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Abstract

This paper presents an analysis of the stator teeth geometry impact on the parameters of the 8-pole radial magnetic bearing. In this paper, such parameters as current gain and position stiffness have been analysed. Additionally, we have proposed criteria for evaluating the characteristics of these parameters by calculating the variability of current gain and position stiffness. The research has been performed by solving the magnetic bearing actuator boundary problem using the finite element method. Magnetic force has been calculated using the Maxwell stress tensor method. Other parameters, such as current gain and position stiffness have been calculated as partial derivate of the force with respect to control current and position of the rotor.

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Authors and Affiliations

Bronisław Tomczuk
Dawid Wajnert
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Abstract

The list of potential hazards related to concrete elements and structures prestressed with the use of unbonded tendons, including the flat slabs, is long and fairly well recognized. In addition to the standard accidental events this list includes: mishandling during construction, small fire, local corrosion, loss of bond at the anchorage, second order effects, brittle fracture of elements, etc. Despite of these hazards related to unbonded post-tensioning, this type of structures are extensively promoted and used in practice thanks to the possibility of the large span floors and innovative character of this technology. The paper presents a proposal for the application of risk analysis to assess the robustness of structures with flat slabs prestressed with unbonded tendons. The adoption of variables that determine risk and robustness as fuzzy numbers assigned to linguistic variables are proposed. Numerical example is presented to demonstrate risk and robustness assessment of building structure with unbonded posttensioned slabs supported directly on columns.
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Bibliography

