A Reliability Analysis of the Foundations of Machines and Mechanisms under Periodic Loads by the Criterion of Oscillation Amplitude
Authors: Utkin V.S. | Published: 11.07.2017 |
Published in issue: #7(688)/2017 | |
Category: Calculation and Design of Machinery | |
Keywords: reliability of a machine foundation, oscillation amplitude, random value, fuzzy variable, possibility of failure, failure-free operation |
The article describes methods of reliability analysis of the foundations of machines and mechanisms under periodic loads with regard to the criterion of oscillation amplitude. These methods take into account the varying volume and quality of initial statistical information about the controlled parameters in mathematical models of limit states at the stages of installation and operation. The controlled parameters in the mathematical model of the limit state are described by probabilistic, possibilistic and combined methods depending on the completeness (or incompleteness) of statistical information. With full statistical information about the parameters (random values) in mathematical models of limit states, probabilistic statistical methods are used for calculating reliability, with the description of parameters by probability distribution functions. As a result, a single-value probability estimate of the level of reliability of the foundation is obtained. With limited (incomplete) statistical information about the parameters (fuzzy variables), possibilistic methods of reliability calculations are used, according to which reliability is characterized by an interval of probabilities where only the boundaries of the interval are known, i.e. the result of the calculations is less informative. When dealing with parameters with both full and limited statistical information, combined methods are used for calculating reliability. The choice of the methods depends on the type of the information available. Due to the fact that some parameters can be described by probabilistic methods, while others by possibilistic ones, it is possible to reduce the range of the calculated reliability interval, for example that of the foundation, and to increase the information value of the calculation results, which will allow the designer to make decisions more objectively.
References
[1] GOST 27.002–2015. Nadezhnost’ v tekhnike. Terminy i opredeleniia [State Standard 27.002–2015. Dependability in technics. Terms and definitions]. Moscow, Standartinform publ., 2016. 24 p.
[2] Bolotin V.V., Nefedov S.V., Chirkov V.P. Nadezhnost’ v tekhnike. Metodologiia raschetnogo prognozirovaniia pokazatelei nadezhnosti. Metody teorii veroiatnostei [Reliability in technique. The methodology of forecasting of indicators of reliability. Methods of probability theory]. Moscow, MNTK Nadezhnost’ mashin publ., 1993. 172 p.
[3] Trukhanov V.M. Metody obespecheniia nadezhnosti izdelii mashinostroeniia [Methods of ensuring the reliability of engineering products]. Moscow, Mashinostroenie publ., 1995. 304 p.
[4] Mondrus V.L., Smirnov V.A. Vibrozashchita vysokotochnogo oborudovaniia ot nizkochastotnykh kolebanii [Evaluation of Wall Structures Resistance on the Basis of Modifired Analog Rods Models]. ACADEMIA. Arkhitektura i stroitel’stvo [Academia. Architecture and construction]. 2011, no. 1, pp. 109–111.
[5] Smirnov V.A. Vibroizoliator kvazinulevoi zhestkosti [The quasi-zero stiffness vibration isolator]. Patent RF no. 2516967, 2014.
[6] Utkin V.S. Raschet nadezhnosti mekhanicheskikh sistem pri ogranichennoi statisticheskoi informatsii [Calculation of reliability of mechanical systems with bounded statistical information]. Vologda, VoSTU publ., 2008. 188 p.
[7] Utkin V.S. Nadezhnost’ mashin i oborudovaniia [Reliability of machinery and equipment]. Vologda, VoSTU publ., 2007. 159 p.
[8] Zemlianskii A.A. Obsledovanie i ispytanie zdanii i sooruzhenii [Inspection and testing of buildings and structures]. Moscow, ASV publ., 2001. 240 p.
[9] Vibroizmeritel’nye pribory, izmeriteli vibratsii, vibrometry [Vibration measuring devices, vibration meters, vibration meters]. Available at: http://www.stroypribor.ru/produkt/ (accessed 15 March 2017).
[10] Diubua D., Prad A. Teoriia vozmozhnostei. Prilozheniia k predstavleniiu znanii v informatike [The theory of possibilities. Application to knowledge representation in computer science]. Moscow, Radio i sviaz’ publ., 1990. 288 p.
[11] Utkin V.S. Znachenie urovnia riska v teorii vozmozhnostei [The value of the level of risk in the theory of opportunities]. Stroitel’nye materialy [Construction Materials], 2004, no. 8, p. 35.
[12] Ross T.J. Fuzzy logic with Engineering Applications. England, John Wiley & Sons, 2004. 650 p.
[13] Utkin V.S. Calculating of the shaft reliability (Strength) on the Basis of Limited Information. Russian Engineering Research, 2011, vol. 31, no. 2, pp. 119–122.
[14] Utkin V.S. Calculating the reliability of machine parts on the basis of the Chebyshev inequality. Russian Engineering Research, 2012, vol. 32, no. 1, pp. 5–8.