caa a22 4500 47573727X CHVBK 20180406123450.0 cr unu---uuuuu 170329e20001201xx s 000 0 eng 10.1007/PL00010631 doi (NATIONALLICENCE)springer-10.1007/PL00010631 Kashiwagi Masashi Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan, JP aut A time-domain mode-expansion method for calculating transient elastic responses of a pontoon-type VLFS [Elektronische Daten] [Masashi Kashiwagi] A time-domain calculation method is described for elastic responses to arbitrary time-dependent external loads, on the basis of a general differential equation of second order including the convolution integral related to memory effects in the hydrodynamic forces. The time-dependent elastic deflection of a structure is represented by a superposition of mathematical modal functions, and a Galerkin scheme is employed to obtain a linear system of simultaneous differential equations for the amplitude of modal functions assumed. Special care is paid to numerical accuracy in computing the memory-effect function and the added mass at infinite frequency. The validity of the numerical results was confirmed through a comparison with time histories of the vertical deflection measured in an impulsive weight-drop test conducted at the Ship Research Institute and a comparison with existing numerical results for the same problem. To check the necessity of memory-effect terms, computations using a constant value for the hydrodynamic damping coefficient were also performed, and practical measures for reducing the computation time are discussed. The Society of Naval Architects of Japan, 2000 Key words Very large floating structure nationallicence Hydroelastic response nationallicence Time domain nationallicence Memory effect nationallicence Convolution integral nationallicence https://doi.org/10.1007/PL00010631 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/PL00010631 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Kashiwagi Masashi Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-koen, Kasuga, Fukuoka 816-8580, Japan, JP aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer