The present paper substantiates urgency of studies on early deterioration of pavement layers and on reasons entailing it. The aim was to investigate static and dynamic loads imposed on a road surface ...by vehicles in order to detect signs of early deterioration of pavement and understand its reasons. Certain tasks were set: to define diagnostic capacity for performing test works on road surface with the use of static and dynamic loading equipment; to carry out an elastic modulus analysis on the basis of static and dynamic loading tests performed; to assess strength properties of flexible pavement. The paper describes methods for determining strength properties of a road surface with the use of special static and dynamic loading equipment. The authors provide data on diagnostic capacity of tests of a pavement performed with the use of special testing equipment. The paper gives a list of potentials, advantages and fundamental features of the following units of equipment: apparatus for plate bearing tests, Dina-3M, UDN-NK, Dynatest apparatus. The main parameters of equipment for dynamic loading tests are provided. The results of both dynamic and static loading tests performed in Saint Petersburg and the Leningrad region are given. Deflection bowls and elastic modulus were determined. Coefficients of the dynamic elastic modulus being reduced to the static one were calculated. Strength properties of flexible pavement were assessed.
During the recent years, car makers intensively develop and implement systems of active, passive, post-accident, environmental and fire safety of road vehicles. These devices and systems improve the ...safety but complicate the design and increase the cost of maintaining the vehicle in the operative condition. That is why there is necessity to evaluate the road vehicle as to the efficiency of operation regarding a number of complex safety characteristics. Solution to this task should be based on evaluating the (relative) importance of particular values for every characteristic considered to be a separate criterion of safety. In order to do that, we need to formulate a system of values for safety characteristics of the road vehicle and develop a formalized mechanism to assess the relative importance of every criterion in the form of a method for multi-criteria evaluation of the complex characteristic of road vehicle safety.
The paper contains results of studies of changes in performance of plant machinery and vehicles during operation: non-failure operating time, costs, revenue, profit and cost efficiency. It is shown ...that decrease of non-failure operating time and increase of operating costs can be described by the exponential law. Mathematical models based on changes of performance parameters were developed in order to determine optimum service life of machinery according to economic criteria. The paper describes application of an information system for collection and processing of data necessary for models. Application of the developed method for determining of optimum service life would contribute to rational formation of machinery fleet.
Russia ranks first among countries of Europe and North America as to fatal road accidents per 100,000 residents. The share of road accidents in the Russian Federation due to operation of ...malfunctioning vehicles is 3.6% of the total number of road accidents, and it still remains high as compared to European countries. Therefore, relevance of the study is conditioned by the need to take urgent measures for reduction of the number of road accidents occurring due to poor technical condition of vehicles. Reduction of the number of road accidents for this reason is possible by enhancing the operational reliability of vehicles.
The purpose of the study is to develop a method for quantitative assessment of the vehicle reliability influence on traffic safety. The method is based on an analysis of the vehicle as a complex technical system, its structural elements having the greatest impact on traffic safety. The method includes calculation of time between failures and time for restoration of subsystems, assemblies and parts, as well as calculation of the probability of failure-free operation. As a result of method application, recommendations to replacement intervals of vehicle elements depending on the required probability of failure-free operation are provided.
Key findings are the following. The described method allows assessing the actual reliability of a vehicle and contribution of its individual elements to it. In order to control the reliability by maintenance tools, the method allows determining replacement intervals for vehicle elements depending on the required probability of failure-free operation.
This paper analyzes the role and methods of diagnosing actor’s accident abilities, applied to traffic safety. We highlight the fact that safety equipment and measures (both industrial and ...traffic-related) provide only partial protection against various hazards, as the most critical hazard source for any person is the person themself, for a variety of reasons, including safety violations, which begin to occur when people grow accustomed to dangerous conditions and situations. By studying the internal (psychological) motivations behind reckless driving and other dangerous behavior, we gain additional opportunities for ensuring the safety of traffic and other high-risk activities. This paper analyzes studies by Russian and foreign authors that touched upon the factors of high-risk driving, and reviews the possible means of adjusting human behavior in dangerous situations by prompting a fear response. We also examine Russian researchers’ approaches to diagnosing accident abilities, which we define as the abilities to escape a dangerous situation safely; this includes having a sense of danger. We adopt S.A. Eliseev’s approach, wherein a person with a sense of danger is able to: balance between success and safety; avoid risks in conditions that they are accustomed to; not become accustomed to danger; find a safe approach to an unsafe situation; anticipate various actions and sources of danger; detect even subtle danger signs and warnings; learn from previous experiences with danger; predict and avoid danger. Our study includes several possible ways of diagnosing accident abilities: simulation experiments and surveys. We describe the process of designing and testing a survey form aimed at assessing a person’s sense of danger. The study includes a discussion of the future prospects of using this method.
