Railway Construction Research Articles

Evaluation of Steel Slag as a Sustainable Alternative Aggregate for Railway Ballast: A Shakedown Theory-Based Approach

Recent advancements in railway construction have emphasized environmental sustainability, integrating considerations of environmental impact into the planning and execution of infrastructure projects to reduce costs and mitigate adverse effects. This study investigates the use of steel slag as a sustainable alternative for railway ballast, grounded in shakedown theory. The characterization of the aggregates was performed in accordance with NBR 5564 and AREMA standards, confirming that the material meets most requirements. The mechanical behavior of the ballast was analyzed under cyclic loading conditions, assessing permanent deformation and the material’s ability to achieve stability (shakedown). Triaxial tests with repeated loading simulated real railway conditions, applying vertical stresses up to 600 kPa and confining pressures ranging from 35 to 200 kPa. The results indicate that steel slag aggregates exhibited promising performance, with seven specimens achieving stable deformation levels, characterized by residual deformations of less than 2.5 mm. Notably, these specimens approached deformations on the order of 10−7, indicating stability under cyclic loading. Furthermore, a comparative analysis of shakedown criteria proposed by various authors revealed variations in limits for granular materials, enhancing the understanding of steel slag aggregate behavior. The experimental results were validated through numerical simulations conducted with Systrain software 2.0, which simulated a loading condition of 32.5 tons per axle, confirming the observations with maximum principal stresses ranging from 166 to 184 kPa in the ballast. The analysis showed that steel slag aggregates can withstand stress levels higher than those of granodiorite, reinforcing their viability as a sustainable alternative for railway ballast.

Knowledge graph-driven mountain railway alignment optimization integrating karst hazard assessment

Karst hazard is a considerable threat that should be considered in railway alignment design for mountainous regions with dense water systems. Nevertheless, alignment design principles in karst regions have not been systematically studied. Moreover, a quantitative karst hazard assessment model is currently lacking for automated alignment optimization. To solve the above problems, based on the analyses of karst inducing factors and hazard representation, the railway alignment design principles in karst regions are summarized through an event tree. A highly-coupled knowledge graph (called KaRAD-KG) modeling method is proposed. Then, a bi-objective alignment optimization model considering railway construction cost and karst hazard (mainly including hazard components of synclinal karst, anticlinal karst and karst depression) is constructed. To solve the optimization model, a knowledge-driven distance transform algorithm incorporating a karst hazard assessment method and a multicriteria tournament decision method is customized. Finally, the application in a real-world case indicates that the proposed method can generate an alignment which reduces construction cost by 3.39 % and karst hazard by 18.73 % compared to the best manually-designed alternative, which verifies the effectiveness of this method for assisting actual railway alignment design in a karst-dense mountainous region.

Understanding China’s infrastructure activities in Africa through artistic practice and exhibition

The infrastructure-led development model initiated by China under the Belt and Road Initiative (BRI) has faced domestic and international challenges. By focusing on a national travelling art exhibition featuring Chinese railway construction in Africa in 2023, this paper examines the role that curatorial and exhibition practices can play in (re)shaping public geopolitical understandings of China-Africa relations. Exhibiting over 200 artworks collected from both China and Africa, this art programme not only forms a nuanced, personal and storied narrative of China’s overseas development work in Africa but also tactically responds to current internal and external criticism of the Chinese government’s global ambitions channelled through the BRI. This work extends the ongoing interest geographers have at the intersection of the visual arts and critical geopolitics.

JUSTIFICATION OF THE FEASIBILITY OF RECONSTRUCTING ONE TRACK OF A DOUBLE-TRACK SECTION TO THE EUROPEAN STANDARD GAUGE (1435 mm)

