Hasil untuk "Highway engineering. Roads and pavements"

Jakub Majewski, Piotr Malepszak

Abstract: This article analyzes the prospects and scenarios for the development of high-speed rail in Poland against the backdrop of experiences from other European countries. Despite early investments, such as the Central Rail Line from the 1970s, Poland remains behind in the process of European high-speed infrastructure. A significant change in this regard was the introduction of speeds of 160 km/h and subsequently the introduction of Pendolino trains. This improved the quality of transport; however, their full potential (250 km/h) is still not fully utilized. Planned investments, including the modernization of the Central Rail Line and the construction of the "Y" high-speed line (Warsaw–Łódź–Wrocław–Poznań), aim to significantly increase train speeds and enhance the competitiveness of rail transport. An analysis of the experiences of France, Germany, Italy, and Spain indicates positive economic and environmental effects of implementing high-speed rail systems, while also highlighting different planning and operational models of individual HSR (High-Speed Rail) systems. This allows for the assessment of individual models in terms of the applicability of their elements in the implementation and development program of the high-speed rail system in Poland. Keywords: High-speed rail; Rail infrastructure; Investments

Shiva Kumar Govindaraju, Nitin Gopanahally Chandrasekharaiah, Gurudeep Ganesh et al.

This research examined the feasibility of incorporating electric arc furnace (EAF) slag and waste plastic into stone matrix asphalt (SMA) mixtures. With annual global production of over 70 million tons of EAF slag and 300 million tons of plastic waste, repurposing these materials could yield substantial environmental benefits. The research evaluated SMA mixtures with EAF slag as aggregate replacement and waste plastic as a binder modifier. The research aimed to develop sustainable SMA formulations while promoting recycling of industrial byproducts. Laboratory experiments were conducted to evaluate mix design characteristics, drain-down potential, abrasion resistance, rutting resistance, moisture susceptibility, fatigue performance, and stiffness of modified SMA mixtures. The addition of waste plastic, ranging from 4%, 6%, 8% and 12% by weight of bitumen, demonstrated significant improvements in key properties. Results showed that waste plastic reduced the optimum binder content and increased voids in the mineral aggregate. EAF slag mixtures demonstrated improved drain-down characteristics and moisture susceptibility. Both rutting resistance and fatigue life increased significantly with waste plastic content, with EAF slag mixtures consistently outperforming those made with conventional aggregates. Ultrasonic pulse velocity tests indicated higher stiffness in modified mixtures. The optimal waste plastic content was determined to be 8% by weight of bitumen. Statistical analysis confirmed significant effects of both EAF slag and waste plastic on multiple performance parameters. These findings highlight the potential of incorporating industrial byproducts into SMA mixtures to achieve high-performance road construction solutions, offering a viable pathway for addressing global waste management challenges.

Arslan Qayyum Khan, Syed Ghulam Muhammad, Ali Raza et al.

This study evaluates the performance of advanced machine learning (ML) models in predicting the mechanical properties of eco-friendly self-compacting concrete (SCC), with a focus on compressive strength, V-funnel time, L-box ratio, and slump flow. The motivation for this study stems from the increasing need to optimize concrete mix designs while minimizing environmental impact and reducing the reliance on costly physical testing. Six ML models-backpropagation neural network (BPNN), random forest regression (RFR), K-nearest neighbors (KNN), stacking, bagging, and eXtreme gradient boosting (XGBoost)-were trained and validated using a comprehensive dataset of 239 mix design parameters. The models' predictive accuracies were assessed using the coefficient of determination, mean squared error, root mean squared error, and mean absolute error. XGBoost consistently outperformed other models, achieving the coefficient of determination values of 0.999, 0.933, and 0.935 for compressive strength in the training, validation, and testing datasets, respectively. Sensitivity analysis revealed that cement, silica fume, coarse aggregate, and superplasticizer positively influenced compressive strength, while water content had a negative impact. These findings highlight the potential of ML models, particularly XGBoost and RFR, in optimizing SCC mix designs, reducing reliance on physical testing, and enhancing sustainability in construction. The application of these models can lead to more efficient and eco-friendly concrete mix designs, benefiting real-world construction projects by improving quality control and reducing costs.

Alina Korchevska, Denis Shpin, Liudmila Nahrebelna et al.

