Horizontal motion of a rigid block resting on accelerating subsoil

The horizontal motion of the system: rigid block-accelerating subsoil is analysed, using the most simple approach. First, the method of analysis is described and illustrated for constant coefficient of friction between the block and subsoil. Then, the changing coefficient of friction is taken into account, and its influence on the motion shown. In the next step of analysis, the influence of horizontal force on permanent relative displacement of the block with respect to subsoil is illustrated for constant and changing coefficients of friction. The method presented in this paper form a basis for critical discussion of the Newmark approach, that is a kind of standard in earthquake geotechnics.