The article systematizes scientific developments concerning the design and reconstruction of railway lines to the European track gauge of 1435 mm. Drawing on the experience of European countries, the study investigates the conditions under which it is feasible to implement a project solution involving the reconstruction of a double-track section into two single-track sections with different gauges: one track remains at 1520 mm, while the other is converted to 1435 mm. The research was conducted using graph-analytical modeling methods. The methodology involves the use of a developed mathematical model that allows for evaluating different scenarios of line capacity using transportation mastery graphs. The study forecasts transportation volumes under pessimistic, rational, and optimistic scenarios, under which the reconstruction of a double-track section into two single-track sections with gauges of 1435 mm and 1520 mm may be justified. A scientific approach is proposed, enabling the evaluation of various capacity scenarios for two single-track sections with gauges of 1520 mm (existing) and 1435 mm (reconstructed), using graph-analytical modeling methods. Based on the results of domestic and foreign scientific developments, potential solutions are outlined for the construction of European standard railways in Ukraine, considering existing infrastructure, geopolitical, topographical, and other conditions. The advantages of this solution include cost savings (as one track does not need to be rebuilt), maintaining connections with countries that use the 1520 mm gauge, and the ability to organize train movements with different track gauges.

Regional subsidence monitoring and prediction along high-speed railways based on PS-InSAR and LSTM

The rapid construction of high-speed railways in China has forced more and more routes to pass through slow subsidence zones caused by groundwater extraction or underground mining. It is crucial to carry out deformation monitoring and prediction those areas along high-speed railways to ensure the safe operation. Twenty-nine periods of Sentinel-1A data between Taiyuan South Station and Taigu East Station were first processed using the PS-InSAR technique, and the ground subsidence sequences at ten typical points were selected. Then the Variational modal decomposition (VMD) was combined with the Adaptive Boosting Algorithm (AdaBoost), and the VMD-LSTMAda-LSTMAda model was constructed by combining the long short-term memory (LSTM) model for the prediction of regional ground subsidence along the high-speed railway. The results show that the cumulative subsidence within the 200 m buffer of the line centreline is − 37.58 − 89.19 mm, and the annual average subsidence rate is − 26.57 − 82.63 mm/y. The proposed model can reduce the complexity of the deformation sequence and combines with AdaBoost to improve the prediction accuracy of the LSTM model. It performs well in terms of RMSE, MAE, MAPE, and R2 at the two feature points (3703: RMSE = 0.82 mm, MAE = 0.25 mm, MAPE = 6.31%, and R2 = 0.94; 522: RMSE = 1.32 mm, MAE = 0.46 mm, MAPE = 4.92%, R2 = 0.95). The model improves the accuracy of regional subsidence prediction along the high-speed railway.

Impact of typical environments in China's western mountainous areas on the durability of railway concrete: a review

PurposeThis study aims to analyze the impact mechanism of typical environments in China's western mountainous areas on the durability of railway concrete and propose measures to improve durability.Design/methodology/approachWith the continuous promotion of infrastructure construction, the focus of China's railway construction has gradually shifted to the western region. The four typical environments of large temperature differences, strong winds and dryness, high cold and low air pressure unique to the western mountainous areas of China have adverse effects on the durability of typical railway structure concrete (bridges, ballastless tracks and tunnels). This study identified the characteristics of four typical environments in the western mountainous areas of China through on-site research. The impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research; Finally, a strategy for improving the durability of railway concrete suitable for the western mountainous areas of China was proposed.FindingsThe daily temperature difference in the western mountainous areas of China is more than twice that of the plain region, which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless tracks. It will result in cracking. The wind speed in the western plateau region is about 2.5 to 3 times that of the plain region, and the average annual rainfall is only 1/5 of that in the plain region. The drying effect on the surface of casting concrete will significantly accelerate its cracking process, leading to serious durability problems. The environmental temperature in the western mountainous areas of China is generally low, and there are more freeze-thaw cycles, which will increase the risk of freeze-thaw damage to railway concrete. The environmental air pressure in the western plateau region is only 60% of that in the plain region. The moisture inside the concrete is more likely to diffuse into the surrounding environment under the pressure difference, resulting in greater water loss and shrinkage deformation of the concrete in the plateau region. The above four issues will collectively lead to the rapid deterioration of concrete durability in the western plateau region. The corresponding durability improvement suggestions from theoretical research, new technology development and standard system was proposed in this paper.Originality/valueThe research can provide the mechanism of durability degradation of railway concrete in the western mountainous areas of China and corresponding improvement strategies.

