Consolidation Coefficient in Horizontal Direction (Ch) Determined from Field Settlement Data By Using Terzaghi, Asaoka, and Finite Element Methods

Abstract

In order to predict the consolidation period in the field, consolidation coefficient in vertical direction (C v ) parameter is needed. When vertical drains installed in the compressible layer in order to shortened the consolidation period, it needs consolidation coefficient in horizontal direction (C h ). This C h parameter has to be determined from the field settlement that usually obtained from the trial embankment. However, it is very expensive to carry out the trial embankment; therefore, it is usually assumed to be 2 till 5xC v . In this paper, the assumption of the C h value will be proven b y using field settlement data taken from the trial embankment at the reclamation area for container yard at Kuala Tanjung, M edan, By choosing the C h value, the compression vs time curves were predicted by adopting the Terzaghi, Asaoka, and Finite Element methods. Afterwards, these predicted settlement curves were plotted with the field settlement curves; from this plotting, it could be figured out the predicted curves which has C h value the same with the field C h value. The results show that from three methods adopted in this study, only the Terzaghi and the Asaoka methods give satisfactory results in settlement prediction. Consequently, only the Terzaghi and Asaoka methods are adopted to determine the C h value. The C h value obtained is about the same, that is 3C v until 5C v . When that C h value used back to predict the settlement, the Asaoka method gives better result than the Terzaghi method.