EXPERIMENTAL STUDY ON THE SIZING EFFECT OF SHEAR BEHAVIOUR OF 3D PRINTED CONCRETE JOINTS

Abstract

Shear key plays a crucial role in structural stability and load transfer mechanisms, particularly in construction and civil engineering applications. With the advent of additive manufacturing, 3D printing offers a novel approach to fabricating intricate and customized shear key geometries. Existing studies have already explored the shear behavior of 3D printed joints; however, this research aims to study the sizing effect on 3D printed shear keys, thereby contributing potential optimization of materials and establishing groundwork for future research in this field of study. This study fabricated a total of six specimens, featuring two different angles. The objective is to investigate potential sizing effects in 3D printed concrete shear keys by comparing this study with existing research studies. Direct shear tests were conducted to analyze peak shear load and deformation, with comparisons drawn to existing experiments for evaluation. The test results showed that a bigger shear key angle has a higher average peak shear stress. Despite differences in strength among the specimens tested, the Shear Stress–Displacement curve displayed remarkable consistency and similarity in trend. The absence of a definitive conclusion regarding the sizing effect in 3D printed concrete shear keys stems from the lack of a consistent trend observed across both large and small specimens.