Introduction. Horizontal road marking is an important element of road safety, which provides orientation of road users on the road. Road markings can increase the capacity of the road by more than 20 % and reduce the number of road accidents. Problem. Road markings must remain clearly visible both during the day and at night, and in adverse weather conditions, such as rain or fog. In satisfactory condition, markings usually provide adequate nighttime visibility on dry surfaces, but their effectiveness is significantly reduce. To improve the light reflection in the dark, microspheres of retroreflective glass are used in the marking. These elements function effectively on dry asphalt, however, in the presence of a water film, light can be partially reflected in the opposite direction, which reduces the brightness of the marking or causes optical distortions. Reduced visibility of markings on wet surfaces is a common problem that affects road safety. Objective. To analyze the requirements of different countries for road markings on wet surfaces to check the sufficiency to establish compliance with the requirements of DSTU 2587 necessary to ensure the quality of markings. Materials and Methods. Analysis of regulatory documents of different countries regarding the requirements for road markings on wet surfaces.

Alina Yunak, Anton Zheltobriukh, Ivan Kopynets et al.

Introduction. In Ukraine, the procedure for designing asphalt mixtures includes selecting the ratio of aggregates, determining the optimal bitumen content, testing the asphalt concrete with the selected bitumen content, and refining the mix desgn if necessary. A similar procedure is used in the United States, the European Union, Australia, and other countries. However, the key difference lies in the equipment used to prepare asphalt concrete samples. Problem Statement. In recent years, the method of asphalt concrete sample preparation in Ukraine using compression compaction has been subject to criticism. The main concerns include the lack of a clearly defined loading rate, potential crushing of mineral aggregate grains during sample preparation, and the fact that the compaction achieved in laboratory conditions is often lower than that in road pavement layers. These factors may lead to suboptimal asphalt mixture design and premature defect formation during operation. This necessitates research to optimize laboratory compaction of asphalt concrete mixtures, particularly through the use of a gyratory compactor. Objective. To implement a gyratory compactor for laboratory compaction of coarse-grained asphalt mixtures.

Mykola Ananiev

Introduction. Rail transport has been and remains the main mode for cargo transportation in Ukraine. At the same time, due to the military aggression against Ukraine, air transport, which was used for most international passenger transportation, has not been available since February 2022. Shipping remains partially closed due to the aggressor's blockade of Ukrainian seaports and canals. This makes it important to ensure the sustainable functioning of alternative land routes to the EU, as well as the organization of cargo and passenger transportation in cooperation with European countries. Problem Statement. Given the different gauge size from most EU neighboring countries, projects aimed at increasing throughput and freight capacity with the European Union by developing a 1 435 mm gauge railway network (Euro gauge) in Ukraine, as well as organizing multimodal terminals at the border and infrastructure for transferring bogies are of particular importance. Purpose. Analysis of initiatives and priorities for the development of the 1 435 mm gauge (European gauge) railway network in Ukraine.

Doni Rinaldi Basri Basri, Elsa Eka Putri, Bayu Martanto Adji et al.

Provinsi Riau memiliki tanah gambut dengan daya dukung rendah, dengan kedalaman hingga mencapai 16 meter. Apabila dilakukan pembangunan jalan di atas tanah gambut maka dapat mempercepat terjadinya penurunan dan kerusakan pada jalan. Perkembangan teknologi timbunan ringan dengan menggunakan mortar busa dapat dimanfaatkan sebagai pengganti lapisan pondasi (base). Pasir lokal pada Desa Teratak Buluh Kabupaten Kampar memiliki gradasi lebih halus dari gradasi standar, namun diharapkan dapat dipergunakan dalam pembuatan mortar busa sebagai pengganti lapisan pondasi pada perkerasan jalan di atas tanah gambut yang ada di Provinsi Riau. Tujuan penelitian adalah untuk menganalisis kuat tekan dan berat isi mortar busa dengan gradasi awal pasir terhadap gradasi standar. Metode penelitian dilakukan secara kualitatif dengan melakukan eksperimental di laboratorium sesuai dengan pedoman perancangan campuran material ringan dengan mortar busa untuk konstruksi jalan. Sebagai pengganti lapisan pondasi, berat volume < 0,8 t/m3 dan kuat tekan >2000 kPa. Kesimpulan diperoleh gradasi pasir teratak buluh lebih halus dari pada gradasi PUSJATAN, pasir ini bisa digunakan untuk pembuatan mortar busa dengan kuat tekan > 2000 kPA dengan berat isi 0,90 t/m3.

