... (Fig. 2). The springs were pretensioned such that they never went slack during the test runs. Thus, the spri ng-mass system had an equi val ent spri ng constant equal to twice the spring constant of each spring set. The tanker was fitted with a two-directional gyroscope to measure the pitch and roll...

... significant wave height natural frequency interaction mechanism spring constant stiffness storm OTe 5222 Measured Soil-Structure Interaction Properties of a Gravity Platform by N. Spidsoe and O. Skj~stad, SINTEF Copyright 1986 Offshore Technology Conference This paper was presented at tfle-18Th Annual...

... with little loss of accuracy. This facil itates their use in frequency domain analysis. The equations were linearized about the mean position of the tensioning system (ZH =0) and the mean fleet angle (90 j. The linearized equations, A.3 and A.4, give stiffness terms (spring constants) which relate the lateral...

... of the riser contents ("mud") is simply lumped onto the bottom of the riser. This approach ignores the compressibility of the trapped fluid column. The equivalent axial spring constant of a fluid column that results from compressibilit~ has been derived. The derived spring constant is then employed in both...

... to KA78-02 and KA78-04, there is a peak around 1.0 ~ 1.2 Hz instead of 0.9 Hz. Figures 9 and 10 show the relationship between peak frequency of transfer function and/or spring con- stant of the platform versus to the displacement of the platform deck. Spring constant is calculated assuming that the peak...

.... This paper discusses in detail an important concept with regard to dynamic applications of synthetic lines and explains its significance to the designer: the dynamic stiffness, or apparent spring constant, is 3-4 times greater than the quasi-static spring constant which is often misapplied to dynamic...

... records include frequency components up to about 25 Hz. Pile-Head Spring Constants and Damping Coefficients Pile-head spring constants and damping coeffi- cients are important to the characterization of the SPS response as they control the responses of the pile due to pile-head loads. Under the steady...

...-frequency longitudinal surge phenomena in still water and in head waves of a VLCC and a LNG carrier moored in relatively deep water. extinction test regular wave natural frequency surge motion upstream oil & gas rad moored vessel wave drift force spring constant equation hydrodynamic...

... with an equivalent spring constant in its range of application. The nonlinear drag term is also linearized. Under these assumptions, the equations of motion can be solved in a semi-closed form solution. To verify the validity of the assumptions made, a series of wave tank tests were performed with a tower-tank...

... relationship: l~~n = 21T '" M , where K is the stiffness or the spring constant, and Mis the effective mass. __ The probe is, in effect, a cantilever and, therefore, the stiffness is given by the following relationship. K = 3EI 13 where E is the modulus of elasticity, I is the moment of inertia, and 1...

... captive vessel engineer mdwt tanker moored ship lateral motion coefficient impulse-response function calculation mowt tanker moored vessel nference paper 6200 mooring system water depth spring constant ship equation reservoir characterization upstream oil & gas tanker...

... characteristic weather upstream oil & gas moored vessel water depth requirement equation axis displacement pretension dp controller augmentation subsea system mooring system otc 2064 positioning spring constant controller engineer representation dp system integral gain...

... cable system equation spring constant static spring constant upstream oil & gas luency engineer coefficient cable slack oscillationtest OFFSHORE TECHNOLOGY CONFERENCE 6200 North Central Expresswgy Dallas; Texas 75206 .. THIS IS A PREPRINT SUBJECT TO CORRECTION =~ OTC 1156 Analytical...

... variation platform vector drag coefficient coefficient displacement tension leg stable platform upstream oil & gas random wave evaluation matrix spring constant equation prediction amplitude model 1 OFFSHORE TECHNOLOGY CONFERENCE 6200_North Central Expressway Dallas, Texas 75206...