Experimental Study on Penetration Simulation of the Wellhead Suction Pile in Deep-Sea Resource Drilling

The suction pile well construction technique is increasingly adopted in deepwater drilling projects. The soil–structure interaction mechanism during the penetration and installation of the wellhead suction pile in clay is complex. Given the critical demand for precise installation outcomes in engineering practice, the influence of penetration velocity on installation performance requires significant consideration. Through scale-model experimental methods, various penetration velocities were configured primarily by adjusting suction pump flow rates. The influences of these velocities on penetration resistance, penetration depth, and related metrics were systematically assessed. A case study was conducted based on the engineering parameters of a wellsite in the South China Sea. A theoretical algorithm for WSP penetration resistance was developed and subsequently refined through experimental data. Coefficient optimization was established via theoretical assessment of strain-rate dependency and experimental data calibration. The optimized algorithm demonstrated strong agreement with field measurements, achieving a coefficient of determination (R2) exceeding 0.9. Compared to conventional theoretical approaches, it incorporated explicit consideration of penetration velocity. The analysis indicates that in soft clay, the penetration resistance of wellhead suction piles exhibits significant sensitivity to penetration rate, increasing with higher velocities. The influence of penetration rate on penetration depth is relatively weak. This computational approach offers design guidance for installation procedures and enables the implementation of the suction pile well construction mode in the South China Sea.