Jt: Toe damping coefficient EOID: End of initial driving

ABSTRACT. Thtipaper deals with application of the wave equation to pile driving analysis. It is shown that changes of the pile-soil system related to soil remolding around pile should be taken into account for reliable prediction ofpile capacity after the end of initial driving. Soil damping is the basic parameter for adjustment of wave equation solution with time-dependent soil properties. Experimental data was acquired for three piles, one in clay and two in sand. Adjusted wave equation solutions yield an increase of soil damping with elapsed time after the end of driving with laker intensity in clay. A linear relationship between the skin damping coef&ient and time elapsed after driving was approximately found for piles in clay and sand. NOMENCLATURE J, : Skin damping coefficient J Skin damping coefficient at EOIDse J sr: Skin damping coefficient at RST