure of 50 sub-criteria divided into 7 main criteria for the assessment of electric vehicle (EV) deployment. Two options, Average Rank Transformations and Analytic Hierarchy Process methods, were applied in determining the local weights of the sub-criteria. The sufficient compatibility of expert opinions was accomplished using the averages of the ranks of the main criteria and sub-criteria as the result of solving the problem. The averages of the local weights were calculated employing three Multiple Criteria Decision-Making methods that increased the reliability of the research results. Based on this, the global weights and priorities of the sub-criteria were evaluated. The experts suppose that EV deployment at the national level is mainly affected by the higher cost of manufacturing and purchasing EVs, the application of financial incentives for purchasing EVs, the lack of exhausted gasses, the installation of fast charging points, and the absence of infrastructure in the five largest cities nationwide. The obtained results demonstrate that out of 50 sub-criteria, the cumulative global weight of the 10 most important sub-criteria (mainly based in economics) amounts to more than 35%, whereas that of the 22 most important sub-criteria have a weight above the average (0.2), reaching approximately 65%. The findings can be put into practice by state decision makers of EV deployment.

Human activities are related to obtain economic, technical, social and environmental benefits. The road construction process participants and road users have direct or indirect benefits from elaboration of new infrastructure. The number of the benefits received by individual entities is publicly discussed by politicians, lobbyists, experts and other decision-makers without having quantitative estimates of benefits, i.e., often relying on intuition or considering theoretical reasoning. The paper suggests a system of 19 benefit entities (criteria) assigned the ranks given by experts. The study involved three categories of experts, including 35 road engineers, 36 transport engineers and 61 road users. The values of the concordance coefficients obtained as a result of the conducted research were found significantly higher than critical values and showed that the opinions of the experts in each category were consistent (not contradictory). This made it possible to consider the average of the opinions of the expert group as a reliable result of solving the problem. Rank averages were replaced by the normalized weights of criteria using Average Rank Transformation into Weight-Linear (ARTIW-L) and – Nonlinear (ARTIW-N) methods. The global averages of criterion weights were used employing the Inverse Hierarchy for Assessment Main Criteria Importance (IHAMCI) method thus calculating the normalized weights of the road-related classified entities (three main criteria). The findings prove that road users benefit the most (weight 0.3485), the road construction contractor (weight 0.3325) is in the next position and the road owner (investor) takes the weight equal to 0.3190. The generated research data can be used for justifying the rationality of road investment.

Railway rolling stock must meet the requirements related to its use in the transportation process. The significance of these requirements can be determined using expert testing methods. The current research offers a framework of 9 criteria, which have been developed by the authors of the study, and which contribute to a comprehensive assessment of their importance and priority in relation to each other using expert evaluation methods. The normalised weights of the criteria were determined using Average Rank Transformation Into Weight Linear (ARTIW-L), Average Rank Transformation Into Weight Non-linear (ARTIW-N) and Direct Percentage Weight (DPW) methods. The criteria were given ranks and percentage weights by 18 experts with consistent opinions, which made it reasonable to consider the average of the experts’ opinions as the outcome of the task. The normalised weights of the criteria have shown that the most important issues for the experts included passenger and crew safety (0.1619), passenger and train staff ride comfort (0.1330) and environmental protection (0.1201). The least important criteria for the experts cover the range per one electric charge or full tank of fuel (0.0776), the dynamic performance of the traction rolling stock (0.0849), and the purchase price, the rebate system, the duration of the warranty period (0.0911). The other 3 criteria are of medium importance. The outcomes of this study can be used in deciding on the best alternative for rail traction rolling stock.

Asphalt pavement, a component of transport infrastructure, deteriorates under the influence of destructive factors. The damages which have occurred during its period of use are repaired and the asphalt pavement is recycled when its further rehabilitation is economically and technically irrational. The material from the asphalt pavement layer that has reached its limit state is milled out or broken and crushed and then is repeatedly used in the production of hot-mix asphalt (HMA) or warm-mix asphalt (WMA) mixtures. In this paper, the dynamics of the percentage recycling ratio (RR) of old asphalt pavement material was investigated. RR represents the quantity of reclaimed asphalt pavement (RAP) used in the production of HMA and WMA mixtures in Europe and the USA, divided by the total amount of RAP prepared in the country. Factors and goals affecting it are analyzed. An original system of 10 criteria that increase the RR country has been created. Decision makers do not know which factors have the maximum influence in increasing the use of RAP and this should go in connection with environmental pollution reduction and achieving economic utility. By applying different multiple-criteria decision-making (MCDM) methods and using the importance given to these criteria by 14 experts, the normalized subjective weights of the criteria were determined. Analytic hierarchy process (AHP), rank correlation, average rank transformation into weight—linear (ARTIW-L) and non-linear (ARTIW-N), and direct percentage weight (DPW) methods were used in the study. The results show that the RAP recycle rate is close to 100% in countries with a sustainable economic background. In the Baltic countries, it is mostly increased by the adequacy of regulatory documents, the strategy promoting asphalt recycling in the country, and the homogeneity and classifying of RAP. The number and capacity of RAP stocks, the number and productivity of asphalt milling equipment and the wear and tear of the asphalt pavement have the least influence on the increase in RR. The opinions of experts in assessing the significance of all criteria are consistent. The averages of the weights of criteria determined by four MCDM methods (AHP, ARTIW-L, ARTIW-N, DPW) made it possible to obtain more reliable results. These results can be used to make strategic decisions and to create a plan of practical actions to increase the RAP recycling rate in the developing countries.

For analysis, design, and rehabilitation purposes of flexible pavements, the temperature profile of asphalt layers should be determined. The predictive models as an alternative to in-situ measurements, are rapid and easy methods to determine the temperature of asphalt layer at various depths. These models are developed based on limited field data. Hence, there is a need for developing new models for prediction of temperature profile of asphalt layers in various climatic regions. In this study, climatic data was retrieved from the Long-Term Pavement Performance (LTPP) database. The information of 33 asphalt pavement test sections in 16 states in the United States was employed for calibrating the predictive models. Using the prepared data, the temperature profile of asphalt layers was predicted utilizing four regression-based models, including Ramadhan and Wahhab, Hassan et al., Albayati and Alani, and Park et al. models. Existing prediction models were calibrated, and to predict the temperature profile of asphalt layer, new models were developed. Performance evaluation and validation of newly developed models showed an excellent correlation between predicted and measured values. Results show the ability of the developed models in predicting the temperature profile of asphalt layers with very good prediction precision (R2 = 0.94) and low bias.

Transport industry with its infrastructure sector is one the main sources of GreenHouse Gas (GHG) emissions. In parallel, this industry has the main part on gross domestic product of a high transport transit countries with a develop road network. Transport infrastructure (TI) must be continuously developed, improved, and carefully maintained accordingly traffic and goods flow with respect to safety and emissions. Renewable resources, such as Reclaimed Asphalt Pavement (RAP) and energy from sustainable sources are the main accents reducing carbon emissions in the industry. The comparison outlook of different technologies emissions in a Hot-Mix Asphalt (HMA) with RAP production at Asphalt Mixing Plant (AMP) are presented in this paper. CO2 emissions comparison of different RAP additions models and fuel types was analysed. The calculation model was presented for carbon emissions in most critical GHG generated AM production stage as new aggregates and RAP drying and heating.

