Ensuring safety is a key condition for organizing rail transportation. All technical aspects of traffic should be subject to regulatory requirements aimed at reducing the likelihood of an emergency. Since there are many factors affecting the safety of train traffic, the task of minimizing the risks of accidents should be considered in an integrated system.
The concept of transportation processes
To understand the principles of the organization and functioning of the security system in the railway infrastructure, it is necessary to determine the features of the train movement process. This transport system differs from others in that its participants, even within the framework of one process, are separated at a great distance - this also applies to technological service centers, personnel, and the facility directly. That is, a key factor in servicing transportation activities involves the implementation of many technical actions, which increases the complexity of coordination and management.
This specificity explains the introduction of the concepts of heterogeneous system performance. It characterizes the functioning of the infrastructure as a whole, despite the fact that one of the elements may remain inoperative. Therefore, in ensuring the safety of train traffic, an important role is played by communication between the individual elements of the overall service system. Timely notification also helps prevent accidents and promptly take measures to eliminate the detected malfunction.
Another characteristic of the railway transportation process is related to the current state of train movement, which may qualify as dangerous or non-dangerous. The definition of this condition also uses the concept of operability and the compliance of an object with the established requirements of regulatory and technical documentation. Moreover, as an object, not only the composition can be considered, but also the railway transport system as a whole as affecting all objects operating within its base.
Train Safety Analysis
This analysis is carried out in order to determine the array of data on the actual level of security at a particular object of the railway transport infrastructure. Moreover, the scale of the object can vary from one unit of composition to the railway system as a whole. The information collected is required to develop a system for ensuring and maintaining the safety of train traffic, which is achieved by assessing the adequacy of the measures that are currently being taken to prevent emergency threats. Based on the analysis, priority tasks are set with a reasonable allocation of resources for their implementation.
As the main parameters that are evaluated during the inspection of the object, the following can be distinguished:
- Statistical data obtained during the process of performance testing.
- Loss risk indicators.
- Risk indicators of economic damage.
- Traffic safety indicators.
- Safe working hours.
- Parameters for performing various types of repair operations.
- Maintenance performance parameters - scheduled and overhaul.
- Types of dangerous traffic.
- Environmental characteristics in the area of ββoperation of the facility.
Based on the data obtained, an analysis processing plan is developed and a report is prepared. The analysis procedure itself, which is carried out in order to create a train safety system, involves several steps:
- Setting the scope of analysis and research boundaries.
- Organization of supervision of the analysis.
- Determination of destabilizing conditions.
- Conducting a point analysis of destabilizing conditions.
- Fixation of dangerous conditions during the movement of trains.
- Point analysis of dangerous traffic conditions.
- Drawing up a list with damaging factors arising at the time of dangerous conditions.
- Setting the types and characteristics of losses that the object suffers due to the influence of damage factors.
- Analysis of losses from damage factors.
- Calculation of the risk of specific losses.
- Documentation of processed data.
- Verification of the results.
Transportation Safety Improvement Methods
Technological approaches to improving the safety of railway transport operation are based on three principles:
- Reducing the likelihood of dangerous equipment failures or personnel errors.
- Reducing the number of types of technical failures or errors caused by the human factor.
- Reducing the rate of parry of technical failures or personnel errors.
To comply with each of these principles, certain methods are used. In particular, to ensure the safety of train traffic during operation, the technical infrastructure is regularly monitored with a check on the strength of the element base. To increase the strength potential, both means of increasing mechanical resistance and methods of increasing the electrical security of devices are used. Moreover, it should be noted that the design and production processes at manufacturing plants where materials are selected have a significant impact on the operational durability of structures and elements.
The principles for improving safety by increasing the failure rate are mainly reduced to two methods:
- Identification of a dangerous failure.
- Conclusion of the device from the operational state to protection.
Technological approaches in train safety measures with the withdrawal of faulty funds vary in degree of automation. An example of a non-automated method is the case when, during a routine inspection, an employee detects a break in the rails, after which he introduces a ban on movement in a particular section. Conversely, automatic blocking of the same rails is possible if a rail circuit with a controller unit is provided in the local infrastructure.
Personnel activities as an element of the security system
Reducing the intensity of errors due to the human factor is no less important than minimizing technical failures. In most cases, train traffic safety violations occur due to interrelated influence factors, when personnel make a mistake that entails technical damage. Also, equipment failures occur due to oversight of serving workers.
Work in the direction of reducing personnel errors is carried out according to criteria of a physiological, psychological and medical nature. Already at the stages of staff training, in addition to laying the necessary knowledge base, processes of developing practical skills and abilities that increase the efficiency of work are organized. Particular attention is paid to the psychophysiological qualities of workers. For example, for the driver, such personal qualities as concentration of attention, extroversion of the psyche, ability for sensory coordination and emotional stability are brought to the forefront. Theoretical training is more important for the train safety auditor. The list of his responsibilities includes monitoring the implementation of technical rules and compliance with organizational instructions. Therefore, it is important for the auditor to have knowledge of regulatory legal acts and an understanding of the general processes of train movement and the system for the production of shunting work measures.
Stage guard for work
Work activities on the stage is a regular travel action that requires the systematic organization of a special mode of operation of the site. At the time of work, the hauls and stations should be provided with means of technical stopping of trains, as well as signaling devices, warning about the need to reduce speed. Guards should be installed regardless of whether the train is scheduled to arrive or not.
