• Title/Summary/Keyword: Arctic marine structural steel

Search Result 2, Processing Time 0.019 seconds

Impact Bending Test Simulations of FH32 High-strength Steel for Arctic Marine Structures

  • Choung, Joonmo;Han, Donghwa;Noh, Myung-Hyun;Lee, Jae-Yik;Shim, Sanghoon
    • Journal of Advanced Research in Ocean Engineering
    • /
    • v.2 no.1
    • /
    • pp.28-39
    • /
    • 2016
  • This paper provides theoretical and experimental results to verify the crashworthiness of FH32 high-strength steel for arctic marine structures against ice impact. Assuming that side-shell structures of the Korean arctic research vessel, ARAON, with ice-notation PL10, collide with sheet ice, one-third-scale test specimens with a single transverse frame are manufactured. Impact-bending tests were conducted using a rigid steel striker that mimics sheet ice. Drop height was calculated by considering the speed at which sheet ice is rammed. Prior to impact-bending tests, tensile coupon tests were conducted at various temperatures. The impact-bending tests were carried out using test specimens fully fixed to the inside bottom frame of a cold chamber. The drop-weight velocity and test specimen deformation speed were measured using a high-speed camera and digital image correlation analysis (DICA). Numerical simulations were carried out under the same conditions as the impact-bending tests. The simulation results were in agreement with the test results, and strain rate was a key factor for the accuracy of numerical simulations.

Numerical Analysis of Iceberg Impact Interaction with Ship Stiffened Plates Considering Low-temperature Characteristics of Steel (강재의 저온 특성을 고려한 선체 보강판과 빙하의 충격 상호 작용에 대한 수치 해석)

  • Nam, Woongshik
    • Journal of Ocean Engineering and Technology
    • /
    • v.33 no.5
    • /
    • pp.411-420
    • /
    • 2019
  • It is essential to design crashworthy marine structures for operations in Arctic regions, especially ice-covered waters, where the structures must have sufficient capacity to resist iceberg impact. In this study, a numerical analysis of a colliding accident between an iceberg and stiffened plates was carried out employing the commercial finite element code ABAQUS/Explicit. The ice material model developed by Liu et al. (2011) was implemented in the simulations, and its availability was verified by performing some numerical simulations. The influence of the ambient temperature on the structural resistance was evaluated while the local stress, plastic strain, and strain energy density in the structure members were addressed. The present study revealed the risk of fracture in terms of steel embrittlement induced by ambient temperature. As a result, the need to consider the possibility of brittle failure in a plate-stiffener junction during operations in Arctic regions is acknowledged. Further experimental work to understand the structural behavior in a plate-stiffener junction and HAZ is required.