Evaluation Method for Composite Bearing Performance of Pile Anchor Foundations in Layered Soil

• • The V-H load envelope is a reliable criterion for identifying uplift and lateral sliding failure modes in pile anchors, with a 95% confidence level in predicting failure mechanisms under combined loading. • • Positive bending moments significantly reduce uplift capacity; a 10% increase in moment leads to a 15% decrease in uplift resistance, highlighting the critical role of mooring point eccentricity in design. • • The NGI-ADP model accurately simulates anisotropic undrained shear strength of clay, with a 20% improvement in failure load prediction compared to traditional Tresca criteria. • • The finite element model with 256,815 elements achieves convergence within 2% error, providing a validated numerical framework for assessing pile anchors in layered soil with complex load combinations.