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SACS SACS is an integrated finite element structural analysis package of applications that uniquely provides for the design of offshore structures, including oil and gas platforms, wind farms, and topsides of FPSOs and floating platforms. SACS software…

EARLIER Q: There are supposed to be three unity ratios reported in the Hydrostatic Collapse Check. Why in some cases is one of them missing? REV 5.07 A: The code has three sections: hoop stress, tension, and compression. For some cases, there can…

EARLIER Q: Do the API ratios obtained during a hydrostatic collapse check on a beam include the Safety Factors defined by the API for Axial and Hoop stresses (1.67 and 2.0)? REV 7.00 A: Of course they include the safety factors - without them it would…

Q: I have a hull hydrostatic model and a hull structural model, whereby I compare the deflections of the two models. The structural model is composed of two longitudinal beams and some transverse link beams, both made up of prismatic sections. The deflection…

Q: I have a rectangular barge modeled as a line of beams with a uniform load distribution. Why are the structural bending moments and shears not what I get from statics? REV 7.00 A: The difference is the way the loads are applied. The weight is divided…

Q: Why is the hydrostatic bending moment different from the structural one computed from RAOs? REV 7.05 A: The two results deserve to be different: For the hydrostatic bending moment, MOSES assumes that the wave changes the shape of the water surface…

Q: I have compartments with pump contents type of “-correct”. The permeability of the compartments is set to 1.00. Why do I have problems finding hydrostatic equilibrium after issuing the "CMP_BAL"? I do not get this message if I choose one of the other…

Q: I was looking at the hydrostatic coefficients generated from MOSES and noticed that the moment to cause trim by 0.01 degree uses BMl instead of GML in the computation. This is the same whether or not I give a value for KG. Does this approximation continue…

Q: Is the stiffness matrix (hydrostatic and connector) used in MOSES a 3 X 3 matrix with coupling terms, using the assumption of small motions? REV 5.03 A: No, this stiffness matrix is a N X N matrix where N is 6 times the number of bodies. In the frequency…

Q: Is it possible to get the hydrostatic stiffness matrix from MOSES? REV 7.01 A: Not directly. If you do the following &status force &instat -move bod 0 0 1 0 0 0 &status force The difference in the buoyancy force between the two the force…

Q: I have a piece that I want to be included for hydrodynamic calculations but I do not want it included for hydrostatic calculations. What options do I used in the definition? REV 7.04 A: You need to give the part just a little bit of displacement…