Mathematical Modeling of the Floating Sleeper Phenomenon Supported by Field Measurements

This article aims to provide an accurate mathematical model with the minimum number of degrees of freedom for describing the floating sleeper phenomenon. This was accomplished using mathematical modeling supported by extensive field measurements of the railway track. Although the observed phenomenon is very complex, the simplified single degree of freedom (SDOF) mathematical model proved accurate enough for its characterization. The progression of the deterioration of the railway track was successfully correlated to changes in the maximal dynamic factor for different types of pulse loading. The results of the presented study might enable the enhanced construction and maintenance of railroads, particularly in karst areas.

Energy-saving cruise control method for heavy-duty transport vehicle based on pump-valve coordinated drive

In order to realize the dual-goal of the improvement in the cruise performance and fuel economy of the heavy-duty transport vehicle (HDTV) for the transfer of the prefabricated box-girder in the construction of high-speed railway, a pump-valve parallel coordinated drive scheme is designed on the basis of the hydrostatic drive system of the HDTV, which combines the load-sensing valve control system and hydrostatic pump control system. Furthermore, the pump-valve coordinated controller (PVC) is also proposed to ensure the cooperation of the two systems, which adopts power following control strategy to control engine speed, the pump and motor displacement respectively, thus achieving the rough adjustment of the cruise velocity. The linear quadratic regulator (LQR) based on the full-state closed-loop feedback is introduced in PVC to control the proportional direction-valve (EPDV) and compensate for the velocity errors, thus realizing the fine adjustment of cruise velocity. A semi-physical experimental test-platform for the HDTV is established to conduct contrast tests between the rule-based controller (RBC) and the proposed PVC under different operating conditions. The results indicate that the PVC effectively reduces the velocity error, the total error is decreased by 80.6% and that of the maximum error is 43.4% under empty-load conditions, and under heavy load conditions, the total error is lowered by 82.1% and that of the maximum error is 46.8%. Moreover, the PVC also brings down the fuel consumption rate of the HDTV, with a maximum reduction of 27.6% and a minimum of 11.4%.

Influence of collapsible shape of Loess Foundation on high-speed railway subgrade under train vibration loading

Collapsible loess has special sensitivity to water, and its engineering mechanical properties deteriorate significantly after immersion in water, causing the foundation to sink, which seriously threatens the safety and stability of the high-speed railway subgrade under train vibration loading. Studying this effect is essential to prevent and control the disasters of high-speed railway subgrades. In this study, a model with the function of simulating foundation settlement is established to conduct disaster testing of high railway subgrade under train vibration loading. The results indicate that when different foundation shapes are settled, the surface of the subgrade under static load is gradually settled in a short time, and the settlement value of the track surface is lower than that of the corresponding subgrade surface. Under train vibration load, the maximum dynamic settlement occurs at the middle of the subgrade slope, which is smaller than the corresponding settlement under static load. The number of stabilization times required from different monitoring positions on the subgrade surface is different under different excitation forces, and the number of stabilization times required is more in the middle of the subgrade slope and the slope shoulder. The influence of train speed on subgrade has a critical respond speed that increases with increasing vibration times. There are horizontal, vertical and 45° angle cracks in the middle of subgrade slope. It is qualitatively assessed that the slope of the high-speed railway subgrade in the collapsible loess area is unstable under the effect of train load. The data and rules provided in this document provide some reference values for the construction of a high-speed railway in the collapsible loess area.

Map of anthropogenic soil disturbance in Russia

Soils play an important role in maintaining the sustainability of the biosphere, as well as providing food, clothing and the basis for human life on Earth. In the process of irrational land use, soils are often degraded and sometimes completely destroyed. But, inventory of destroyed soils on a systematic basis is still not conducted in any country of the world. In Russia, traditional soil maps do not reflect the destroyed soils either. We have made an attempt to create the first map of the country, which shows soils destroyed as a result of directed anthropogenic impact. The map shows areas where soil cover was destroyed as a result of construction of buildings, structures, roads and railroads, quarries and embankments during mining. The crowdsourcing database OpenStreetMap was used as the main source of information, as well as the results of visual interpretation of disturbed soils using GoogleEarthTM satellite data. The data on disturbed soils were aggregated to soil-geographical sections of the Unified State Register of Soil Resources of Russia (scale 1 : 2500000) (UGRSR). The map is presented in GIS format (shapefile). The map contains information on the area and share of disturbed soils, as well as the type of impact that resulted in disturbance.