Business environment is full of ups and down and this makes companies to develop different ways of using resources. By expanding life cycle of products, these ways can be cost effective and not harmful for environment. As Reverse Logistics (RL) uses a product after end of its life, it reduces pollution, therefore it has been considered as a part of sustainable development. The core goal of current research is developing a framework by which it evaluates Third Party RL Provider (3rdPRLP) using Multi-Criteria Decision-Making (MCDM) based on Fuzzy Additive Ratio ASsessment (FARAS). Thirty-seven criteria were identified, which are classified into seven main criteria. The main criteria were ranked as follows: product lifecycle position C1, RL process function C2, organizational performance C3, organizational role of RL C4, IT system and communication C5, general company consideration C6, geographical location C7. Market coverage, destination, financial considerations, integrated system, reclaim, efficiency and quality, and growth are each group’s dominant sub-criteria. In addition, the current research helps the logistics managers to better understand the key attributes’ complex relationships in the environment of decision-making. First published online 21 January 2021

Deteriorated asphalt pavement material is recycled applying proved technologies based on scientific principles and practical experience. The asphalt pavement layer during rehabilitation process is loosened by a mobile transport machine fracturing into the required material grading and called Reclaimed Asphalt Pavement (RAP). RAP is extracted while cutting asphalt chip in required depth at optimal speed by mean of changeable picks installed in a toolholder of milling machine rotating drum. During interaction with the asphalt pavement to be demolished, the wear of picks appears, and the dimensions of their elements decrease. Methodology and results of a field experimental research allowed statistically to determine and evaluate the wear dynamics of picks from 2 manufacturers are provided in this paper. The results provide that length of pick, diameter of carbide tip and diameter of steel body of picks from these manufacturers were decreasing proportionally to milled asphalt pavement surface. Applying the Fisher’s criterion it was found that the variances of the reduction of these geometrical parameters are the same and they satisfy the normal distribution according to the Kolmogorov’s criterion. All values of Student’s criterion calculated statistics were higher than the critical values, which indicated that the wear intensiveness of the picks of the 2 manufacturers differed significantly. These data can be used to select suitable picks for the milling machine according to their wear intensity. First published online 9 February 2022

The relationship between the static and dynamic deflection modulus is presented in the paper, and a correlation between the FBL physical and strength indicators is determined. The correction coefficients of dynamic measurements, as related to static beam readings, are presented. The results show that, in the absence of a static beam, static beam readings can be replaced by the readings of any of the three analysed dynamic devices, and the FBL strength can thus be measured.

This paper determines the interaction between the physical indicators of frost blanket course and its deflection modulus, measured by static and dynamic devices. The Pilot Road has been selected to examine the strength properties (deflection module) of frost blanket course. A Pilot Road consisting of 27 road sections, divided into 5 different road structures. A Pilot Road has been selected to examine the strength properties (deflection module) of frost blanket course. In this research was determined the strength of frost blanket course in road pavement structures of Pilot Road by four devices: Falling Weight Deflectometer Dynatest 8000, Light Weight Deflectometers Prima 100 and ZORN ZSG 02 and Static Beam Strassentest. The results showed no reliable correlation between the deflection modulus, measured by different devices, and the physical indicators of the frost blanket course of the road pavement structures in Pilot Road.

The choice of a particular mode of transport as an alternative to another one is subjective and usually based on an individual passenger’s approach to the evaluation of advantages and disadvantages of some particular means of transport. The paper presents the methods of analysing the reasons for passengers’ choice of travelling by train as an alternative to using air transport and the results obtained in the research. The 16 criteria (sub-criteria), describing the advantages of travelling by rail over air travel, are defined. The data of the survey questionnaire filled by 52 passengers of the Vilnius–Moscow train and the ranks assigned by them to the considered criteria are described. The average ranks of all 16 criteria and their normalized subjective weights are calculated by using a new method of average rank transformation into weight (ARTIW). The average ranks assigned by the passengers of the train to sub-criteria and the calculated global weights show what criteria are most important. Using the inverse hierarchy model based on the sub-criteria weights, the most and the least important groups of criteria are determined. The institutions and companies engaged in passenger transportation by rail, which give priority to improving the services described by the most important criteria, can make this mode of transport more attractive to people.

Nowadays, travelers can use different modes of transport, and they usually choose the most suitable and reliable mode available. The choice of one mode of transport as an alternative to another is subjective. It is usually built upon passenger attitude toward the advantages and disadvantages of using a particular mode. This article proposes analytical methods for and research results on passenger choices for sustainable train journeys as an alternative to traveling by bus. The rank averages of all criteria and their normalized subjective weights were calculated with reference to new linear (ARTIW-L) and nonlinear (ARTIW-N) methods of average rank transformation into weight. A correlation between sub-criteria rank averages and normalized weights is presented, based on the minimum number of passengers required to be interviewed to provide reliable results. The average ranks assigned by passengers to the evaluation sub-criteria and their global weights were used for determining and describing the most and least important key criteria by applying the inverse hierarchy for assessment of main criteria importance (IHAMCI) method. The analysis shows that the most important key criterion belonged to the sub-criteria characterizing economy, while the less important key criteria included ride comfort. The least important key criteria described safety and environmental protection, whose normalized subjective overall weights were the lowest. Rail transport authorities and companies involved in transporting passengers can make this mode of transport more attractive to people by giving priority to improving the services they provide to passengers.

The transport infrastructure’s pavement is made of asphalt layers, placed and compacted. The asphalt mixture is produced in an asphalt mixing plant (AMP) using expensive technological equipment which, when it becomes obsolete and worn out, is replaced with new equipment. One of the main problems related to the replacement process is that when it comes to purchasing new AMPs, the decision making involved is, in most cases, highly intuitive due to a lack of clearly defined criteria. In order to remedy this situation, this work presents an analysis of the correlation between the number of AMPs and the production of asphalt mixtures. Firstly, a correlation analysis was performed based on the European Asphalt Pavement Association (EAPA) data. Secondly, the current situation with the AMPs in European countries was analysed. Furthermore, a case study was performed and a system of nine criteria was created to identify why/when road construction companies operating in the Baltic States buy new AMPs. The weights of the criteria have been established by applying the Analytic Hierarchy Process (AHP) method. It was found that the most important criterion during the decision-making process for road construction companies is increased requirements for improving the quality of the asphalt mixture produced (criteria weight 25.0%). With a weight of 20.6%, the second vital criterion is the possibility of receiving support from European funds. The third criterion is the expectation of having a sizeable asphalt-paving site (weight 20.4%). The other six criteria are also significant, their weights varying between 1.6% and 13.5%. The industrial companies can use the obtained results for designing, producing and selling AMPs and adjusting strategic business plans.