Authors Alina Yunak, Ivan Kopynets, Oksana Sokolova

Introduction. One of the most important characteristics of asphalt concrete that characterizes its properties is the elasticity modulus. The elasticity modulus of asphalt concrete is used in the design of pavement structures to calculate its permissible elastic deflection, under the condition of shear resistance of the working subgrade layer and the layers of non-cohesive materials, as well as bending tensile strength. Problem statement. Today, the calculated value of the elasticity modulus of asphalt concrete is taken in accordance with Handbook No. 2 «Design Characteristics of Asphalt Concrete» [2]. In this Handbook, the calculated value of the elasticity modulus of asphalt concrete is given depending on the bitumen grade, temperature, type of asphalt mixture, and time of load action. Numerical design values of the elasticity modulus of asphalt concrete are provided only for asphalt concrete type B; for other types of asphalt concrete, it is proposed to reduce or increase the design value of the elasticity modulus by the value that depends on the type of asphalt concrete and temperature. Since 2020, a new standard on technical requirements for bitumen has been in force in Ukraine, which brings bitumen grades in line with the European classification [4]. At the same time, in the Handbook No. 2 [2], the calculated value of the elasticity modulus of asphalt concrete is given in accordance with the previous bitumen grades, which necessitates their adjustment.

Bohdan Zelenskyi, Inessa Rutkovska, Olena Slavinska et al.

Introduction. Assessment of the qualitative condition of road bridges is a complex process that involves the analysis of physical and functional deterioration of structures. Physical deterioration is associated with deterioration of materials and loss of strength of elements, while functional deterioration is manifested in a decrease in the bearing capacity and deformability of the bridge. Problems. To determine the level of wear, a comprehensive method is used, including visual inspection, calculation estimates and experimental studies. In addition, a differentiated method is used, which allows comparing actual values with design values and drawing conclusions about the quality of individual elements and the structure as a whole. Objective. The expert method is an important addition to other methods of assessing the technical condition of bridges. Materials and Methods. It allows to take into account factors that are difficult to formalize and provides a comprehensive understanding of the condition of the structure. However, in order to obtain reliable results, it is necessary to carefully approach the formation of an expert group and the organization of the assessment process. Results. Assessment of the qualitative condition of bridges is critical to ensuring the safety of their effective operation. The qualimetric model offers a detailed and structured approach to assessing the physical deterioration of a bridge by dividing the entire structure into key elements and evaluating each of them according to various parameters and provides a comprehensive assessment of its condition.

Jacek Nowicki

Abstract: The use of hydrogen technologies is the most effective way to decarbonise long- haul transport - including commercial aviation. Two leading technical solutions introducing hydrogen into the propulsion systems of civil airliners are the use of fuel cells generating electricity to power electric motors for propeller propulsion, and turboprop and turbojet/turbofan engines using hydrogen fuel. More than a dozen companies and research centers around the world are carrying out works aimed at introducing hydrogen-powered communication aircraft into operation by 2035. Keywords: Aviation hydrogen technologies; Hydrogen aviation propulsion; Aviation electric propulsion; Fuel cells; Turboprop engines; Turbofan engines

Mykhailo Korniev

Introduction. Bridge DBN V.1.2-15:2009 «Loadings and impacts» is the document that raised the level of calculated traffic loadings on bridges and bring their values closer to the values of LM1 model of Eurocodes. But the characteristic loadings were remained at the old level, which violated the principles of reliability calculations, according to which the characteristic loadings should deviate from the average values by 5 standards at least. Problem statement. Estimated vehicle loadings of the AK model in DBN B.1.2-15:2009 in compare with LM1 model of Eurocode EN 1991-2 and the track model according to US AASHTO LRFD standards shows that there is a certain balance between them. The calculated loading according to the standards of Ukraine occupies an intermediate position between the standards of Europe and the United States. However, the level of characteristic loadings is almost twice lower in compare with in Eurocode. This is a significant drawback of DBN, because it reduces the level of reliability of calculations based on the second group of limit states.

