The Numerical Study of The Need for Transverse Reinforcement of a Spun Pile

Abstract

A numerical study based on FEA was conducted to seek the optimal need for transverse reinforcement of a spun pile with 400mm-diameter and 75mm of wall thickness. Two equations from ACI 318-19 and ASCE 7-16 were compared. The parametric study was limited to a spun pile with 450mm diameter and 75mm of wall thickness. The amount of transverse reinforcement was presented as the ratio to the ACI requirement. The ratio was varied and its effect on strength and ductility was observed. Three different axial load ratios, 0.1, 0.2 and 0.3 Fc’Ag, that are usually applied on the foundation were considered. The needs for spun pile with and without concrete infill are different since it is a function of the ratio of gross area (Ag) to the confined area (Ach) of concrete. An empty spun pile require a higher amount than the filled pile. The axial load ratio is another factors that affect the need for that reinforcement. However, ACI does not recognize it. The study found that the amount of transverse reinforcement required by ACI and ASCE can be reduced to get an economical amount without significantly reducing the strength and the ductility of the spun pile.