Abstract: In this paper, in view of the large planar concavity of a high-rise commercial apartment building, Midas Gen software is used to carry out dynamic analysis under frequent/rare earthquakes for three plane treatment schemes, i.e., weak coupling beam, strong coupling beam and anti-seismic slab. The calculation results show that, since only small earthquake elastic conditions are considered in the general seismic design, when the concavity is small and meets the limit requirements of the code, adding tie beam at the groove can remarkably improve the seismic performance; when the planar concave degree is large, adding tie beam is not very ideal; the effect of adding anti-seismic slab is obviously better than that of only adding tie beam; neither tie beam nor anti-seismic slab can greatly reduce the torsional displacement ratio and effectively solve the inherent torsional irregularity of concave irregular structures. For such planar concave irregular structures, while the plane is strengthened, the structure should have sufficient torsional stiffness to avoid excessive torsional effect.

Key words: planar concave frame-shear wall structure , torsional , irregular seismic design