Przemysław Brona, Adam Dąbrowski, Beata Piwowar

Abstract: The article presents the most important aspects of changes in the training and examination system for candidates for train drivers and train drivers, which will enter into force on January 1, 2023. First, the system currently in force in Poland is characterized and its basic disadvantages are indicated. Then, the scope of legal changes resulting from the amendment to the Act on Rail Transport is described, which will lead to the separation of training and examination processes, and, as a result, to improvement of the efficiency of these processes. The article also presents the scope of activities of the currently built Center for Examination and Monitoring of Train Drivers, which will function at The Office of Rail Transport and will be equipped with modern simulators. Keywords: Train driver; Training; Examination; Simulator

Dmytro Pivtoratskyi, Olha Dubova, Volodymyr Kaskiv

Introduction. One of the main causes of deformation on roads is the deconsolidation of soils of the working layer of the subgrade and the non-strengthened lower layers of road structures. To eliminate this problem the technology of soil strengthening is used. Soil strengthened by the binder is an artificial monolithic material, which is formed by hardening the soil, after treatment with the binder, due to the physical and/or chemical processes after compaction and curing under specified conditions, and satisfies the standard requirements for physical and technical indicators in the project intermediate terms. Soil mass stabilizer is a modifier of the soil particles surface, which affects the value of the hydrogen index in which the soil structure is formed, improves the physical and mechanical properties of the soil. Problem statement. During road construction and repairing, the problem of unsatisfactory bearing capacity of subgrade appears quite often. For rational solving of this problem, the possibility of strengthening or stabilizing the soil is considered. Purpose. The purpose of the work is the analysis of laboratory tests data and determination of the effectiveness of soil stabilizers use. Materials and method. Analysis of information sources on foreign and domestic experience of soil stabilizers use. Results. The result of the work is established physical and mechanical properties of the soil with and without the use of stabilizer. Conclusions. When using soil stabilizers, the key to the effective use of capital investments in the construction or reconstruction of roads by increasing the strength of the road structure we see in a clear understanding of the functional orientation of the additive, the choice of appropriate technology, the selection of the optimal mix design and type of stabilizer. The research carried out at the State Enterprise «DerzhdorNDI» on the expediency of using a polymer-based stabilizer for the complex strengthening of sandy loam to increase the strength of the embankment base soil found that the obtained proportions of additive and cement have achieved a positive result.

Łukasz Semkło, Agata Wróblewska

Abstract: The parameter defined as the coefficient of friction is one of the basic parameters that are responsible for the characteristics of the surface on which vehicles (cars, aircraft) travel. The coefficient of friction is very important as it is responsible for the safety and relia- bility of the pavement. The paper below presents general issues concerning the friction force and its influence on the movement of aircraft on airport pavements. The requirements for the assessment of the friction coefficient were also discussed. Based on the results of tests carried out at four airports, an analysis of the decrease in the value of the friction coefficient was per- formed. Keywords: Friction; Runway; ASFT

Zhang Chao, Wang Jie, Qiao Jiangang

The analysis of the spatial and temporal distribution law of pavement friction coefficients at tunnel entrances of mountainous highways is conducive to improving the safety of traffic at tunnel entrances in winter, and the combined prediction process of pavement friction coefficients at tunnel entrances of mountainous highways is proposed. The data of road surface temperature and humidity were collected in the field, and a prediction model of road surface temperature and humidity at the tunnel entrance was constructed using a bi-directional long and short term memory neural network (Bi-LSTM) model. Combined with a large number of indoor friction coefficient tests, the relationship between friction coefficient and temperature and humidity under different pavement conditions was established, and then the Equal Friction Coefficient Line (EFCL) of the tunnel entrance pavement was proposed to determine the distribution range of friction coefficient under the ice and snow environment at the tunnel entrance and the unfavorable spatial and temporal area of traffic safety with $\text{EFCL} < 0.4$. The results show that the spatial and temporal regions with $\text{EFCL} < 0.4$ are the tunnel entrance regions with clear sky periods of 5-7 h, −200 m to +50 m from the cave entrance and periods of 23-9 h, −25 m to +25 m from the cave entrance. The snow time period is 23∼4 h for the whole area of the tunnel entrance, providing data support for the tunnel entrance traffic safety and security technology.

