Abstract: The Asaoka Method is one of most used graphical analysis methods in the settlement prediction of highspeed rail embankments. However, the limitation of this method is that the settlement data interval must be constant. In the construction practice, the monitoring data could not always meet this requirement so that the data conversion is necessary. Currently, little research literatures are available regarding the data conversion into the constant time intervals. This paper introduces three methods of constant time interval data conversion; namely, linear interpolation; spline interpolation and piecewise cubic Hermite interpolation. All methods are used in the ultimate settlement prediction analysis of a highspeed rail embankment. The accuracy of these predictions is also compared in the paper.

Key words: Asaoka Method, Ultimate Settlement Prediction, Constant Time Interval, Linear Interpolation Method, Spline Interpolation Method, Piecewise Cubic Hermite Interpolation Method