[1] F. Knoll, T. Vogel, Design for Robustness. Structural Engineering Documents No11. Zurich: IABSE, 2009, ISBN 978-3-85748-120-8.
[2] Santa Fe Institute, RS-2001-009, Working definitions of robustness, 2001. [Online].Available: http://discuss.santafe.edu/robustness/sories.
[3] E.A.P. Liberati, C.G. Nogueira, E.D. Leonel, “Nonlinear formulation based on FEM, Mazars damage criterion and Fick’s law applied to failure assessment of reinforced concrete structures subjected to chloride ingress and reinforcements corrosion”, Engineering Failure Analysis, 2014, vol. 46, pp. 247–268, DOI: 10.1016/j.engfailanal.2014.09.006.
[4] N.C. Lind, “Measures of vulnerability and damage tolerance”, Reliability Engineering & System Safety, 1995, vol. 48, no. 1, pp. 1–6.
[5] D.M. Frangopol, J.P. Curly, “Effects of damage and redundancy on structural realibility”, Journal of Structural Engineering, 1987, vol. 113, no. 7, pp. 1533–1549.
[6] S. Woo, D.L. O’Neal, “Reliability design and case study of mechanical system like a hinge kit system in refrigerator subjected to repetitive stresses”, Engineering Failure Analysis, 2019, vol. 99, pp. 319–329, DOI: 10.1016/j.engfailanal.2019.02.015.
[7] I.W. Baker, M. Schubert, M.H. Faber, “On assessment of robustness”, Journal of Structural Safety, 2008, vol. 30, pp. 253–267.
[8] ISO Standard 19902, Petroleum and natural gas industries – Fixed steel offshore structures, 2008.
[9] T. Vrouwenvelder, et al., Eds. Risk assessment and risk communication in civil engineering. CIB Report, 259. Rotterdam: CIB General Secretariat, 2001.
[10] EN 1991-1-7, Eurocode 1 – Actions on structures – Part 1–7: General actions – Accidental actions.
[11] A. del Caño, M. Pilar de la Cruz, D. Gómez, M. Pérez, “Fuzzy method for analysing uncertainty in the sustainable design of concrete structures”, Journal of Civil Engineering and Management, 2016, vol. 22, no. 7, pp. 924–935, DOI: 10.3846/13923730.2014.928361.
[12] S. Boral, I. Howard, S.K. Chaturvedi, K. Mc Kee, V.N.A. Naikan, “An integrated approach for fuzzy failure modes and effects analysis using fuzzy AHP and fuzzy MAIRCA”, Engineering Failure Analysis, 2020, vol. 108, ID Article: 104195, DOI: 10.1016/j.engfailanal.2019.104195.
[13] Sz.Wolinski, “Defining of the structural robustness”, Bulletin of the Polish Academy of Sciences, Technical Sciences, 2013, vol. 61, no. 1, pp. 137–144, DOI: 10.2478/bpasts-2013-0012.
[14] H. Bandamer, S. Gottwald, Fuzzy Sets, Fuzzy Logic, Fuzzy Methods with Applications. Chichester: J.Wiley & Sons, 1995.
[15] EN 1990:2004 Eurocode- Basis of structural design.
[16] G. Harding, J. Carpenter, “Disproportional collapse of Class 3 buildings: the use of risk assessment”, The Structural Engineering, 2009, vol. 87, no. 15-16, pp. 29–34.
[17] Bai Yu, Hou Jian, Huang Yuan, “Progressive collapse analysis and structural robustness of steel-framed modular buildings”, Engineering Failure Analysis, 2019, vol. 104, pp. 643–656, DOI: 10.1016/j.engfailanal. 2019.06.044.
[18] G. Milani, M. Valente, “Comparative pushover and limit analyses on seven masonry churches damaged by the 2012 Emilia-Romagna (Italy) seismic events: Possibilities of non-linear finite elements compared with pre-assigned failure mechanisms”, Engineering Failure Analysis, 2015, vol. 47, Part A, pp. 129–161, DOI: 10.1016/j.engfailanal.2014.09.016.
[19] Sz. Wolinski, T. Pytlowany, “Analysis of the state of prestressed structure using data collection simulation technique”, MATEC Web of Conferences, 2019, vol. 262, DOI: 10.1051/matecconf/201926208006.
[20] Sz. Wolinski, T. Pytlowany, “Risk and robustness assessment for floor slabs prestressed with unbonded tendons”, in Konstrukcje betonowe i stalowe, (in Polish). Bydgoszcz: University of Science & Technology, 2015, pp. 137–144.
[21] Sz. Wolinski, “Robustness and vulnerability of slab structures”, Procedia Engineering, 2017, vol. 193, pp. 88–95, DOI: 10.1016/j.proeng.2017.06.190.
[22] JCSS: Probabilistic Model Code, The Joint Committee on Structural Safety. [Online]. Available: https://www.jcss-lc.org/jcss-probabilistic-model-code/.
[23] E.A.P. Liberati, C.G. Nogueira, E.D. Leonel, “Nonlinear formulation based on FEM, Mazars damage criterion and Fick’s law applied to failure assessment of reinforced concrete structures subjected to chloride ingress and reinforcements corrosion”, Engineering Failure Analysis, 2014, vol. 46, pp. 247–268, DOI: 10.1016/j.engfailanal.2014.09.006.
[24] B. Rodowitz, M. Schubert, M. Faber Havbro, “Robustness of Externally and Internaly Post Tensioned Bridges”, Beton und Stahlbetonbau, 2008, vol. 103, pp. 16–22, DOI: 10.1002/best.200810111.
[25] B. Rodowitz, Robustheit von Balkenbrucker mit externer und interner Vorspannung. Institut fur Massivbau und Baustofftechnologie, Abtailung Massivebau. Karlsruhe: Universitat Karlsruhe, 2007 (in German).
[26] A. Setareh, H. Saffari, J. Mashhadi, “Assessment of dynamic increase factor for progressive collapse analysis of RC structures”, Engineering Failure Analysis, 2018, vol. 84, pp. 300–310, DOI: 10.1016/j.engfailanal.2017.11.011.
[27] I. Skrzypczak, L. Buda–Ozóg, T. Pytlowany, “Fuzzy method of conformity control for compressive strength of concrete on the basis of computational numerical analysis”, Meccanica, 2016, vol. 51, no. 2, pp. 383–389, DOI: 10.1007/s11012-015-0291-0.
[28] Sz. Wolinski, T. Pytlowany, “Parametric Analysis of the Sensitivity of a Prestressed Concrete Beam Using the DOE Simulation Technique”, Archives of Civil Engineering, 2019, vol. 65, no. 4, pp. 97–112, DOI: 10.2478/ace-2019-0049.
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Authors and Affiliations

Szczepan Woliński
1
ORCID: ORCID
Tomasz Pytlowany
2
ORCID: ORCID

  1. Rzeszów University of Technology, The Faculty of Civil and Environmental Engineering and Architecture, Powstanców Warszawy 12, 35-084 Rzeszów, Poland
  2. Carpathian State College in Krosno, Politechnik Institutution, Dmochowskiego 12, 38-400 Krosno, Poland

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