Gravel pavement has lower construction costs but poorer performance than asphalt surfaces on roads. It also emits dust and deforms under the impact of vehicle loads and ambient air factors; the resulting ripples and ruts constantly deepen, and therefore increase vehicle vibrations and fuel consumption, and reduce safe driving speed and comfort. In this study, existing pavement quality evaluation indexes are analysed, and a methodology for adapting them for roads with gravel pavement is proposed. We report the measured wave depth and length of gravel pavement profile using the straightedge method on a 160 m long road section at three stages of road utilization. The measured pavement elevation was processed according to ISO 8608, and the frequency response of a vehicle was investigated using simulations in MATLAB/Simulink. The international roughness index (IRI) analysis showed that a speed of 30–45 km/h instead of 80 km/h provided the objective results of the IRI calculation on the flexible pavement due to the decreasing velocity of a vehicle’s unsprung mass on a more deteriorated road pavement state. The influence of the corrugation phenomenon of gravel pavement was explored, identifying specific driving safety and comfort cases. Finally, an increase in the dynamic load coefficient (DLC) at a low speed of 30 km/h on the most deteriorated pavement and a high speed of 90 km/h on the middle-quality pavement demonstrated the demand for timely gravel pavement maintenance and the complicated prediction of a safe driving speed for drivers. The main relevant objectives of this study are the adaptation of a road roughness indicator to gravel pavement, including the evaluation of vehicle dynamic responses at different speeds and pavement deterioration states.

The East-West Transport Corridor (EWTC) in the Southern part of the Baltic Sea Region (BSR) has been chosen as a practical area for implementation of a novel transportation concept called synchromodality. The main expectations in developing synchromodal transport system are related to the improvement of the transport service level, modal shift and capacities utilization of transport hubs along this corridor. However, in the absence of identification of major factors influencing synchromodal system it is difficult to evaluate a potential benefit of implementation of this new transport concept. Our main goal in this paper was, on the basis of a review and using a specific questionnaire, to determine the main indicators impacting effectiveness of the synchromodal system. Compatibility of experts’ opinions was verified by using Multiple-Criteria Decision-Making (MCDM) method. The paper will be useful for transport and logistics companies interested in moving towards synchromodal transport, as well as for future researchers. In the course of the research – using the Average Rank Transformation Into Weight (ARTIW) and Analytic Hierarchy Process (AHP) methods – it was determined that the normalized subjective weights of the five main criteria impacting synchromodality distributed in the following order: service quality, efficiency, infrastructure sufficiency, technical properties of terminals and interaction of technologies. In accordance with the Kendall’s concordance coefficient and consistency ratio values, expert opinions are consistent, which enabled the rankings of expert group averages and the eigenvector to take as a result of the task solution. The outcomes of the research presented in the paper have shown that service quality (transport time, service and waiting time, handling time, working hours, reliability and flexibility) is the most important indicator (criterion) impacting synchromodality. At the same time it is a big challenge for transport researchers because it requires to design and apply a qualitatively new mathematical models facilitating an establishment of an optimal synchromodal network and services along chosen transport corridor.

Rail transport, in competition with other modes of transport, has to improve the quality of passenger and freight transport. In order to carry passengers and goods quickly, efficiently and safely, it is necessary take maintenance railways so that their geometric parameters do not exceed the tolerances. About real railway track condition, the data is obtained by track geometry recording car, measuring seven geometric parameters dispersion. This paper presents the methodology for determining and estimating the geometric parameters of the track geometry, which shows that the track quality index (TQI) is the sum of the variance of seven geometric parameters. Experimental research on the two-track A (8km) and B (11km) a three-year period (2015-2017) for all 12-month KKI, establish their quality dynamics (change over time). These data indicate that the quality of the analyzed sections A and B was good, but due to the increasing mass (in megatons) of transported loads, there is a tendency to deteriorate. Santrauka Geležinkelių transportas, konkuruodamas su kitomis transporto rūšimis, privalo gerinti keleivių ir krovinių vežimų kokybę. Norint greitai, efektyviai ir saugiai vežti keleivius ir krovinius, būtina taip prižiūrėti geležinkelių kelius, kad jų geometrinių parametrų nuokrypiai neviršytų leidžiamųjų nuokrypių. Apie tikrąją geležinkelių kelio būklę duomenys gaunami kelmačiu išmatavus septynių geometrinių parametrų sklaidą. Šiame darbe pateikta geležinkelio kelio geometrinių parametrų sklaidos nustatymo ir vertinimo metodika, kurioje įrodyta, kad kelio kokybės indeksas (KKI) yra septynių geometrinių parametrų dispersijų suma. Eksperimentiškai ištyrus dviejų geležinkelio kelių A (8 km) ir B (11 km) trijų metų laikotarpiu (nuo 2015 iki 2017 metų) visų 12 mėnesių KKI, nustatyta jų kokybės dinamika (kaita bėgant laikui). Šie duomenys rodo, kad ištyrinėtų A ir B ruožų kelio kokybė buvo gera, bet dėl didėjančios pervežtų krovinių suminės masės (megatonų skaičiaus) turi tendenciją blogėti. Reikšminiai žodžiai: geležinkelių kelias, geometriniai parametrai, sklaida, dispersija, nuokrypiai, kelio kokybės indeksas (KKI), eksperimento duomenys, dinamikos įvertinimas.

In determination of flexible pavement layers moduli using Falling Weight Deflectometer (FWD), the pavement depth temperature should be determined and then the moduli should be corrected into a reference temperature. As direct measurement of pavement temperature is time consuming and is difficult to be determined in trafficked roads, some models are developed to predict temperature of asphalt layers through pavement depth, including BELLS model. The objective of this research is to determine correlation between actual measurement and prediction of temperature variations through asphalt layers with applying BELLS model. Ten new and rehabilitated pavement sites were selected in hot climate regions in Khuzestan and Kerman provinces in southern part of Iran. In typical hot summer days, pavement temperatures were measured at half and at one-third of the depth of asphalt layers and FWD testing were performed. Results indicated that a linear regression analysis of BELLS predicted temperatures versus measured values, provides very good correlation with actual field measurements of temperatures through the asphalt layers. Furthermore, predictions were more precise in rehabilitated pavements rather than in newly constructed pavements. Finally, using multi parametric linear fitting analysis, a new model was developed to accurately predict the temperature of asphalt layers in new pavements.

Good drainage is the most important design consideration for a road, both to miniaturize road maintenance costs and maximize the time the road is operational. The lack of good drainage lead to the structural damages and costly repairs. Many of roads are built in intensively drained agricultural land. The effective way to drain subgrades is reconstruction of existing agricultural drainage. The impact of cross-subsurface drainage system on water level fluctuation was measured using Plane geofiltration mathematical model, one of 3D geofiltration modelling programs. The hydraulic permeability characteristics were determined in field of Pikeliai, close to local road in Kėdainiai district, Lithuania. This object is composed of clay and loamy soils. Subsurface cross drains trenches spacing of 20 m, 30 m and 40 m were simulated. The hydraulic permeability of cross drain trenches and lateral trenches modelled was from 0.006 m/a day to 6 m/a day. The simulation of cross drains trenches showed that the most effective distance between them are 20 m. The highest water depression occurs when the permeability of cross drain trenches and lateral trenches is ~ 6 m/day, at the distance of 20 m. The water recession is 20 cm lower compared to the drainage systems without cross drains trenches. By installing cross drains trenches every 30 m, water recession is 10 cm lower when the trench permeability is about 6 m/day. When increasing the distance between the cross drains up to 40 m their influence disappears.

