5.1.3 Coupling Beams
The stirrups in all coupling beams are spaced at d/2 or less and are anchored into the core with hooks of 135 degrees or more.
For buildings designed and constructed in accordance with the 1989 or later editions of Part 2, Title 24, the evaluator may consider this condition as mitigated, and no calculations are necessary. The deficiency is in the strength of the coupling beams. Assume that the beams yield. Calculate their end-moment capacity based either on flexural yield or shear capacity, whichever is lower. The coupling beam moment capacity should include the contribution of a reasonable portion of the adjacent floor slab reinforcement when this reinforcement is in tension. Analyze the walls as independent walls with these restoring moments or shears helping to stabilize the walls. Check the stability of the wall and the stresses in the vertical boundaries. Conforming buildings which fail this check shall be placed in SPC 4, and no calculations are necessary.