Certificate of state registration of a computer program

Scientists fr om the SPbGASU Department of Land Transport and Technological Machines (LTTM) have developed a program for calculating reliability indicators of construction machines in operation. They received the certificate for the computer program No. 2023665148 dated 12.07.2023.

The program was developed with financial support for the implementation of research work by scientific and pedagogical workers from the SPbGASU Division for Scientific Work in 2023.

The team of authors included professors Sergey Repin and Sergey Evtyukov, dean of the Faculty of Automobile and Road Building Andrey Zazykin and assistant Vasily Chechuev. Excavators, bulldozers, loaders, cranes are an integral element of any construction site. The speed and final result of construction work largely depend on their reliability. The very nature of the work performed is also connected with the level of reliability of the machines - the more responsible the work, the higher the reliability of the equipment should be.

For example, consider this type of work: an excavator loads soil into a vehicle, the soil is delivered to the construction of an embankment, then it is leveled by bulldozers and compacted by rollers. The excavator in this technological chain is the leading machine, and if it stops due to a sudden breakdown, then the entire technological chain will stop. The economic losses from such a breakdown will be very large. Therefore, the reliability of an excavator, expressed by the probability of failure-free operation, should be quite high, about 0.95.

Another option for an excavator is to dig out drainage ditches in order to lower the groundwater level in a large area wh ere a construction project will be built in a few years. An excavator digs a ditch alone for a long time, and this work is not connected with the work of other equipment, so stopping it due to a sudden breakdown, even for a week, will not have a significant impact on the economic performance of the enterprise. The probability of failure-free operation of such an excavator can be about 0.8, which corresponds to approximately six to eight years of age of the machine with an economically viable service life of 10 years.

The given examples of the level of machine reliability were determined by economic criteria - the amount of losses due to downtime. Now let's look at a crane: it is a lifting machine that operates in close proximity to buildings, power lines, equipment, and people. A malfunction of a crane associated with a fall of a boom or load can lead not only to economic losses, but also to environmental or even social damage that is disproportionately worse than economic. Therefore, the probability of failure-free operation of the crane mechanisms responsible for its safety must be at least 0.999. The reliability of the steering and brake mechanisms of a car is approximately the same.

Thus, the level of reliability is the most important indicator of machine quality.

Scientists from the SPbGASU Department of Land Transport and Technological Machines have been studying the issues of calculating the reliability of construction equipment for decades.

This computer program is based on mathematical models developed by the authors that link reliability indicators with machine service life and economic indicators. The theoretical part of the program describes the methodology for collecting and processing operational information and assessing the impact of reliability on the profitability of machine operation. The body of the program is implemented in the Excel mathematical environment.

The development of the computer program is only a small part of the authors’ many years of work on the creation of scientific and applied foundations for the reliability-oriented operation of construction machines.

Computer program No. 2023665148 is the fourth program in the field of reliability developed by the Department of LTTM. Their appearance was preceded by the writing of several monographs and dissertations. Currently, several PhD and doctoral students of the Department of LTTM are working on the problem of machine reliability in operation.

It should be noted that all computer programs developed by the staff of the department are used in the educational process. Thus, based on the programs related to reliability assessment, calculation tasks were compiled for students in the discipline “Reliability of Technical Systems”.