Estimation of long-term settlement and determination of additional sampling positions using GIS

Abstract

We estimate the ground information for the interesting region by using the results obtained from in-situ and laboratory tests with GIS (Geographic Information Systems). Incheon International Airport that was reclaimed is the objective area in this paper. The settlements of the ground surface have been measured at the beginning of the construction. Since the primary consolidation in this site has been completed, the settlement due to the secondary consolidation was expected and predicted by the SSCI (Secant Secondary Compression Index). To estimate the long-term settlement in the future, geostatistics, such as the 'Kriging interpolation method' and the 'IDWI (Inverse Distance Weighted Interpolation) method' in GIS was used. The results by the IDWI method are compared with those by Kriging interpolation method. Using the concept of 'thoroughness', additional sampling positions are proposed. As a result, it is known that 1) the GIS can be useful tool to estimate soil parameters at any point without the measurement in site or test in the lab; 2) the long-term settlement estimated by the Kriging interpolation method show better agreement with the measured ones than IDWI method; and 3) the GIS can be useful to estimate the long-term settlement in the future and additional sampling positions.