Optimization of the method for calculating the uplift bearing capacity of helical anchors in Nantong silt strata

Abstract

A numerical simulation approach was adopted to investigate the uplift bearing characteristics of helical anchors in Nantong silty sand and to predict their uplift bearing capacity. Finite element model validation was performed, and the uplift bearing mechanism of helical anchors was analyzed. The current code’s uplift bearing capacity calculation formula was optimized, and the accuracy and reliability of the modified formula were evaluated. The results indicate that the critical embedment depth ratio of the anchor plate in Nantong silty sand is 5, and the critical spacing ratio ranges from 3 to 4. The current code’s formula underestimates the uplift bearing capacity of helical anchors under these conditions. To improve the prediction accuracy, the optimization coefficients M and L, which account for the embedment depth ratio of the anchor plate, are introduced, and fitting formulas for these coefficients are provided to improve the prediction of uplift bearing capacity in Nantong silty sand and to serve as a reference for similar engineering applications.

Keywords

silty sand / helical anchors / uplift bearing characteristics / finite element analysis / formula optimization

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Funding

The National Natural Science Foundation of China(52378329)