Set-up considerations in wave equation analysis of pile driving

Set-up effects should be accounted for to obtain reliable estimates of driving resistance using WEAP analysis because both the bearing capacity of driven piles, and other dynamic parameters, show a tendency to change with time. Unfortunately, there are no reliable methods that take set-up effects into consideration in wave equation analysis, even though much research has been conducted in this area. Therefore it is desirable to propose new soil input parameters to account for time dependent characteristics. For this purpose, statistical analyses of dynamic measurements for both 'end of driving' and 'restrike' conditions have been undertaken. The paper recommends new parameters that take account of set-up effects for wave equation analysis, and quantifies the reliability of the recommended values by means of statistical analyses on independent pile tests. It is shown that the recommended quake and damping parameters are more reliable than existing suggestions for wave equation analysis of driven piles.