Projekteja vuodessa
Abstrakti
Deflection of a free, thin, square, elastic, point-loaded ice sheet is studied. A three-dimensional, combined finite element-discrete element method (FEM-DEM) is applied. Examined is a set of square, self-similar (plan view) ice sheet samples with the side lengths of L=20, 40, 80, and 160 m; thicknesses of h=0.5, 1.0, and 1.5 m; and the average discrete element sizes of l=2h and 3h. The samples are generated and meshed via a centroidal Voronoi tessellation procedure. Each mesh is unstructured and consists of convex polyhedra as the discrete elements and a Delaunay-triangulated, in-plane beam lattice of co-rotational, viscously damped Timoshenko beam finite elements. Two load cases are considered: a sheet sample subjected to i) a vertical, centrally applied point load; and ii) a vertical point load on an edge. In both load cases, a good agreement is found between the deflections computed with the FEM-DEM approach and with FEM. Maximum, non-dimensionalized deflections w¯max (w¯max=q/Fz, where q=q(wmax) is an approximate, resultant reaction force due to the buoyancy, wmax the computed maximum deflection, and Fz the applied point load) scale, in each load case, either by a power-law, w¯max∝hm1(L), or exponentially, w¯max∝10m2(h)L, depending on whether computed over h (for each L) or vice versa. The exponents m1 and m2 are not constants, but functions of L and h, respectively, and approximately equal in either load case. In-plane size estimates are sought for an FEM-DEM sheet sample to represent either a) an infinite, elastic, point-loaded ice sheet; or b) a semi-infinite, elastic, point-loaded (with the load on the free edge) ice sheet with a free edge. A free, square, point-loaded FEM-DEM sheet sample well approximates both a) and b), if L/2>≈5lch, where lch denotes a characteristic length.
Alkuperäiskieli | Englanti |
---|---|
Artikkeli | 102644 |
Sivumäärä | 31 |
Julkaisu | Marine Structures |
Vuosikerta | 68 |
Varhainen verkossa julkaisun päivämäärä | 19 elok. 2019 |
DOI - pysyväislinkit | |
Tila | Julkaistu - marrask. 2019 |
OKM-julkaisutyyppi | A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä |
Sormenjälki
Sukella tutkimusaiheisiin 'A free, square, point-loaded ice sheet : A finite element-discrete element approach'. Ne muodostavat yhdessä ainutlaatuisen sormenjäljen.Projektit
- 2 Päättynyt
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ICESCALE: Scaling of Ice Strength: Measurements and Modeling
Polojärvi, A. (Vastuullinen tutkija) & Forsström, A. (Projektin jäsen)
03/11/2015 → 31/12/2018
Projekti: Business Finland: Other research funding
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ARAJÄÄ: Arktisten rakenteiden jääkuormat: mallikokeista teollisuuden mittakaavaan
El Gharamti, I. (Projektin jäsen), Polojärvi, A. (Vastuullinen tutkija), Forsström, A. (Projektin jäsen), Schneider, S. (Projektin jäsen), Rytömaa, S. (Projektin jäsen), Kulovesi, J. (Projektin jäsen), Taimuri, G. (Projektin jäsen) & Lemström, I. (Projektin jäsen)
01/09/2015 → 31/03/2019
Projekti: Business Finland: Other research funding