PSI - Issue 37

Zijah Burzić et al. / Procedia Structural Integrity 37 (2022) 269 – 273 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

273

5

=

[ 1 √ ] ∫ − 2 0

(3)

In this way one gets ΔN= 915,557. If frequency is taken as 1 Hz, one gets only 254 hours for the life expectancy. If amplitude loading is taken as Δσ max =10 MPa, producing ΔK=15.7 MPa∙√m, one gets ΔN=13,964,781, i.e. 3,879 hours, which is still far from being acceptable. In any case, supporting steel construction was repaired and reconstructed in the meantime, preventing failure which looked like immanent, even if one takes into account all conservative assumptions used in this calculation. 4. Conclusions Based on the results presented in this paper, one can conclude that the crack length detected by NDT in welded joint of the steel structure supporting “Gazela” bridge are far above acceptable values, so there was a danger of brittle and/or fatigue failure, which was prevented by timely performed repair and reconstruction. Acknowledgements This research was supported by the Ministry of Sciences and Technology of Republic of Serbia through the contracts 451-03-9/2021-14/200105 and 451-03-9/2021 -14/200213. References [1] Aranđelović, M., Sedmak, S., Jovičić, R., Perković, S., Burzić, Z., Đorđević, B., Radaković, Z., Numerical simulation of welded joint with multiple various defects, Structural Integrity and Life, Vol.21, No. 1, 2021, 103 – 107 [2] Sedmak, S., Jovičić, R., Sedmak, A., Aranđelović, M., Đorđević , B., Influence of Multiple Defects in Welded Joints Subjected to Fatigue Loading According to SIST EN ISO 5817:2014, Structural Integrity and Life, Vol. 18, No. 1, 2018, 77-81 [3] Mijatović, T. et al, Structural Integrity Assesment from the Aspect of Fracture Mechanics, Structural Integrity and Life, Vol.19, No.2, 2019, pp.121 – 124 [4] Jeremić, L., Sedmak, A., Milovanović, N. , Milošević, N., Sedmak, S., Assessment of integrity of pressure vessels for compressed air, Structural Integrity and Life, Vol. 21, No. 1, 2021, 3-6 [5] Olanrewaju Busari, Y., Prasada Manurung, Y., Welded high strength low alloy steel influence on fatigue crack propagation of using LEFM: A practical and thematic review, Structural integrity and life, Vol. 20, No 3 (2020), p. 147-151. [6] Arsić, M., Karić , R., Sedmak, A., Burzić, M., Vistać, B., Methodological approach to integrity assessment and service life of rotating equipment at hydropower plant-turbine shaft, Structural integrity and life, Vol. 13, No 2 (2013), p. 177-124. [7] Sedmak, A., Bosnjak, S., Arsic, M., Savic, Z., Integrity and life estimation of turbine runner cover in a hydro power plant, Frattura ed Integrita Strutturale 10(36):63-68, April 2016. [8] Jovanović, M . Čamagić, I., Sedmak, S., Živković, P., Sedmak, A., Crack Initiation and Propagation Resistance of HSLA Steel Welded Joint Constituents, Structural integrity and life, Vol. 20, No 1 (2020), pp. 11-14. [9 ] Arsić, M., Karić, R., Sedmak, A., Burzić, M., Vistać, B., Methodological Approach to Integrity Assessment and Service Life of Rotating Equipment at Hydropower Plant – Turbine Shaft, Structural Integrity and Life, Vol. 14, No 2 (2014), pp. 141-146. [10] Đurđević, A., et al, Numerical simulation of fatigue crack propagation in friction stir welded joint made of Al 2024-T351 alloy, Engineering Failure Analysis, Volume 58, Pages 477 – 484, 2015 [11] Krаedegh, A., Li, W., Sedmak, A., Grbovic, A., Trišović, N., Mitrović R., Kirin, S., Simulation of fatigue crack growth in A2024-T351 Tt welded joint, Structural Integrity and Life, Vol. 17, No. 1, 2017, 3-6 [12] Sedmak A., Computational fracture mechanics: An overview from early efforts to recent achievements. Fatigue Fract Eng Mater Struct. Vol. 41, p. 2438 – 2474, 2018 [13] ASTM E1820 - 20b Standard Test Method for Measurement of Fracture Toughness, 2020 [14] ASTM E647 - 15e1 Standard Test Method for Measurement of Fatigue Crack Growth Rates, 2015 [15] Sedmak, A.. et al, Fatigue crack growth parameters for welded joints – bridge “Gazela”, plenary lecture at the International Conference, CIBv, Brasov, 2017