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This study aims to analyze the factors, evaluation techniques of the durability of existing railway engineering.

China has built a railway network of over 150,000 km. Ensuring the safety of the existing railway engineering is of great significance for maintaining normal railway operation order. However, railway engineering is a strip structure that crosses multiple complex environments. And railway engineering will withstand high-frequency impact loads from trains. The above factors have led to differences in the deterioration characteristics and maintenance strategies of railway engineering compared to conventional concrete structures. Therefore, it is very important to analyze the key factors that affect the durability of railway structures and propose technologies for durability evaluation.

The factors that affect the durability and reliability of railway engineering are mainly divided into three categories: material factors, environmental factors and load factors. Among them, material factors also include influencing factors, such as raw materials, mix proportions and so on. Environmental factors vary depending on the service environment of railway engineering, and the durability and deterioration of concrete have different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapid detection methods for five common diseases in railway engineering are also proposed in this paper. These methods can quickly evaluate the durability of existing railway engineering concrete.

The research can provide some new evaluation techniques and methods for the durability of existing railway engineering.

The mega railway infrastructure projects are faced with complex environments and multi-level management challenges. Thus, the mega railway infrastructure project management system not only needs to focus on its composition, but also needs to consider changes and impacts of internal and external environment.

This study attempts to introduce the concept of dissipative structure from the perspective of complexity theory and constructs a positive entropy and negentropy flow index system for mega railway infrastructure project management system in order to analyze the factors of management system more deeply. The Brusselator model is used to construct the structure of the mega railway infrastructure project management system, and the entropy method is used to calculate the positive entropy and negentropy values to verify whether the management system is a dissipative structure.

A plateau railway project in China was used as an example for an empirical study, not only its own characteristics are analyzed, but also the role of constraints and facilitation of the internal and external environment. Based on the research results, several effective suggestions are put forward to improve the stability and work efficiency of mega railway infrastructure project management system.

This study demonstrates that mega railway infrastructure project management system has the characteristics of dissipative structure. It can provide theoretical support for the development of mega railway infrastructure project management system from disorderly state to orderly state.

Under the dual pressure of resources and environment, many countries have focused on the role of railways in promoting low-carbon development of integrated transportation and of even the whole society. This paper aims to provide a comprehensive study on methods to improve railway energy efficiency in other national railways and achievements made by China’s railways in the past practice, and then to propose ways in which in the future China’s railways could rationally select the path of improving energy efficiency regarding the needs of the nation's ever-shifting development and carry out the re-engineering for mechanism innovation in energy conservation and emission reduction process.

This paper first studies other national railways that have tried to promote the improvement of railway energy efficiency by the ways of technology, management and structural reconstruction to reduce energy consumption and carbon emissions. Among them, the effect of structural energy conservation and emission reduction has become more prominent. It has become the main energy conservation and emission reduction measure adopted by foreign railway sectors. The practice of energy conservation and emission reduction of railways in various countries has tended to shift from a technical level to a structural one.

Key aspects in improving energy efficiency include re-optimization of energy structure, re-innovation of energy-saving technologies and optimization of transportation organization. Path selection includes continuing to promote electrified railway construction, increasing the use of new and renewable energy sources, and promoting the reform of railway transportation organizations.

This paper provides further challenges and research directions in the proposed area and has referential value for the methodologies, approaches for practice in a Chinese context. To achieve the expected goals, relevant supporting policies and measures need to be formulated, including actively guiding integrated transportation toward railway-oriented development, promoting innovation in energy-saving and emission reduction mechanisms and strengthening policy incentives, focusing on improving the energy efficiency of railways through market behavior. At the same time, it is necessary to pay attention to new phenomena in the railway industry for track and analysis.

The entire sector of railway transport is in a state of flux in Europe as deregulation and structural changes are affecting the traditional transport mode. Even though the aim has been to increase railway freight competition, markets have changed only slightly, and the market shares of incumbent railway companies are remaining high. Some EU countries have not attracted any new entrants, which is also the current situation in Finland. This paper aims to assess how the Finnish railway freight competition develops and to analyze different views on railway transport policy.

This research work analyses a Delphi questionnaire directed at 52 Finnish experts in this branch. Responses on the questionnaire were gathered during year 2005 (competition in Finland in railway freight started 2007) within two rounds with appropriate amount of response rate. Respondents were from the public and private sectors, actors working closely with railway transports and logistics. With an expert profiling matrix, three different railway transport policy viewpoint groups are identified, and character descriptions for these are constructed.

Based on a qualitative expert profiling analysis, it is argued that there exist three different argument types in Finnish railway transport policy. The authors have constructed character descriptions for each group based on material collected by the Delphi technique. They conclude that the policy definitions have followed the views of the moderate group and the realization of the deregulation process has been slow, even though a great amount of competition was expected.

The research work is limited to the Finnish railway freight transport market, where development of competition on rails has been sluggish. To further confirm the used methodology, and the identified railway freight competition policy group types, the research work should be repeated in some other country, and particularly in an environment where competition has shown activity immediately after deregulation.

