Equivalent frame analysis for effective wall width of nonplanar beam–wall connections

Shear wall–frame structural systems are the most commonly used structural forms in tall buildings. In this structural system, many nonplanar beam–wall connections are formed by frame beams connecting to a shear wall in their out-of-plane direction. Few studies on nonplanar beam–wall joints have been conducted. This paper presents an investigation of the mechanical performance of nonplanar beam–wall joints based on the equivalent frame model assumptions. The concept of the effective wall width is introduced, and an analytical model is derived by considering the rotational stiffness of a beam–wall joint. The proposed effective wall width model is verified by experiments and finite element analyses. Comparison of the proposed model with the existing models shows that all the key design variables that affect the effective wall width in nonplanar beam–wall connections, in particular the cross-sectional dimensions of beams and shear walls, have been appropriately included in deriving the proposed model based on structural mechanics. The applicability and accuracy are demonstrated by a design example. It is shown that the proposed analytical model of the effective wall width for nonplanar beam–wall connections provides a simple and effective, yet accurate, means of analysis for the coupling effect of nonplanar coupling beams in tall buildings.