The main elements of urban transport infrastructure include: the street network with intersections, bridges, viaducts, flyovers, vehicular traffic tunnels. Unsignalized four-leg intersections and roundabouts is the largest “saturated transport flow” of the street network. Roundabouts which were designed as far back as 1970–1980 were wellfunctioning when the car ownership level was 180–200 veh/1000 inhabitants. Currently, when the level of car ownership comes to 520–560 veh/1000 inhabitants, unsignalized roundabouts operate in the “oversaturated flows” regime. The research results of the Vilnius Gediminas Technical University and other universities showed that when designing new or reconstructing existing intersections the indicators of territorial planning, transport planning, environmental protection, traffic safety should be considered. As a common indicator for assessing all other indicators a monetization (estimation in monetary terms) should be used. When preparing projects for intersection reconstruction it is recommended to apply a new method of intersection analysis and evaluation based on the principles of sustainable develop- ment of urban transport infrastructure.

This article presents results of the modelling of temperature regimes of railway construction layers in application of the SV HEAT software. To get modelling results, were used coldest winter results during 50 years. Temperature changes in railway construction layers were modelled pursuant to the data of the Lithuanian Hydrometeorological Service of March 1986–November 1987 in Vilnius region and the conducted field experimental studies. Ambient air temperature, moisture content in layers were assessed. Physical – mechanical and thermodynamic properties of the materials used to install railway construction layers were identified in the laboratory. Moisture content and temperature in construction layers were measured using sensors installed in the experimental field stand (DRETM II) set up in Slovakia. According to experimental stand results and ambient air temperature data, were modelled temperature dynamics in railway construction layers. Modelling results have shown that using Slovakia national projecting and assessment documents, Lithuania railways construction protective layer should be projected thicker. Using ambient air temperature of coldest winter during 50 years results, got frost depth was 2 m, all railway construction layers frosted. Santrauka Straipsnyje pristatoma geležinkelio kelio konstrukcijos (GKK) sluoksnių temperatūrinio režimo modeliavimo „SV HEAT“ programa rezultatai. Jiems gauti naudojami šalčiausios žiemos Lietuvoje per pastaruosius 50 metų duomenys. Pagal Lietuvos hidrometeorologijos tarnybos 1986 m. lapkričio mėn. – 1987 m. kovo mėn. Vilniaus regiono duomenis ir atliktus lauko eksperimentinių tyrimų rezultatus, buvo sumodeliuota temperatūros kaita GKK sluoksniuose. Buvo įvertinta aplinkos oro temperatūra (AOT) ir drėgmės kiekis sluoksniuose. Laboratorijoje buvo nustatytos GKK sluoksniams įrengti panaudotų medžiagų fizinės­mechaninės ir termodinaminės savybės. Drėgmės kiekis ir temperatūra GKK sluoksniuose išmatuoti jutikliais, įrengtais eksperimentiniame lauko stende DRETM II Slovakijoje. Naudojant bandomojo ruožo duomenis, buvo sumodeliuota temperatūros dinamika GKK sluoksniuose, kintant aplinkos oro temperatūrai. Modeliavimo rezultatai rodo, kad, pritaikius Slovakijos nacionalinius GKK projektavimo ir vertinimo metodikas, Lietuvos GKK turėtų būti įrengiamos su storesniu pobalastiniu sluoksniu (PBS). Naudojant šalčiausios žiemos per penkiasdešimt metų rezultatus, gautas 2 m įšalimo gylis rodo, kad GKK įšalo daugiau nei 95 cm. Reikšminiai žodžiai: geležinkelio kelio konstrukcija (GKK); aplinkos oro temperatūra (AOT); šalčio indeksas; įšalimo gylis; „SV HEAT“ programa.

The asphalt pavement made of high quality materials and having the optimal composition best resists destructive effects of environmental factors and vehicles. The optimal content of the mineral materials of the asphalt mixture and a bituminous binder is selected employing calculation and experimental methods. The properties of the designed asphalt mixture must meet the requirements of technical specifications thus reducing its cost. The paper presents algorithms for simulating the composition of the asphalt mixture applying mathematical programming techniques. The algorithms allow designing the asphalt mixture with minimal bitumen content, a low cost of the mineral part and the densest gradation assessing technological requirements for producing the mixture. Optimal bitumen content is calculated considering bitumen capacities specified for different types of rock and determined employing the most recent standard sieves screening for narrow fractions. For verifying the new proposed algorithms, a numerical experiment on the materials most commonly used in asphalt mixing plants was done. The analysis of findings indicates that the application of the algorithms assist in comparing real results. First published online: 03 Apr 2017

This paper presents a simple method to determine dynamic modulus master curve of asphalt layers by con­ducting Falling Weight Deflectometer (FWD) for use in mechanistic-empirical rehabilitation. Ten new and rehabilitated in-service asphalt pavements with different physical characteristics were selected in Khuzestan and Kerman provinces in south of Iran. FWD testing was conducted on these pavements and core samples were taken. Witczak prediction model was used to predict dynamic modulus master curves from mix volumetric properties as well as the bitumen viscosity characteristics. Adjustments were made using FWD results and the in-situ dynamic modulus master curves were ob­tained. In order to evaluate the efficiency of the proposed method, the results were compared with those obtained by us­ing the developed procedure of the state-of-the-practice, Mechanistic-Empirical Pavement Design Guide (MEPDG). Re­sults showed the proposed method has several advantages over MEPDG including: (1) simplicity in directly constructing in-situ dynamic modulus master curve; (2) developing in-situ master curve in the same trend with the main predicted one; (3) covering the large differences between in-situ and predicted master curve in high frequencies; and (4) the value obtained for the in-situ dynamic modulus is the same as the value measured by the FWD for a corresponding frequency.

Engineering improvement of roads is in many cases inseparable from the improvement of at-grade intersections, as one of the most hazardous engineering structures. At-grade intersections in Lithuania are currently subjected to intensive installation of different traffic engineering and safety measures. More and more often, to ensure road safety the measures of experimental nature are used the effect of which has not been specified yet. Therefore, for the research object three intersections were selected provided with safety islands with flexible plastic reflective posts. The research was carried out within the zone of conventional intersections with the left-turn deceleration and waiting lanes on the main roads of Lithuania. During the research the driving speeds were measured in three different locations and the changes in the speeds and in the frequency of traffic conflicts were determined. Using an analogical comparison of similar traffic engineering measures, a preliminary effect of the study measures was identified.

Snow and ice cause considerable traffic problems on roads and streets in the winter period. Timely and effective removal of these problems can prevent major car accidents. This paper presents an analysis of the efficiency of Deicing Materials (DMs) used by the Lithuanian road maintenance agencies. Five different DMs were studied by performing ice melting tests in the laboratory. DMs were evenly spread on the formed ice samples taking the same amount of grains of uniform size. The ice mass dissolved by each DM was determined at different durations of melting action, ranging from 4 to 120 min, and at different ambient temperatures, ranging from –20 to –3 °C. The obtained results of each DM were analysed, and all the tested materials were compared under different temperature conditions. In addition, the deicing speed of each DM was calculated, and the DM was categorized according to the efficiency performance. A comparison of tested DM efficiencies was carried out, and the price of one percent of melted ice was determined.