The research represents methodology to foresee the future development of deregulated industries, and especially in the transportation sector. The paper's approach can be used to divide stakeholders into groups and to make policy analysis. The problem with to‐be‐deregulated industry is often lack of competition, new actors and governmental actions, and therefore the used Delphi technique offers potential to gather empirical material before any activity has actually started in the observed industry.

The aim of this paper is to compare the railway and internet revolutions. What do they have in common and what is different between them, considering the 150‐year time difference in their occurrence? As time passes, can internet developers learn something from the railway industry?

The two industries have a lot of common. Both railways and the internet represent national infrastructures that cannot be managed just based on business management principles. As both are concerned with traffic, either that of physical goods or of messages, the two industries also seem to have a lot in technical terms when one takes a sufficiently abstract point of view. The main message is that in the long term, the railway revolution vanished and the industry turned into a low profit/interest field. The internet might follow the same path.

The paper in its current form is based on a literature review only. Its quality could be improved with a detailed empirical study. Other similar infrastructure‐type industries could also be involved.

There are several things that could be improved in the management of the internet, but they are large‐scale issues needing co‐operation between the many stakeholders in the internet. Examples are those of avoiding the digital divide and catering for critical “last mile” connections, as well as managing the diversity of different standards.

As far as the author knows this is the first paper of its kind comparing these two industries. The message is that more cross‐industrial studies need to be performed. Also, the message of the paper – that the internet might turn into a low‐interest business in the long run – has not been discussed sufficiently.

Explore the development trend of chemically-improved soil in railway engineering.

In this paper, the technical standards home and abroad were analyzed. Laboratory test, field test and monitoring were carried out.

The performance design system of the chemically-improved soil should be established.

On the basis of the performance design, the test methods and standards for various properties of chemically-improved soil should be established to evaluate the improvement effect and control the engineering quality.

This study aims to analyze the development direction of train speed, density and weight in China.

The development of China's railway in the past 40 years can be divided into 3 stages. At the stage of potential tapping and capacity expansion, it is important to improve the train weight and density by upgrading the existing lines, and improving transportation capacity rapidly. At the stage of railway speed increase, the first priority is to increase train speed, reduce the travel time of passenger train, and synchronously take into account the increase of train density and weight. At the stage of developing high-speed railway, train speed, density and weight are co-developing on demand.

The train speed of high-speed railway will be 400 km h⁻¹, the interval time of train tracking will be 3 min, and the traffic density will be more than 190 pairs per day. The running speed of high-speed freight EMU will reach 200 km h⁻¹ and above. The maximum speed of passenger train on mixed passenger and freight railway can reach 200 km h⁻¹. The minimum interval time of train tracking can be compressed to 5 min. The freight train weight of 850 m series arrival-departure track railway can be increased to 4,500–5,000 t and that of 1,050 m series to 5,500–6,400 t. EMU trains should gradually replace ordinary passenger trains to improve the quality of railway passenger service. Small formation trains will operate more in intercity railway, suburban railway and short-distance passenger transportation.

The research can provide new connotations and requirements of railway train speed, density and weight in the new railway stage.

This paper aims to deal with the formulation of the technological principle for precise positioning using global navigation satellite systems (GNSS) in railway engineering during construction and maintenance of a railway line and its spatial position. Solution of optimal route is based on finding the shortest Hamiltonian path in the graph method with additional conditions in nodes.

The core of the algorithm is a dynamic data structure which is based on events list. The optimization of field measurement solves the time demands and brings economic effectiveness.

The technology enables to determine the precise position with absolute difference limit from 10 to 15 mm within GNSS CZEPOS permanent network in the territory of Czech Republic.

Technology is the result of applied research.

This technology innovates the current procedure of geodetic control network determination used by Railway Infrastructure Administration (state organization) in Czech Republic.

The event means measurement at a given track point and time for a specified duration of observation. The algorithm was realized in Borland Delphi. The optimization of field measurement solves its time demands and increases economic effectiveness. The technology enables precise position determination with absolute difference limit from 10 to 15 mm within GNSS CZEPOS permanent network in the territory of Czech Republic. It has been verified in field selected electrified and non-electrified railway lines.

As the infrastructure of the railway, the rail could sink or deform to different degrees due to the impact of train operation or the geological changing force for years, which will lead to the possibility that the facilities on both sides of the rail invade the rail clearance and bring hidden dangers to the safe operation of the train. The purpose of this paper is to design the gauge to measure the clearance parameters of rail.

Aiming at the problem, the gauge for clearance measurement was designed based on a combination measurement method in this paper. It consists of the measurement box and the rail measurement vehicle, which integrates a laser displacement sensor, inclination sensor, gauge sensor and mileage sensor. The measurement box was placed outside the rail vehicle. Through the design of a hardware circuit and software system, the movement measurement of the clearance parameters was realized.

In this paper, the measurement equations of horizontal distance and vertical height were established, the optimal solutions of the structural parameters in the equations were obtained by Levenberg–Marquardt method, then the parameter calibration problem was also solved.

The gauge has high precision; its measurement uncertainty reaches 1.27 mm. The gauge has manual and automatic working modes, which are convenient to operate and have practical popularization value.