A numerical time-simulation algorithm for analysing highly nonlinear solita
ry waves interacting with plane gentle and steep slopes is described by emp
loying a mixed Eulerian-Lagrangian method. The full nonlinear free surface
conditions are considered here in a Lagrangian frame of reference without a
ny analytical approximations, and thus the method is valid for very steep w
aves including overturning. It is found that the runup height is crucially
dependent on the wave steepness and the slope of the plane. Pressures and f
orces exerted on impermeable walls of different inclinations (slopes) by pr
ogressive shallow water solitary waves are studied. Strong nonlinear featur
es in the form of pronounced double peaks are visible in the time history o
f pressure and force signals with increasing heights of the oncoming solita
ry waves. The effect of nonlinearity is less pronounced as the inclination
of the wall decreases with respect to the bottom surface. (C) 1999 Elsevier
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