The use of high quality aggregate mixture, proper technological parameters of laying and compacting as well as the required thickness of the mixture ensures railway sub-ballast layer properties. In this paper gradation, den­sity and water permeability of 49 produced random samples of aggregate sub-ballast (ASB) mixture which were taken from the stockpile in the plant and from the uncompacted railway layer are investigated. The statistical parameters of the ASB mixture quality indicators and histograms with theoretical curves of normal distribution are presented as well. Their conformity to normal distribution was tested through the use of skewness, kurtosis, Pearson, Shapiro-Wilk and Kolmogorov-Smirnov methods. Regression analysis was employed to determine the dependence of standard deviation of percent passing on the mean percent passing through the sieves. In this paper a new method of determining the homo­geneity of ASB according to the variation of gradation using the maximum standard deviation value of this dependence was employed. The minimum size n was calculated with the permissible relative error of 5%, 10%, 15% and 20%. The obtained research findings revealed that due to segregation processes the homogeneity of ASB mixture from the point of its production to application has decreased by about 38%. First published online: 20 Apr 2016

Railway sub-ballast layer is a connecting layer between the ballast and other track layers. This layer must ensure even load distribution into the subgrade, drainage surface water, prevent materials of layers mixing. Ensuring these properties allows to extend the explotation of all railway road construction and geometrical parameter of road maintenance. This article analyzes investigated railway sub-ballast mixture properties from large sample sizes (n = 49): gradation, water permeability and density statistical parameters. The regression equation showing the relationship between the fully percent passing through sieves averages and standard deviations is presented. Her coefficient of determination (R2 = 0.909). The minimum number of representative samples of these three properties research is determined. Irregularity in most cases of water permeability (ν = 88,3%), depending on the laboratory tests methodology errors, is indicated. Santrauka Geležinkelio pobalastinis sluoksnis yra jungiamasis sluoksnis tarp balasto ir grunto sluoksnių. Šis sluoksnis turi užtikrinti tolygų apkrovos perdavimą į sankasą, nudrenuoti paviršinį vandenį, neleisti maišytis sluoksnių medžiagoms. Šių savybių užtikrinimas leidžia prailginti visos kelio konstrukcijos eksploataciją ir geometrinių kelio parametrų išlaikymą. Šiame straipsnyje yra analizuojamos užpildų mišinio, naudojamo geležinkelio pobalastiniame sluoksnyje, iš didelės imties (n = 49) gautos savybės: granuliometrinės sudėties, pralaidumo vandeniui ir tankio statistiniai parametrai. Pateikta granuliometrinės sudėties regresijos lygtis, rodanti sąsają tarp pilnutinių išbirų per sietus vidurkių ir standartinių nuokrypių. Jos determinacijos koeficientas R2 = 0.909. Apskaičiuoti reprezentatyvūs minimalūs bandinių skaičiai šioms trims savybėms tirti. Gauta, kad pralaidumo vandeniui savybė yra labiausiai nevienoda dėl laboratorinių tyrimų metodikos paklaidų, variacijos koeficientas (88,3 %). Raktiniai žodžiai: geležinkelio pobalastinis mišinys, granuliometrinė sudėtis, vandens pralaidumas, mišinio tankis, bandinių skaičius.

Due to destructive factors (traffic loads, climatic and weather conditions, improper exploitation materials), bitumen properties irreversibly change in unservicable asphalt concrete. Due to irreversible processes of oxidation the aged bitumen stiffens, its physiochemical properties, ductility, adhesion and cohesion as well as sectional composition (relative amounts of asphaltenes, oils and resins) change. Bitumen in the reclaimed asphalt pavement (RAP) may be restored to properties approximate to those of the virgin bitumen by adding the following rejuvenators: softening or rejuvenating agents as well as soft bitumen. The article presents the experimental data on RAP obtained from laboratory tests conducted with Marshall specimens without additives when RAP was supplemented by different types of virgin road bitumen, the paving grade of which was 50/70, 70/100, 100/150, 160/220, respectively. The content of newly added binder of all types to RAP was 0.5%, 1.0%, 1.5%, 2.0%, and 50/70 in addition and 4.0% and 6.0% of RAP mass. The total bitumen content increased by the same percentage amount in the reclaimed asphalt, which was not always optimal. Marshall specimens were formed with these bitumen contents, the tests of which enabled to identify stability (S), flow (F), Marshall quotient (S/F), air voids content (Vm), bulk density (SDD – ρb SD) of asphalt concrete samples and the maximum density of asphalt. Having extracted all RAP and reclaimed asphalt samples according to the differential method, the factual content of soluble binder in them and its penetration, softening point, Fraass breaking point, ductility and penetration index Ip were calculated. The dependences of the reclaimed asphalt physical and mechanical parameters on the virgin rejuvenating bitumen grade and its added percentage amount were obtained. Data analysis and their generalization was conducted.

Road asphalt concrete pavement is usually laid of hot-mix asphalt (HMA) mixture. HMA mixture is produced in an asphalt mixing plant (AMP) according to the technology applied in its structure. AMP shall meet certain requirements set in the norms not only to the quality of HMA mix produced in it, but to environmental protection as well. A possibility to produce an HMA mixture of all required types and marks in it shall be available through the use of various materials and additives, including reclaimed asphalt pavement (RAP). HMA mixture production costs shall be as low as possible. AMP shall be of appropriate technical condition and with proper equipment, which mostly influence on the technological, ecological and economic parameters. Its actual productivity shall meet the required scope (HMA mixture amount) of road construction works carried out in the serviced region. The article presents 9 criteria of operating AMP quality, mathematical models of determining their significance through the application of an expert research method as well as expert opinion correlation values. Ranks of AMP quality criteria have been replaced by their weight indices through the application of two different methodologies. Quality criteria weight indices may be used according to an additive model through the calculation of operating AMP quality multi-criteria index. A numerical sample is presented at the end of the article.

With a view to saving bitumen and mineral substances and also for the purpose of preventing environmental pollution, the old asphalt pavement (AP) may be milled without increasing the thickness of pavement structure and subjected to hot recycling for reuse in the same or any other location. However, the suitability of reclaimed asphalt pavement (RAP) for reuse depends on its composition (the content and gradation of bitumen) and the properties of its components. Hence, the present study aims at providing a systematic analysis of factors that determine the inhomogeneity of RAP. To this end, RAP samples, taken from RAP being loaded from the milling machine onto the transport means and from RAP stored in the territorial storage facilities of asphalt concrete (AC) plants, were examined in an accredited laboratory to determine, for each sample unit, the composition (the content and gradation of aged soluble bitumen), the content of moisture and the gradation of non-extracted granules. The statistical characteristics showing the actual homogeneity of RAP sampled from different sources were also estimated and analysed. Further, there was elaborated a model for comparing the homogeneity of RAP from different sample sets by the max values of standard deviations in the percentage mass passing the sieves and, based on the experimental data, derived the respective regression equation. The results of the performed comparison showed the absence of any statistically significant difference in terms of homogeneity between the three different RAP sample sets, i.e. RAP-1 sampled from the road, RAP-2 taken from the stockpiles being formed in different locations and RAP-3 obtained from RAP kept stockpiled in an open storage facility. The study was finalized by determining, in line with the Specification of Technical Requirements TRA ASFALTAS 08, the max content of RAP allowed for inclusion in a hot mix asphalt (HMA) mixture depending on the actual homogeneity of RAP determined.

