Lateral Resistance |
 
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Lateral Resistance |
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The Lateral Seabed Stiffness entry specifies a lateral resistance to horizontal motion on the elastic seabed. The facility is activated by inputting a lateral spring stiffness per unit length, and the resistance this provides is integrated into a seabed stiffness matrix for any element on the mudline in a similar manner to the vertical seabed resistance. Naturally one effect is defined in terms of seabed axes and the other in terms of a local axis system, which may vary from element to element. However this is readily handled by Flexcom. The resistance to horizontal motion provided by the lateral spring replaces rather than augments transverse friction (seabed friction modelling is described later in ‘Seabed Friction’). The two effects cannot be combined. If you input a non-zero value for both the lateral seabed stiffness and the transverse friction coefficient, Flexcom outputs a warning and sets the friction coefficient to zero. Note that whichever of these effects is present in an analysis provides lateral resistance to elements on the seabed only, and not to elements in the suction zone.
•*SEABED PROPERTIES is used to specify properties such as seabed type (i.e. rigid or elastic) and friction parameters. Specifically, the LATERAL= input is used to specify a lateral resistance to horizontal motion.