40 Pipeline Technology Journal - 1/2023 RESEARCH • DEVELOPMENT • TECHNOLOGY values of factors of safety would lead to increased de- sign requirements, expensive mitigation measures, or even rerouting. Conclusively, the proposed modification of factor of safety calculations can be considered as a significant improvement, while the parametric study has high- lighted the impact of various factors on the instabil- ity of a submarine slope from an engineering perspec- tive. Future extension could adopt more elaborate soil constitutive models and examine other failure types, e.g., planar slides of finite length and circular slides. In addition, apart from pseudo-static approaches, the in- clusion of all potential buoyancy forces should also be studied under real dynamic conditions, where all com- ponents of acceleration vary with time. References 1. E.T.R. Dean, Offshore geotechnical engineering: Principles and practice, Thomas Telford Limited, London, UK, 2010. 2. M. Randolph, S. 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ESIA Italy - Annex 7 Baseline data and maps: Appendix 11 Geotechnical report - Shallow geo- technical survey - Part A soil parameters for design. 2013. 19. N. Makrakis, P.N. Psarropoulos, D. Chatzidakis, Y. Tsompanakis, “Optimal route selection of offshore pipelines subjected to submarine lands- lides,” The Open Civil Engineering Journal, 16, e187414952209160, 2022. https://doi.org/10.2174/18743315-v16-e2208190. 20. N. R. Morgenstern, “Submarine slumping and the initiation of turbidity current,” in Marine Geotechnique, A. F. Richards, Ed. University of Illinois Press, 1967, pp. 189–220. 21. W. C. Haneberg, B. Bruce, and M. C. Drazba, “Using qualitative slope hazard maps and quantitative probabilistic slope stability mo- dels to constrain least-cost pipeline route optimization,” in Offshore Technology Conference, 2013, pp. 1–11, doi: 10.4043/23980-ms. 22. C. Melo and S. Sharma, “Seismic coefficients for pseudostatic slope analy- sis,” in 13th World Conference on Earthquake Engineering Vancouver, B.C., Canada August 1-6, 2004 Paper No. 369, 2004, p. 15. Authors Prodromos Psarropoulos National Technical University of Athens Structural & Geotechnical Engineer prod@central.ntua.gr Yiannis Tsompanakis Technical University of Crete Professor of Computational Dynamics & Earthquake Engineering jt@science.tuc.gr Nikolaos Makrakis Technical University of Crete Surveying & Earthquake Engineer makr.nickos@gmail.com