CPT Based Design Method for Horizontal and Vertical Capacity of Piles Installed by the Rotary Cutting Press-in Method

The Rotary Cutting Press-in (RCP) method, which employs both vertical static jacking force and torque, has been developed to extend the applicability of the traditional press-in method, which relies solely on jacking forces. This enhancement is particularly beneficial for harder ground conditions. Several SPT (Standard Penetration Test) based design methods have been developed for estimating the vertical and horizontal bearing capacity of RCP piles. However, in recent years, the development of CPT (Cone Penetration Test) based design methods has gained momentum because CPT tests can provide continuous and detailed subsurface information. In this paper, a CPT-based method is proposed to estimate the horizontal capacity of piles using a lateral soil resistance and displacement model known as p-y analysis. Additionally, the axial capacity of RCP piles is estimated based on a newly proposed method, which has been obtained by adjusting an existing CPT based framework for the RCP piles. The performance of the proposed CPT based methods is evaluated and compared to that of API and SPT-based methods using the results of a series of field tests and large-scale model tests.