EXPERIMENTAL INVESTIGATION ON FLEXURAL BEHAVIOR OF INNOVATIVE CONCRETE FRAME JOINT ASSEMBLED WITH PRECAST PRESTRESSED CONCRETE BEAM

All course loading tests of four cross-shaped beam-column joints specimens were conducted under the positive or negative bending moment． Diverse layouts of PVC sleeve were considered as an impact on the joint performance． According to the current design code，ultimate bearing capacity，maximum crack width and deflection were calculated，and the results showed that the flexural bearing capacity of a precast joint was basically the same as that of a cast-in-situ joint． In serviceability limit state，the experimental results of maximum crack width and deformability agreed with those of the calculation，and they both could satisfy the design specifications． The arrangement of sleeves at the beam end could effectively reduce the stress peak on the top of beam and improve the anti-cracking property． It is considered that fewer sleeves would be better if there was no crack of concrete on beam top in the pretensioned zone．