Multi-attribute methods in road construction can be used on the national, organization and project levels. However, most assessment methods are seeking to find how to make the most economic construction decisions, and most of all these decisions are intended only for economic objectives. Computerised Asphalt Mixing Plants (AMP) are one of the most expensive and complicated equipments for construction of road pavements. Modern AMP is controlling by computer program, but there are still some problems. Properties of the AMP not always satisfy demands and requirements of road constructors. Quality of the asphalt hot mixtures, environmental contamination, pollution, firm economic well-being and possibility to satisfy demands of hot asphalt mixture users depend on the AMP quality. This paper proposes a multi-attribute model for efficient quality assessment of the AMP. For this problem were selected 9 main quality attributes and weighted by expert ranking method. The problem is solved by applying additive assessment. Also, a case study is presented.

It was determined that poor quality of asphalt concrete is the main cause (65 %) of early fatigue cracking of asphalt concrete pavement of roads in Lithuania and neighbouring countries with similar climatic conditions. The poor quality of asphalt concrete is mainly predetermined by production errors of hot mix asphalt (HMA) and designed suboptimal mass ratio of constituents. The development of theoretical principles for producing the best componential composition of asphalt concrete is highlighted. Optimal values of the portions of coarse aggregate, fine aggregate, filler and bitumen recommended by different authors are given. The main causes of deviations from the optimal composition of HMA produced by asphalt asphalt mix plants of different generations are systematised. The dynamics of rapid cracking of asphalt concrete paving of Lithuanian roads is shown emphasising the inadequacy of HMA structure and properties to increased traffic intensity and axial workloads. The permissible values of asphalt concrete components, optimal under the actual climate and traffic conditions, ensuring highest asphalt concrete resistance to fatigue and rational (8–9 years) service life, during which the cracked pavement area does not exceed 8 %, are proposed. A quality assurance method has been developed based on mathematical statistical methods. It helps avoid deviations of component proportions, occurring in the process of production, from the project proportion and to increase the homogeneity of the product.

The article focuses on investigation of mechanical and fracture properties of concrete containing electrical cable waste as well as some microstructural features of such concrete. Added to concrete, electrical cable waste reduces the overall concrete bulk density. Compressive, flexural, tensile splitting strengths and elastic modulus decreased when electrical cable waste was admixed to conventional and polymer modified concretes. The best mechanical properties of concrete samples containing electrical cable waste were identified in polymer modified concrete containing 5% of electrical cable waste. Electrical cable waste particles increase the deformability of polymer modified concretes and have almost no influence on normal concrete. Consequently, the optimal amount of electrical cable waste particles can provide concrete with desirable strength that is required for different applications.

More and more recycled asphalt mixtures with high reclaimed asphalt pavement (RAP) content are used in road pavement. Having determined and evaluated RAP composition (aged bitumen content and aggregate gradation) and properties, a suitable recycling agent and virgin materials are selected in the design process. The gradation of hot mix asphalt (HMA) mixture that is recycled in an asphalt mixing plant (AMP) shall correspond to its optimal gradation set out in its job-mix formula (JMF). When RAP is recycled in an AMP, inevitable systematic and random errors of performed technological operations and inhomogeneity of virgin materials and RAP have a significant influence. These factors influence the variation of components quantities of recycled hot mix asphalt (RHMA) mixture and deviations from JMF. In this study, the principles of asphalt pavement hot recycling are systematized, which allows analysis of the factors of components’ interaction influencing the results of the recycling process. The paper also presents and analyses asphalt recycling technologies in AMP and their comparative analysis. During the season of asphalt mixture production in 2014, statistical parameters were calculated according to the data obtained from one of the companies, which collected and systematized RAP batch masses, when before batching it was pre-dried and pre-heated in an additional dryer. These parameters of batch mass and RAP content in RHMA position and variation were used when evaluating the accuracy and precision of the recycling process in AMP. The obtained data showed that when RHMA mixtures are produced in a modern batch-type AMP, RAP is batched accurately, but not precisely enough.

The quality of multifaceted objects or phenomena can be hardly described or evaluated by a single criterion. The quality of the trip by train is described by a set of quantitative and qualitative criteria. The influence of all the criteria on the trip by international train may be evaluated by a comprehensive quality index (CQI) or quality index K. An additive model is offered for calculating CQI, which consists of the average weights of the criterion groups, as well as normalized weights and variables of the criteria, showing the correspondence of the real value of each criterion to the best, critical or allowable value. A mathematical model, which may be used for determining the quality of the trip by train based on the criteria describing the elements of the train and technical state of the railway track is also presented. Based on the use of 16 criteria describing the elements of the train and the parameters and the technical state of the railway track, the quantitative estimate KA (multiple criteria index) is obtained. The suggested model and the techniques used in the work may be applied to determining the quality or effectiveness of other objects or processes, which can be described by sets of criteria.

This paper addresses simulation of asphalt on the macroscopic scale, using the Discrete Element Model (DEM). Asphalt mixture is considered as a particulate solid composed of relatively stiff deformable layered spherical particles embedded into a homogenised matrix. The discrete model presents a 3D network of one-dimensional elements connecting particle's centres and comprising mutual interaction of particles. The contribution of the film layer and the interface thickness for normal stiffness is described analytically and illustrated by simulation results. Development of the normal interaction model of layered particles contacting via interface on the meso scale is the key point of the current development. The model applied aiming to simulate deformation of asphalt mixture is able to capture properties of the weaker matrix interface while layered particle comprises of bitumen film in meso scale. The developed technique is applied for simulation of Marshall test, i.e. diametric compression of cylindrical specimen, widely used for characterisation of asphalt mixtures. Finally, suitability of the model is illustrated by comparison with the available experimental results.

Bitumen 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 gradation was identified. Thus, Marshall specimens were produced and tested. Penetration Pen25 of bitumen binder recovered in rotary evaporator, softening point Tsp was determined and penetration index Ip was calculated. The presented findings of experimental investigation show that the properties of bitumen binder in BBS working at two different technologies changed inconsistently. Due to gravitation, the bitumen intensively flowing into a mixer (BBS1) is impacted by oxidation more than the bitumen batched by a high-pressure pump (BBS2).

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 filling in the questionnaire based on the Analytic Hierarchy Process (AHP) and the sequence of calculations of the consistency of expert estimates in the process of determining the weights of the investigated interactions. The Kendall's coefficient of concordance has been used for calculating the weights assigned to the criteria by a group of experts and estimating the consistency of the ranks based on them. Finally, the paper presents a new method for evaluating expert judgements with reference to the use of the correlation analysis of ranks and weights. The significance of the calculated pairwise correlation coefficients has been validated by the Student's t-test and lowest value thus allowing us to consider that the expert opinions about the impact of the interaction of TS elements on the traffic accident rate are consistent.

When exposed to destructive climate and weather factors and heavy vehicle loads, the pavement wears and deflects. In recent decades, apart from cracks and potholes, the depth of ruts grows and makes an increasing share of the pavement surface. The deeper are the tracks, the poorer are traffic conditions for fast-moving cars: drivers are struggling, speed is decreasing and the number of accidents is increasing. After track depth reaches a critical and permissible limit, the road surface must be repaired or speed limit has to be reduced. The work presents a theoretical analysis of track emergence causes and factors determining their depth. With the help of Mobile Road Research Laboratory RST 28, the track depth of all Lithuanian highways has been measured every 20 metres. The obtained data have been processed using the methods of mathematical statistics. Each road has a sample average of every rut, sample standard deviation and a coefficient of individually measured variation. The paper has drawn histograms, calculated skewness, kurtosis and normal distribution and provided lognormal distribution curves of a probability density function. The visualisation and empirical skewness and kurtosis values have revealed that the depth of the rut distributes according to lognormal rather than normal distribution. The average values of the roads having a dividing strip and standard deviations from the distribution across the road have been received. The given dependence of the rut depth of a standard deviation on the averages of rut depth shows an elastic interface of these parameters (determination coefficient R2= 0.741).

