Evaluation of driving energy transferred to split spoon sampler for accuracy improvement of standard penetration test

Abstract

Uncertainties in the driving energy transferred to the split spoon sampler (Esampler) cause inaccuracies of the standard penetration test (SPT) N values. In this study, an energy monitoring module (E-module) is developed to evaluate Esampler and correct N. To demonstrate the application of the E-module, SPTs were performed at three study sites where the grounds are mainly composed of silty sands, and the transferred energy at the head of the driving rod (Ehead) and Esampler were evaluated. In addition, static penetration resistances were measured to validate the energy corrections of N. The experimental results and analyses indicate that the N corrected using Esampler exhibits an improved relationship with static penetration resistances compared with that corrected using Ehead because the Esampler directly affects the penetration of the split spoon sampler. Therefore, the evaluation of Esampler using the E-module and the correction of N may be used to obtain improved subsurface characterizations.