Grouted bar-in-conduit connections are versatile connections widely used in the precast concrete construction. In precast load bearing wall structures, two vertical wall panels are connected by a reinforcing bar, which is projected from one panel and grouted into a sleeve placed in the other. The main function of the ties is to resist tension induced by in-plane and out-of-plane straining actions and to provide ductility to the wall assembly through the yielding of the reinforcement. Limited information is currently available on the behaviour of such connections. This paper presents the findings of an investigation conducted to investigate the behaviour of grouted reinforcing bar connections and their failure mechanisms. The bond strength was evaluated using a pull-out test on a bar extended from a grouted sleeve specimen. The test parameters of the study were the bar surface condition (deformed and smooth) and the embedded length (6, 12 and 36 diameter-of-bar (d_b)). A total of eight specimens were tested to failure under direct tensile loads and the slip of the bars was recorded. Results indicate that an embedment length of 6db allowed the bar to yield, but bond failure dominated in the strain hardening zone. It was also observed that an embedment length of 12d_b was sufficient to mobilize the tensile capacity of the bar, after which an increase in the grouted sleeve length resulted in no additional capacity.
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