Correlations Between Liquefaction Potential Indices Assessed by CPTu and SPT Methods

CPTu is a more reliable and high resolution investigation method than SPT in achieving better site characterization. However, due to the rich experience of liquefaction and non-liquefaction SPT-N cases in the past, the SPT methods are still more popular in use than CPTu ones in engineering practice. It is well known that there exists considerable discrepancy of the liquefaction assessment results between the CPTu and SPT methods. The former usually yields more conservative result. To promote the practical application of CPTu methods, it is necessary to clarify the discrepancy between these two methods. To this, this paper collects the high quality records of close by CPTu-SPT pairs at several sites in Taiwan to investigate the influence of data resolution of CPTu on the assessed liquefaction potential and further calibrates the discrepancy of liquefaction potential indices (LPI) assessed by the two methods. The results show that the influence of data resolution of CPTu is not significant on LPI. The calibration results as well as the corresponding transformation model could be a valuable reference to attain the consistency between LPI assessed by these two methods. © 2021, Chinese Institute of Civil and Hydraulic Engineering. All right reserved.