A Critical Appraisal of Seismic Cone Penetration Testing

Abstract

Abstracts The Seismic Cone Penetration Test (SCPT) is widely considered the most reliable tool to determine the in-situ Small Strain Shear Modulus (Gmax) profiles. These profiles can then be used as direct input to design models for e.g., offshore windfarm foundations. However, although SCPT has been performed routinely on land for many years, the complexities of performing this kind of testing with a seismic source located on the seabed and the subsequent data analysis presents ongoing challenges for the industry. The lack of standardization of the equipment used for the test, the set-up on the seabed, the data obtained during the test and the methods for interpretation can easily lead to difficulties for practicing engineers to establish the reliability of the generated data sets, and thus the analysis outcome. The authors provide a critical review of the acquisition methods commonly utilized and how these affect the quality of the acquired data and the derived results. An appraisal of the advantages and disadvantages of true interval straight ray path and pseudo interval true ray path processing methodologies is presented along with alternative recommendations for developing design vs profiles.