Capacity Design of Coupled RC Walls

Capacity design is an important tool that enables controlled ductile response of structures when subjected to earthquakes. The need for specific capacity design requirements for walls coupled by deep coupling beams, however, is often overlooked and it is assumed in some instances that the same equations used for cantilever walls will give satisfactory results when applied to coupled walls. Furthermore, existing equations for capacity design incorporated into codes and design guides were developed a number of years ago and no longer represent the state-of-the-art. This research investigates the performance of existing capacity design equations for coupled walls and then proposes a new simplified capacity design method based on state-of-the-art-knowledge. The proposed method is then verified through a case study in which a set of 15 coupled walls were analysed using non-linear time-history analyses. Following this, an investigation is made into how the maximum shear force in an individual wall relates to the maximum shear force in the coupled wall system.