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) and deflection.

A great number of serious road accidents occur all over the world every year. In spite of some progress in this area, road traffic safety has remained an acute problem in recent years. Traffic accidents on the road depend on the following factors: road traffic volume, road traffic speed, road condition, weather conditions for traffic, driving experience and driving culture. All these factors are related to traffic safety, human lives and health. The main goal of this work is to provide a statistical analysis of traffic accidents and investigate the causes, structure, dynamics and seasonal character of traffic accidents on Lithuanian regional gravel roads. It has been established that seasons play an important role for traffic accidents on regional gravel roads in Lithuania. Rates for traffic accidents increase from spring to autumn. The number of traffic accidents on Lithuanian roads decreased considerably in 2008 and 2009.

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 process and the expert judgement method. This model could be used to solve complicated problems pertaining to the selection of a construction technology.

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 article offers an algorithm for displaying the quality of train travel. The ranks assigned to the criteria by train passengers (category K), service staff (category P) and administrative staff (category A) are calculated establishing the differences between the ranks of criteria. The opinions of the respondents and experts belonging to categories K, P and A are compared considering the significance of the adopted criteria. The paper provides the results obtained from the surveyed respondents and experts and presents the ranks given to criterion groups A, B, C, D describing the quality of train travel. Finally, the conclusions based on the performed research are presented.

The significance of the criteria describing various aspects of travel by train, e.g. passenger transportation comfort, safety, travel time, price of a journey, etc., differs considerably. The quality of particular trains, track sections and staff performance can be successfully evaluated by a single number, using the comprehensive quality index (CQI). The paper offers an additive model to calculate the normalized weight coefficients of particular criteria for CQI calculation. A multi-criteria mathematical model, which may be used for evaluating the significance of the criteria describing organization and technology of travel by train for determining its quality, is also presented. Based on the nineteen adopted criteria (the criteria of group B), reflecting the organization and technology of travel by train, the quantitative estimate KB is obtained. Case studies of calculating the comprehensive quality index KB , describing the organization and technology of travel by the train ‘Vilnius–Moscow’, which show the real quality of these processes, are presented. Finally, the conclusions based on the research results are provided.

Decision making is a vital component of success in construction management. All construction businesses recognize the painful necessity of technology choice. Good decisions mean good business. Decisions that are based on knowledge and sound reasoning can lead a company into long-term prosperity. The mandate of a construction management researcher is to use rational, systematic, science-based techniques to inform and improve decisions of all kinds. The paper presents results of an experimental study on technological indicators of pile-columns at a construction site. Based on in-situ investigation of natural soil conditions, regression equations have been determined, which can be very useful when planning similar works at a construction site. Besides, they allow determining duration and energy consumption of construction works.

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 to the significant increase of entrained air content and lower density.

Smoothness is the main feature of road exploitation. It particularly affects movement speed, safety and driving comfort. Evenness of the road belongs of three factors: strength of the pavement construction, heavy vehicle traffic and the impact of the axle mass over it’s term of exploitation. The main negative influence on Lithuanian roads has a overloaded heavy vehicle in excess of the permissible axle load limits. Static and dynamic vehicle weighing equipment and technologies were presented in the article. This article explores overloaded heavy vehicle damage done to Lithuanian roads and its intensity increase. Discuss the basic preventive techniques and methods to prevent the rapid wear of pavements. Also analysis of changes in axial load data through the 2009 August is done. Santrauka Pagrindinis kelio dangos eksploatacinis rodiklis yra lygumas. Nuo jo priklauso važiavimo greitis, saugumas ir komfortiškumas. Didžiausią įtaką kelio lygumo kitimui turi jo dangos konstrukcijos stipris, sunkiųjų transporto priemonių eismo intensyvumas ir ašių masė per visą eksploatavimo laikotarpį. Pagrindinę neigiamą įtaką Lietuvos keliams daro perkrauti krovininiai automobiliai, viršijantys leistinąsias ašių apkrovų normas. Straipsnyje nagrinėjama viršsvorinio krovininio transporto daroma žala Lietuvos keliams. Išanalizuoti dinaminio ir statinio automobilių svėrimo įrenginiai ir technologija. Nustatytas 55-tos klasės sunkiųjų automobilių viršsvorinio krovininio transporto apkrovų kitimas ir jo intensyvumo didėjimas. Aptarti pagrindiniai prevenciniai būdai ir metodai, leisiantys sumažinti spartų kelio dangos nusidėvėjimą. Išanalizuoti varančiosios ašies ašinės apkrovos kitimo duomenys per 2009 m. rugpjūčio mėn. laikotarpį. Raktiniai žodžiai: sunkieji automobiliai, viršsvorinė transporto priemonė, varančioji ašis, ašinė apkrova, perkrovos dydis, kelio danga

The paper analyses waste tyre rubber treatment technologies. According to foreign countries and Lithuanian experiment results, positive and negative features of the utilization methods are presented. Data of experiments is presented using tyre rubber in clinker burning furnaces. Here is also information on the use of rubber additive in concrete and the impact to road design. Formulated conclusions. Santrauka Nagrinėjamos naudotų padangų regeneravimo ir utilizavimo technologijos. Remiantis užsienio šalių ir Lietuvoje atliktais tyrimais, pateikiamos pozityvios ir negatyvios metodų savybės. Pateikta informacija ir duomenys, gauti deginant gumą klinkerio krosnyse. Taip pat duomenys apie gumos panaudojimą betone ir poveikį kelio dangos konstrukcijai. Suformuluotos išvados. Raktiniai žodžiai: padangų perdirbimas, guma, deginimas, termolizė, modifikuotasis betonas, utilizavimas, akustinės charakteristikos, lenkimo deformacija, pirolizė

The paper aims to determine the statistical indicators of distribution of the calculated rut depth of the state significance roads and to check their compliance with the requirements raised. The analysis of the works, investigating the problems of rut development and deepening on asphalt pavement and their effect on traffic conditions, is presented. The models of the dynamics of rut development on asphalt road pavement are also given. The experimental research aimed at determining the distribution of rut depth on the state significance highway Vilnius–Kaunas is described. The conclusions made are also presented. Article in Lithuanian. Lietuvos valstybinės reikšmės kelių asfalto dangos provėžų gylio statistinis tyrimas ir vertinimas Santrauka. Šio straipsnio tikslas – surinkus duomenis apie valstybinės reikšmės kelių nestandžios dangos išmatuotų provėžų gylį, nustatyti jo pasiskirstymo statistinius rodiklius ir įvertinti jų atitiktį keliamiems reikalavimams. Straipsnyje pateikta mokslo darbų, skirtų vėžių atsiradimo, gilėjimo asfalto dangoje ir įtakos transporto priemonių važiavimui, analizė. Pateikti vėžių asfalto dangoje dinamikos modeliai. Atlikti Lietuvos valstybinės reikšmės magistralinio kelio Vilnius–Kaunas provėžų gylio pasiskirstymo eksperimentiniai tyrimai. Suformuluotos ir pateiktos išvados. Reikšminiai žodžiai: provėža, asfalto danga, gilėjimo dinamika, transporto priemonė, statistinė analizė.

