CSB (Confined Socket Bolt) 전단연결재의 전단 성능 평가

Abstract

This study evaluated a shear capacity of confined socket-bolt (CSB) shear connector developed for utilizing cast in placed pile (CIP) as apermanent underground wall. The push-out tests were performed in the specimens with different CIP types, CSB shear connector types, , andconcrete compressive strengths of concrete pile, and with or without waterproofing at interfaces between CIP and underground wall. Test results showedthat the specimens with a H-shaped pile were fractured in the CSB shear connector, while the fracture concentrated in the concrete part of the specimenswith a reinforced concrete pile was alleviated as the compressive strength of the concrete pile increased, resulting in the severe fracture of CSB shearconnector. The maximum shear capacities of the specimens with high strength bolts and reinforcing bars used as CSB shear connector were approximately1.22 and 1.20 times higher than those of the specimens with a H-shaped pile, respectively, and 1.10 and 1.16 times higher than those of the specimenswith a reinforced concrete pile, respectively. Meanwhile, the maximum shear capacity was not significantly affected by the embedding length of theCSB shear connector and overlapping length of reinforcing bar. The predicted shear capacities calculated from the KDS standards were lower thanthe measured values of all specimens tested in this study.