Impact of high-speed railway construction on freight capacity on sections of existing railways- A case on the Yangtze River Delta

The construction of high-speed railway (HSR) can effectively release the freight capacity of existing railways. By analyzing the influencing factors of passengers’ travel choices, the Utility Function and Logit model are adopted to calculate the utility and passenger flow split rate, and get the passenger flow of the existing railways after the diversion of the newly-built HSR. The passenger flow allocation model is established based on User Equilibrium, and improved Frank-Wolfe (FW) algorithm is applied to solve it, and obtain the passenger capacity of the sections on existing railways. Based on the deduction coefficient method, the passenger capacity is deducted from total capacity to get the freight capacity of each section on existing railways after release. Finally, take the railway channel in the Yangtze River Delta as a case, the results show that after the construction of the HSR, the freight capacity of sections on existing railways in the Yangtze River Delta is released to varying degrees. The freight capacity of Hefei-Wuhu section will be released the most, which is 19.5 pairs of trains, while that of Shanghai-Jiaxing section is the least, which is only 3.5 pairs, following by Wenzhou-Jinhua and Hangzhou-Ningbo sections, which are 4 pairs. Therefore, the construction of HSR should be accompanied by focusing on sections with less released freight capacity to enhance the overall capacity of the regional railway network.

Design and Construction of Automatic Railway Crossing Gate Control Using Proximity and Infrared Sensors Based on Omron CP1E E30-SDRA PLC

Railway crossing gates are one of the railway infrastructure facilities. Currently, there are still many problems, especially in traffic accidents. The cause of traffic accidents at railway crossings generally occurs due to the lack of facilities and infrastructure (rail crossing gates) and negligence of guards in carrying out their duties. Therefore, it is necessary to design an automatic railway crossing gate. The prototype of the automatic railway crossing controller uses proximity and infrared sensors to detect the arrival and departure of trains. When the infrared or proximity sensor detects the arrival of a train, the Programmable Logic Controller (PLC) activates Pulse Width Modulation (PWM), buzzer, and Light Emitting Diode (LED), so that the crossing motor goes down. After the crossing touches the limit switch, the motor stops and the buzzer and Light Emitting Diode (LED) remain on. The infrared or proximity sensor detects the departure of the train so that it reverses the motor so that the crossing goes up, then turns off the buzzer and Light Emitting Diode (LED). In this way, it is hoped that this design can be used to increase the efficiency of the system's operational costs and optimize the railway crossing system and is expected to reduce the number of traffic accidents at railway crossings.

The Dynamics of the Construction of the Jakarta-Yogyakarta Railroad throughthe Banyumas Karesidenan (1914-1917)

This research was conducted with the aim of complementing the study of the topic of the history of civil engineering technology from the colonial period which explains thedevelopment of rail-based transportation networks, as well as the trial and error of new technology trials at that time. In this research, it is expected to obtain a basic and detailed explanation of the planning, location determination, and construction process. In addition, the research that took place on the Cirebon-Kroya railway line concentrated on the Notog-Kebasen segment reviewed the development of the railway network in Java which was closely related to the transportation revolution in the application of new technology in Java, including the construction system of tunnels, roads, and bridges (mentioned as wisdom buildings), located in the Notog-Kebasen area. The explanation in this research is presented in a chronological, systematic, and qualitative analysis, to examine the topic of the history of civil engineering technology in the construction of the railroad network, including the wisdom building. The construction of the Cirebon-Kroya railway refers to the law of December 31, 1912 Stbl. 32/(1913), in which the 75 km Cirebon-Margasari section was opened on July 1, 1916, the 51 km Kroya-Margasari section was opened on July 1, 1916, and the 32 km Patuguran-Margasari section was opened on January 1, 1907.