The installation parameters of fences and, in particular, the distance from the immediate place of work is determined by the guiding descent and high-speed mode, operating on a particular stage. For example, safety requirements for train traffic in sections with a speed mode of up to 80 km / h require that fences with signaling devices be installed at a distance of about 800-1000 m. If the permissible speed regime reaches 160 km / h, then the distance of placing fences increases to 2150 m.
Of considerable importance in determining the methods of organizing fences are the parameters of the working platform itself. The format of its arrangement may differ in the size and coverage of the paths. Safety requirements for train traffic during track work on sites with a length of 200 m or more require the installation of red signals at a distance of 50 m from the boundaries of events on both sides of the train. Moreover, in the process of carrying out work actions, signals should be controlled by the site manager.
Safety during work at the station
Permission to carry out work activities at the station track locations is issued by the station duty officer or an employee who performs the functions of sending and receiving trains at a specific section.
The main task of workers complying with train safety regulations, in this case, will be to remove obstacles on the tracks that could threaten the processes of movement or work. If an obstacle is detected at the station, the track foreman or road foreman will be required to immediately enclose the area with warning signals. After that, a record should be made in the inspection journal about the closure of traffic at the place of detection of the obstacle or about the speed limit.
In the conditions of fencing of station tracks due to an obstacle, traffic on a specific section is terminated. From this moment, in order to maintain the safety of train traffic, measures are being taken to prevent the train from entering the obstacle zone or carrying out track work. The time for the closure of the site and the installation parameters of the signals are assigned by the station manager. At the same time, depending on the circumstances, he can coordinate his actions with the track leader, electrician or senior mechanic responsible for signaling, centralization and blocking of tracks. In any case, according to the results of the actions taken, a record is left in the inspection journal stating the type, time and place of work to close the site.
Microprocessor Security Systems
This is a modern approach to the organization of railway management, in which multichannel methods for reducing dangerous failures are used. The principle of operation of microprocessor control is to detect dangerous infrastructure elements in the process of complex comparison of signals from a wide array of observed control points. The input information on the operating parameters of the functional units is not processed separately within the framework of a specific function, but taking into account adjacent elements of the system. For example, the state of a signaling device or warning device is evaluated together with the operating parameters from the communication equipment and the mechanical unit, which is activated in parallel with the issuance of a command to the signaling equipment.
In addition, microprocessor equipment to ensure the safety of train traffic during operation also compares arrays of intermediate data, collecting statistics on various indicators. Thus, elements of machine learning are realized, due to which the efficiency of premature detection of technical and operational units that can fail in the near future is increased. The disadvantages of microprocessor multi-channel security systems include the high cost of technical implementation and the demanding qualifications of the operator.
Introduction of intelligent video surveillance systems
In the railway infrastructure, video surveillance systems are being actively introduced today, which are becoming one of the basic elements of integrated security. Among the main tasks of intelligent video surveillance systems, it is worth noting the implementation of visual control of the target site or facility, in which the so-called "security events" are highlighted. During the monitoring process, changes in the working environment are recorded, according to which the prerequisites for a dangerous failure can be established. Moreover, in modern systems for ensuring the safety of train traffic, high-tech video equipment is used, which is noticeably ahead of traditional systems of this type both in functionality and in structural implementation. Firstly, the entire infrastructure with cameras, monitors, storage and data conversion bases is built on a digital communication basis. Secondly, the intelligence aspect of the equipment is determined by the availability of the so-called video analytics tools, which, using specialized software and graphic video processing systems, allows emergency situations to be recorded without operator intervention.
The capabilities of video analytics today are organically integrated into the overall set of measures to ensure the safety of train traffic, realizing the following tasks:
- Detection of third-party objects through motion sensors.
- Tracking of target objects from the positions of several cameras, provided with special video stream processing algorithms.
- Marking of objects according to predefined signs of size and shape.
- Identification and recognition of objects.
- Prediction of the behavior of the observed object.
Accident loss mitigation techniques
Minimization of damage in accidents and train crashes is achieved by reducing the degree of impact of damaging factors. Unlike methods for reducing the dangerous conditions of operating equipment, methods for reducing losses are already operating in the conditions of a realized threat. Universal methods of this kind include measures aimed at compensating the inertial forces of goods and passengers in collisions. Technically, in this case, means of artificial damping of inertia should be used, which is ensured by structural elements in the device of wagons. For example, high-speed trains are equipped with elastic elements in the end parts. For the same purpose, the vestibule is made in the form of an accordion.
In the instructions for the safety of train traffic, much attention is paid to the regulation of high-speed modes, as well as to ways to prevent trains from entering certain zones in case of loss of control. But if the movement could not be stopped, the consequences of an imminent accident will depend entirely on the strength of the collision, which is especially critical for freight cars and tanks. What loss reduction methods are used in this aspect of train operation? Again, at the structural level, special inter-car ligaments are used, which act as damping and absorbing elements. It can be elastomeric, hydro-rubber and spring-friction units, which smoothly reduce the speed of the composition that has lost control. Also, in the infrastructure of the routes, the use of dead ends is assumed, which serve as barriers or the same speed compensators.
Conclusion
Technologies and organizational concepts for ensuring safety on the railway are constantly being improved along with an increase in the dynamic qualities of vehicles. In Russia, the most acute problems in this area include handling crossings as elements of a common railway infrastructure. According to experts of the largest Russian carrier Russian Railways, train safety largely depends on the discipline of motorists. To prevent collision threats at level crossings, the company annually carries out comprehensive measures to improve warning and protective systems. In addition to traditional reinforced concrete flooring and rubber products, automatic signaling systems have been used more and more often recently, which allow restricting movement on the basis of sensory control readings.