Eccentric Reinforced Concrete Beam-Column Connections Subjected to Cyclic Loading in Principal Directions

摘要

The authors tested five planar reinforced concrete (RC) comer beam-column connection assemblies; this type of connection could perhaps also be referred to as an exterior RC connection without a floor slab or spandrel beams. In all specimens, the column and the beam themselves were identical in design, except for the framing direction of the beam with respect to the rectangular-shaped column and the degree of eccentricity between the beam and column centerlines. Thus, the overall connection strength resulting from beam hinging (which all specimens developed) was very similar across all of the specimens, and therefore, so was the maximum joint shear demand imposed during testing. The specimens, however, eventually underwent different failure mechanisms due to the aforementioned test variables. When comparing the two concentric connections (WO and SO) with only different column orientations, the specimen loaded in the weak direction of the column (WO) exhibited some strength degradation while the specimen loaded in the strong direction (SO) did not. Specimen WO had a smaller effective joint area (by roughly 17%) than that in Specimen SO, according to ACI 352R-02, whereas the effective joint area was identical in the two connections per ACI 318-05. In addition, a more limited development length was available in Specimen WO for the hooked longitudinal beam bars because of the smaller column depth. Accordingly, Specimen WO exhibited more joint damage than Specimen SO during the tests.