The paper addresses the issues of improving the performance of the handling and transport complex at a mining enterprise. It presents statistical estimates for the general standard reliability of the ...transport system, which should correspond to similar indicators of subsystems of equipment, machinery, etc. We studied the operation of a rock mass transportation system used in open-pit mines. The handling and transport complex includes dump trucks of various capacities and a single-bucket elevator. The process of rock mass excavation and transportation depends on weather and climatic conditions. Among the factors that affect the transport system performance, the following can be distinguished: air temperature, snowdrifts, gas accumulation in the pits, and, as a result, reduction of the visibility range, leading to a decrease in the average speed of vehicles. The mathematical models of transportation are based on the well-known methods of forming excavator and truck fleets. To calculate the reliability of the transport system in the pit, it is necessary to have data on the probability of no-failure operation and the mean time between failures for each vehicle. Information about the state of the vehicles was obtained based on the results of statistical analysis. During optimization calculations, the following restrictions and assumptions were accepted: the limit state of a vehicle was determined by the mileage of 250,000 km; the distribution of the fleet vehicles’ mileage was subject to the Weibull law with the variation factor approximately equal to 1. In this case, the distribution of the mean time between failures can be considered exponential. Analysis of statistical data on the operational reliability of vehicles showed that random failures prevail. When simulating the operation of handling and transport complexes, it is necessary to take into account the parametric and technological connection between individual machines operating within these systems. The developed methodology for justification of the level of equipment adaptation to the operating conditions is aimed at improving the reliability of handling and transport complexes involved in mining production.
Until recently, the digitalization of distributed process facilities in the oil and gas industry implied equipping the facility with a digital constant power supply control system. At present, ...increased requirements for industrial safety as well as technical, administrative, and economic difficulties in external power supply for the distributed facilities of the gas transport system have led to the need to create digital remote control systems capable of operating on power sources using renewable resources (solar or wind energy). The paper describes theoretical studies and presents the results of the technical implementation of new remote control systems for gas well clusters, single wells, single and twin gas pipeline branches. The current development level of intelligent process control systems makes it possible to accumulate large volumes of primary information for subsequent analysis and solution of control problems both in normal and emergency situations. In this case, a high probability of correctness or the greatest effectiveness of the decisions made is ensured. The paper considers the process of gas transport via a trunk line, carried out by a gas transport enterprise, and the process gas gathering via an inter-field line of a gas field, carried out by a unit of a gas production enterprise, as examples, for which a Decision Support System (DSS) is created.
The article addresses relevant issues of vehicle traffic management when using operational and technical monitoring systems in the field of traffic safety assurance. The authors provide a rationale ...for promising directions of traffic management system improvement using automated traffic enforcement facilities to record traffic violations. The operation of a system of technical means of monitoring is modeled. A method to evaluate the efficiency of traffic enforcement system management is proposed. It allows us to determine the implementation degree of management functions assigned to the monitoring system in the field of traffic safety assurance. A stochastic model is developed to evaluate the performance of departments that ensure traffic monitoring using automated traffic enforcement facilities. The results of the study conducted include the developed model as well as a method and algorithm for optimizing the structure of the system managing operational and technical means of vehicle traffic monitoring.
This paper covers the results of monitoring active safety systems during vehicle operation.
The analysis of the existing diagnostic methods for active safety systems in operation shows that on-board ...diagnostics of active safety systems does not cover the entire list of possible malfunctions.
It is also worth considering that the electric drive systems of active safety systems are an integral part of the vehicle’s braking system influencing traffic safety during operation.
This issue can be resolved by supplementing the monitoring process with an additional diagnostics complex. This monitoring system receives data on the working processes of the vehicle automated systems’ components in real time.
An important difference from existing diagnostic systems is the ability to determine the exact malfunction of a vehicle’s automated system component, as well as to establish the cause of the malfunction, allowing the system to reduce the possibility of a recurring malfunction and improve traffic safety.
Coupled together with a data-sharing interface, this monitoring system enables the creation of the active vehicle’s digital twin. We provide an example of how this simulation technology, based on a fusion of virtual and physical elements, helps study vehicle performance in complex, multi-factor operation modes.
This diagnostic system, used in combination with a bench chassis model, makes it possible to adapt the system if the manufacturer adjusts the vehicle’s automated system design, thereby simplifying the process of further verification of the digital twin.
As automation grows more and more widespread, the use of such systems becomes more and more relevant.
The article substantiates the concept of quantitative assessment of knowledge uncertainty in accident reconstruction tasks based on application of mathematical tools of the fuzzy set theory allowing ...considering an uncertainty of initial data caused for instance by varying resistance to the motion of investigated objects at the apex stages of the contact–separation processes. The application of the mathematical tools of the fuzzy set theory can substantially expand the potential of applying the methodology to the automobile and technical expertise and provide the enhancement of authenticity and improve the accuracy of making conclusions about the accident reconstruction results.
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