The behavior of the joints governs the collapse mechanism without any significant damage of reinforced precast concrete beams and columns. Vertical threaded bars were observed to yield and fail in shear and prominent concrete cracking was detected in the corbels (Fig. 13), while the other components did not exceed the yielding/ plastic condition. Figure 14 shows the hysteresis loops of key beam-column connections in terms of interstory force versus relative horizontal displacement of the beam at its top and bottom faces measured with respect to the centerline of the column in accordance with the instrumentation setup (Fig. 7). Despite the pin-ended configuration commonly assumed in the design process, the beam response resembled that of a double bending deformation and this mechanism more properly agrees with the experimental damage pattern.