STUDY ON MECHANICAL BEHAVIOR OF SEMI-RIGID CONNECTION ON PILE HEAD FOR PRE-CAST CONCRETE PILES USING UNBONDED ANCHORS

Abstract

Recently, several methods have been developed to improve the performance of semi-rigid connections on pile heads by reducing the stress on pile heads and decreasing the cost of foundation works. This study was carried out as a part of research into the semi-rigid connecting method for pile heads on pre-cast concrete piles. This paper describes the mechanical behavior of the pile heads connected using un-bonded round steel bars with anchor plates. Full-scale loading tests and numerical analysis were carried out to estimate the complicated behavior of this type of connection. As a result, it was confirmed that the connection developed retains it's bending capacity at rotational angles of less than 1/20 radian. The prediction result based on the flexural analyses, which modeled the confined effect and non-linear stress-strain characteristics of the concrete, corresponded closely to the relationship between the bending moment and the rotation observed in the full scale tests.