Vertical bending moments and axial forces in a floating marine hose-string

The primary mechanisms by which vertical bending moments and axial forces are induced in a floating hose-string attached to a CALM buoy are quantitatively assessed by means of model tests and analytical study. It is found that the dynamic axial forces on the hose-string are determined by the push-pull action exerted on the string by the surge response of the buoy in waves. If the surge characteristics of the buoy are known, dynamic axial forces along the hose-string may be estimated using the empirical model presented. The dynamic vertical bending moment on the hose at the buoy mostly depends on the heave response of the buoy in waves. Good estimates of the vertical bending at the buoy may be obtained using the analytical model presented. © 1990.