A Study on the China-Laos Railway’s Economic and Strategic Significance

To analyze the economic and strategic significance of the China-Laos Railway, this paper will examine its impact on both China and Laos from their respective perspectives during the construction of the railway. The results show that the China-Laos Railway will significantly improve transportation efficiency in Laos, promoting rapid economic and social progress and development; The China-Laos Railway will be fostering economic development and cooperation among the countries and regions along the railway; Simultaneously, the successful construction of the China-Laos Railway has showcased China's prowess in high-speed railway construction to the international community, setting a positive example for China's future expansion into new high-speed railway markets; The successful construction of the China-Laos Railway, along with its later plans to connect ports on the west coast of Thailand and Malaysia, will facilitate the opening of new Indian Ocean ports in China's southwest, ensuring the secure supply of energy transportation; Moreover, The China-Laos Railway will also bolster China's geopolitical influence in ASEAN, deepen economic and political cooperation between China and ASEAN countries, and play a significant role in advancing the implementation of China's Belt and Road Initiative.

Does transportation infrastructure contribute to urban entrepreneurship? Evidence from the high-speed railway in China

High-speed railways have a profound impact on entrepreneurship. Adopted China's city panel data, we use a time-varying DID model to estimate the influence of the high-speed railways on urban entrepreneurship and study its mechanism. The analysis results reveal that high-speed railways have improved the entrepreneurial vitality of cities. The mechanism test suggests that high-speed railway promotes entrepreneurship activities by accelerating human capital flow, strengthening producer services agglomeration, and promoting market integration. A range of robustness tests including a parallel trend test, placebo test, and PSM-DID model are used to ensure the reliability of the empirical results. Heterogeneity analysis and spatial analysis are used to deepen the research. Heterogeneity analysis reveals that high-speed railway construction is likely to motivate entrepreneurship in eastern cities, big cities, and cities with high-level business environments. The spatial analysis results show that the opening of the high-speed railways promotes the entrepreneurial level of surrounding cities. The research results help to evaluate the economic benefits of high-speed railway network expansion, and provide decision-making references for stimulating urban entrepreneurship.

Federalising Socialism Without Doctrine

The Australian Constitution is only partly ‘liberal’ (securing political and economic liberties); another part is ‘socialist without doctrine’ (empowering governments to own and operate vast public capital, while providing social insurance in a market economy). That mixture is common in modern advanced economies but was anomalous in the Anglophone constitutional tradition in 1901. Legislative power over ‘old age and invalid pensions’, ‘railway construction’ and ‘conciliation and arbitration for the prevention and settlement of industrial disputes’ was an accepted part of the incipient Federal scheme but repugnant to Anglophone constitutional orthodoxy of the 19th century. The integration of ‘colonial socialism’ into the Constitution created one of the longest-standing puzzles in Australian jurisprudence, the Surplus Revenue Case of 1908, and laid the foundations for federal dominance of the Australian economy. Understanding the enduring impact of colonial socialism in Australian constitutionalism sheds light on how Australia’s distinctive political economy grew within a ‘Washminster’ system of government. It also provides principled guidance for future policy challenges that may require expansion of state involvement in the economy.

On the 130th anniversary of the Krasnoyarsk Rail Transport Institute — branch of Irkutsk State Transport University

In 2024 Krasnoyarsk Rail Transport Institute — branch of Irkutsk State Transport University turns 130 years. The history of its establishment is connected with the rapid development of railway transport in Russia and the construction of a new railway in Siberia. The article presents an outline of the 130-year history formation and development of the oldest educational institution, founded in 1894 as the First Siberian Technical Railway School. The main stages of the university’s formation are determined, achievements in the professional training of specialists in the railway industry, its contribution to the socio-economic development of the country are considered.