E. R. Akhtyamov, UralNIistrom, Alexander Y. Dedyukhin et al.

The article discusses the results of implementation of the laboratory information management system (LIMS) U-LAB, developed by the UralNIIstrom Institute and tested in the regional road sector. The system of quality control of asphalt-concrete road surfaces, road pavement structures and road-building materials in the construction, repair and maintenance of highways is presented, the role of independent laboratory control, engineering and scientifictechnical support, supervision of design decisions is defined. The content and advantages of using the U-LAB LIMS for organizing and improving the efficiency of laboratory quality control of highways and building materials, improving interaction between road management bodies, contractors, design and scientific organizations involved in road works are described. The program interface is shown, the results and technical and economic indicators of the implementation and operation of LIMS in the UralNIIstrom test center in 2020 are presented.

O. Anikeeva, A. Ivahnenko, M. Storublev

Highways are the most important component of country's economic development. They are a complex of engineering structures that are subject to various kinds of deformations during operation. The causes of premature defects are outdated technologies, poor quality materials, high traffic loads, and weather conditions. On average, after 2–3 years of the new road operation, pits, overflows, potholes, cracks, rutting occur on asphalt concrete pavement, its presence worsens the traffic conditions on the road and violates the unimpeded passage of cars. To extend the life cycle of a transport object, there are preventive measures that prevent the destruction of road surfaces. Such activities include regular maintenance and repair work. One of the effective measures is the use of road impregnation materials (RIM). Road-impregnation materials are used in case of need to prevent aging of the organic binder in the composition of asphalt concrete in the coating, as well as to reduce the impact of external factors. In this article, the influence of the basis of the impregnating material of two manufacturers on the indicators of the properties of asphalt concrete of various degrees of destruction is investigated. Among the considered impregnating compositions, solvent-based road impregnation materials proved to be the most effective. It has been established that the abrasive effect on samples of asphalt concrete significantly reduces the effectiveness of impregnating materials, especially based on bitumen emulsion.

B. Azarov

The author considers the accuracy of multiple measuring the excess obtained during the work on geodesic support of the definition of certain road sections surface wear-and-tear degree in the Altai region. Basing on these results in nine cycles for seven federal highways’ sections, the accuracy of determining the excess between the reference points and the roadway points was evaluated. It is noted that at performing the work, the standard deviation measuring excess at the station can serve as a criterion for accuracy. Various options of its calculation are considered, depending on which measurements are taken in joint processing. The analysis of the root-mean-square errors obtained as a result of parsing different variants is performed. It is also noted that the data gathered during the research should be considered at engineering-technical leveling as well as in the process of measuring the values of seasonal road base points’ changes in automobile road sections which are surveyed to define the deterioration rate of the road pavement.

Andrejs Podkoritovs, Dmitrijs Serdjuks, Vadims Goremikins et al.

Behaviour of the inverted triangular truss, which is widely used as a bridge girder, was investigated analytically and experimentally. Cold-formed square hollow cross-sections of steel grade S355J2H with dimensions 80 mm × 4 mm, 90 mm × 4 mm and 40 mm × 4 mm were selected for the top and bottom chords and bracing elements of the truss with 12.56 m span, correspondingly. Five FEM models were developed using software Dlubal RFEM. The main specific feature of the models is the difference in modelling of joint behaviour considering plastic behaviour and stiffness of truss connections. It was shown that the FE model of the truss where the members were modelled by the truss type finite elements and the joints modelled by the shell type ones allows predicting behaviour of the truss with precision of up to 3.9%. It was shown that precision of the suggested FEM model grows 4.36 to 4.62 times in comparison with the traditional FEM models where the members were modelled by the truss finite elements with the pinned and rigid joints in case of plastic joint behaviour. Precision of the suggested FEM model is identical to that of the traditional FEM models regarding the case of elastic joint behaviour.

Szmagliński, Jacek

The paper describes problems occurring during travelling by trams over curves. It was determined that stong jerks occur as a result of the lack of analysis of kinematic parameters on curves and changes in the construction scheme of trams. A proposal for a computational methodology has been given. Calculations of kinematic parameters were carried out for typical geometric layouts in accordance with the Polish Guidelines.