Numerical study of low confinement spun pile to pile cap connection

Abstract

The numerical study has been conducted to investigate the behaviour of spun pile – pile cap connection based on the common practice in Indonesia. The piles manufactured in Indonesia have low confinement where the amount of transverse reinforcement is less than 20% than the minimum requirement set by ACI 318-19. The research objectives are to study the parameters that affect the behaviour of that connection. Three parameters investigated are: the connection details, the effect of concrete infill and the amount of transverse reinforcement. The typical connection of spun pile and pile cap in Indonesia is considered adequate and can perform as fixed connection since slip at connection region was not detected in the FE analysis. The embedment length is adequate to develop yield strength of the prestressed wire. By filling the hollow with the concrete it increases the connection strength by 15% whereas the strength improves more than 50% by adding 6D19 reinforced bar. Adequate confinement improves the performance of the connection at peak post-stage that affects ductility.