Probabilistic Pullout Capacity Analysis of Strip Anchors

Plate anchors have been recognized as a cost-effective and efficient solution for offshore applications. Conventional methods for predicting anchor pullout capacity often assume the soil is homogeneous with uniform properties. However, natural soils, particularly in offshore environments, typically exhibit significant spatial variability due to their geological history and formation process. To account for the inherent spatial variability, this paper conducts a probabilistic analysis of the pullout capacity of strip plate anchors embedded in both clay and sand using the Random Finite Element Method (RFEM) over a wide range of soil and anchor parameters. The soil undrained shear strength and friction angle are represented as random fields, and the mean and standard deviation of the anchor pullout capacity factor are estimated. The results show that while the soil correlation length has a minimal impact on the mean pullout capacity, it strongly influences the standard deviation. This indicates that understanding the spatial variability of soil properties is essential in order to achieve accurate anchor pullout failure probability predictions. Overall, the findings of this study can aid in the probabilistic analysis of anchor pullout capacity and guide the design of reliable plate anchors in spatially variable soils.

Keywords: Plate anchor, Pullout capacity, Spatial variability, Probabilistic analysis, Random finite element method, Clay, Sand.