Usually, most of beam-column joints in a reinforced concrete (RC) building are concentric, as in the case when beam and column axes are in the same plane. For architectural reasons, however, it is not uncommon construction of eccentric beam-column joints in the exterior frames of RC buildings. In eccentric beam-column joints, the axis of the spandrel beams is offset from the axis of column. As for these eccentric joints subjected to earthquake loads, it was considered that additional shear forces, produced by torsion moment from beams, severely act on the joints. Moreover, brittle shear failures of eccentric joints subjected to additional shear forces were observed from the previous earthquake damages. In order to investigate the effect of eccentricity on degradation of shear strength, stiffness and deformation capacity of beam-column joints, non-linear analyses using a three-dimensional finite element method (3-D FEM), which is very useful to get the rational solution of 3-D stress conditions, have been carried out in this study. Reference specimens for this 3-D FEM analysis were selected from the previous experimental study. Reference specimens failed in joint shear failure after beam flexural yieldings in the tests. The FEM results show a good agreement with the test results on the maximum story shear forces and the failure modes. When the beam flexural yieldings have occurred, the maximum story shear forces did not increase. Moreover, in order to understand the shear transfer mechanisms in an eccentric beam-column joint, the internal stress flows of both concentric and eccentric joints obtained from analytical results were discussed in detail. In spite of the same maximum story shear forces, it was recognized that the internal concrete stresses concentrated severely to the eccentric side in a joint.
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