Cossacks in the Conditions of Frontier Modernization (on the example of the Far East in the late 19th – early 20th centuries)

Historically, the contacts between the Cossacks and the Chinese population were established and their particular strengthening occurred during the construction of the Chinese-Eastern Railway between 1897 and 1903. The imperial authorities devised a plan to establish the Sungurian Cossack army, which was to be augmented by the Cossacks dispatched to protect the ‘KVZhD’. These troops were to comprise the descendants of Albazin and the local population. In the context of the present circumstances, the Cossacks in the peripheral Ussuri Territory and Manchuria served as the frontiers of the system of relations with the local Chinese and Korean populations, as well as the modernizing transformation of the region. As the most mobile and passionate segment of the population, the Cossacks played a pivotal role in the socio-economic and cultural transformation of the region. Their extensive involvement in the agrarian economy and their diverse socio-class and ethno-confessional composition contributed to the diversification of the regional mosaic. During this historical period, the Cossacks served as the driving force of the Russian exploration of the Far Eastern space. Moreover, they facilitated the militarization of the newly developed territories. The format of the study permits presenting a set of relations risen along the Center–Far Eastern Cossacks axis. The objectives of this paper is to ascertain the nature of this relationship within the system and to study the dissemination of the experience of the Cossack self-government system to neighboring regions, including the process of Japanese colonization of the island of Hokkaido. The research findings indicate the efficacy of applying the Cossack administrative and economic management experience to the Far East and Manchuria, as well as in adjacent regions, such as Hokkaido. The article is intended for Cossack specialists and sinologists.

Economic and environmental assessment of the Korea urban railway and its greenhouse gas mitigation potential

Railways can simultaneously transport large quantities of freight and passengers, making them energy-efficient and economical modes of transportation. Changing the materials that constitute a significant portion of rail track systems can help mitigate climate change. Gravel and concrete trackbed methods are commonly employed in railway construction. This study proposes the utilization of the asphalt concrete trackbed method, which is currently being researched and developed in South Korea, in addition to traditional gravel and cement concrete methods, and presents its economic feasibility and environmental benefits. The asphalt concrete trackbed method, which has already been implemented in regions such as China, Australia, and Europe, can also be applied in other areas. This study analyzed the carbon emissions and economic feasibility in the construction, usage, and disposal stages of cement concrete and asphalt concrete trackbeds. Previous research on carbon emissions analysis has faced challenges in applying geographical and climatic, as well as energy sources, to individual cases in the context of construction in Korea. Using the Korean Life Cycle Inventory database, this study indicated that asphalt concrete exhibits approximately 2.65-times lower carbon emissions than cement concrete. In Korea, railway construction involves 1,998 tons of asphalt concrete mixture, 1,820 cubic meters of cement concrete, and 59 tons of rebar per kilometer. Furthermore, the asphalt concrete trackbed method shows potential cost savings of approximately 29,000 EUR when converted to the 2021 EAU value. Thus, asphalt concrete trackbeds not only provide environmental benefits, they are also economically viable. However, further research is required to establish precise standards for on-site construction. This study is expected to provide foundational data for promoting the widespread adoption of asphalt concrete trackbeds in areas that produce asphalt concrete.

Thermal enhancement of targeted cooling thermosyphon array applied to the embankment–bridge transition section of the Qinghai–Tibet railway in warm permafrost

Permafrost degradation in the embankment–bridge transition section (EBTS) along the Qinghai–Tibet Railway has led to extensive damage to bridge structures, posing a serious threat to railway safety. With the ongoing global warming, reinforcing the affected EBTS to ensure long-term stability remains a pressing challenge. To address this issue, this study proposes a targeted cooling thermosyphon array (TCTA) approach utilising variable inclination evaporator (VIE) thermosyphons. The effectiveness of the VIE thermosyphon was evaluated through an in-situ test. Meanwhile, a three-dimensional numerical model was employed to analyse the overall cooling effect, long-term performance and thermal enhancement provided by the TCTA approach. The findings indicated that the VIE thermosyphon exhibited excellent cooling performance and maintained uniform wall temperature, with the lowest wall temperature reaching −15 °C. Within one year of implementation, a cold core of −2 °C formed at the centre of the foundation, and the permafrost table was uplifted by approximately 3 m, showcasing its potential to rapidly enhance the thermal stability of in-service EBTS in permafrost. With prolonged operation, the cold accumulative effect of this approach gradually becomes apparent, and the range of the low-temperature cores expands. This method effectively reinforces the thermal stability of in-service EBTS and is well-suited for future railway construction in warm permafrost amidst the challenges of climate change.