Nonlinear Interaction of RC Frame‐Wall Structures

The nonlinear interaction phenomenon in reinforced concrete frame‐wall systems in the presence of combined vertical and lateral loading is studied for a range of values of the four parameters, such as the ratio of beam and column stiffness, the ratio of column and shear wall stiffness, the slenderness ratio of columns, and the proportion of lateral to vertical load (load ratio). The method used for this study is based on finite element techniques and takes into account both material and geometric nonlinearities. The method uses the noni linear stress‐strain curve of the constitutive materials and does not use bilinear or trilinear idealizations. The important conclusions which have emerged from this study are as follows: (1) Nonlinear behavior is significantly pronounced in the frame‐wall systems with stiff walls when under a large load ratio; (2) the bracing effect of the shear wall is more effective for the case of frames having slender columns and flexible beams when under a large ratio of lateral to vertical load; (3) nonlinear idealization of the flexural characteristics of shear walls is important when the shear walls are connected to stiff frames; and (4) stiff walls undergo more reduction in their stiffness at failure than flexible walls.