The need for improving quality of passenger transportation by rail transport to increase the competitiveness of this means of transport is demonstrated. Major criteria influencing the quality of passenger transportation by rail transport are defined and expert evaluation questionnaires, allowing the authors to obtain the data on the presented criterion significance from the respondents (service people of the train) are prepared. The searching for ways of determining suitability of mathematical statistics methods for checking the concordance of expert judgements is described. For this purpose, the AHP (Analytic Hierarchy Process) method, allowing pairwise criteria evaluation, is used. Based on the calculated average values of the criterion significance and ranks, obtained using the data elicited from the questionnaires filled by the service staff of the trains (train masters, mechanic operators-electricians, conductors, etc.), the priority order of the criteria is determined. Article in Lithuanian. Traukinius aptarnaujančio personalo nuomonės apie keleivių vežimo kokybės kriterijų svarbą nustatymas ahp metodu Santrauka. Pagrįsta būtinybė gerinti keleivių vežimo geležinkeliais kokybę, kad šios rūšies transportas tobulėtų ir taptų konkurencingu tarp kitų transporto rūšių. Susisteminti svarbiausi kriterijai, turintys įtakos keleivių vežimo geležinkeliais kokybei. Sudarytos ekspertinio tyrimo anketos, leidusios surinkti duomenis apie respondentų (traukinius aptarnaujančio personalo) nuomonę nustatant kriterijų, pateiktų anketose, svarbą. Pateikta matematinės statistikos metodų, leidžiančių nustatyti ekspertų nuomonių suderinamumą, tinkamumo paieška. Tam taikytas hierarchijų analizės proceso (Analytic Hierarchy Process – AHP) metodas, leidžiantis kriterijus lyginti poromis (Saaty metodas). Pagal traukinius aptarnaujančio personalo (traukinio viršininkų, mechanikų elektrikų, vagonų palydovų) apklausos anketinių duomenų apskaičiuotus kriterijų svarbos vidurkius ir rangus nustatyti jų prioritetai. Reikšminiai žodžiai: geležinkelių transportas, keleivių vežimas, kokybės kriterijai, AHP metodas, svarbumas, konkordancija.

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 the country's economy and nonproductive sectors, the fifth level; and TS impact on the country's GAV (Gross Added Value), the sixth level. Properties and factors influencing on the results and parameters of interaction have been systematized. Levels and properties of interaction have been analyzed as well. To evaluate the importance of interaction levels to the parameters of the transportation process, the method of Analytic Hierarchy Process (AHP) has been recommended. Santrauka Kiekvienos šalies ūkio ir negamybinės veiklos sektoriai negalėtų funkcionuoti be transporto sistemos. Išanalizavus mokslo darbus, skirtus atskirų transporto sistemos elementų sąveikai tirti, nustatyta, kad visas sąveikos rūšis vienijančio modelio nėra. Transporto sistemą sudaro materialūs (fiziniai) transporto objektai: eismo dalyviai ir kroviniai, kuriuos reikia vežti, transportavimo procesas ir veiklos reguliavimas. Pateikta transporto sistemos klasifikavimo pagal sistemiškai pasirinktus kriterijus schema, rodanti, kad oficialiuose dokumentuose dažnai vienu metu taikomi keli kriterijai. Pateiktas originalus transporto sistemos fizinių elementų sąveikos modelis, kuriame išskirti šeši sąveikos lygmenys. Modelis tinka visoms transporto rūšims. Pirmajam lygmeniui priskirta transporto elementų autosąveika, antrajam—transporto sistemos elementų tarpusavio sąveika, trečiajam—transporto sistemos elementų sąveika su išorine aplinka, ketvirtajam—transporto rūšių sąveika, penktajam—transporto sistemos sąveika su šalies ūkio ir negamybinės veiklos sektoriais, šeštajam—transporto sistemos įtaka šalies bendrajai pridėtinei vertei. Susisteminti sąveikos požymiai ir veiksniai, turintys įtakos fizinės sąveikos rezultatui ir jos parametrams. Išanalizuoti sąveikos lygmenys ir jos savybės. Sąveikos lygmenų prioritetui (svarbai) transportavimo proceso parametrams vertinti pasiūlyta taikyti Analytic Hierarchy Process (AHP) metodą, kurio pagrindą sudaro elementų porinio lyginimo matrica. Skaičiuojamajame pavyzdyje nustačius transporto sistemos elementų skirtingų lygmenų sąveikos svorį kelių transporto saugumui įrodytas AHP metodo tinkamumas transporto sistemos elementų sąveikai modeliuoti. Резюме Различные секторы хозяйственной и непроизводственной деятельности любого государства не могли бы функционировать без транспортной системы. На основе анализа научных трудов, посвященных исследованиям взаимодействия отдельных элементов транспортной системы, установлено, что не существует модели, объединяющей все виды и уровни взаимодействий. Транспортная система включает в себя разные материальные (физические) объекты. Это участники движения и грузы, которые необходимо перевозить, транспортный процесс и регулирование деятельности. Приведена схема классификации транспортной системы по системным подходам, установленным критериям, свидетельствующая о том, что зачастую в официальных документах одновременно применяется несколько критериев. Предложена оригинальная модель взаимодействия физических элементов транспортной системы, в которой выделены 6 уровней взаимодействий. Модель пригодна для всех видов транспорта. Первый уровень присвоен взаимодействию транспортных элементов, т. е «внутреннему» взаимодействию однородных материальных элементов транспортной системы, второй – взаимодействию материальных составляющих элементов транспортной системы, третий – взаимодействию материальных составляющих элементов транспорта с внешней, окружающей средой, четвертый – взаимодействию различных видов транспорта, пятый – взаимодействию транспортной системы с секторами хозяйственной и непроизводственной деятельности страны, шестой – влиянию взаимодействия транспортной системы c сектором экономики, а также влиянию непроизводственной деятельности страны на экономику (внутренний валовый продукт), предопределяющую прожиточный уровень населения. В модель включено влияние науки и исследований. Систематизированы признаки и факторы, оказывающие влияние на результат физического взаимодействия элементов транспортной системы и ее параметры. Выполнен анализ уровней взаимодействия и его свойств. Для определения приоритета (весомости) различных отдельных уровней взаимодействия на параметры процесса транспортирования предлагается применять метод анализа иерархий (Analytic Hierarchy Process), основу которого составляет матрица попарного сравнения элементов. На примере расчета весомости различных уровней взаимодействия элементов транспортной системы, влияющих на безопасность дорожного транспорта, доказана пригодность -метода AHP для моделирования взаимодействия элементов транспортной системы. Reikšminiai žodžiai: transportas, elementai, sąveika, modelis, sistema, išorinė aplinka, AHP metodas Ключевые слова: транспорт, элементы, взаимодействие, модель, система, внешняя окружающая среда, метод анализа иерархий