Shear strength and cracking behavior of reinforced concrete nonstructural walls

Recent Japanese earthquakes have severely damaged the nonstructural walls of many buildings. While nonstructural walls do not influence the seismic performance of a building, this damage can still sometimes cause buildings to be demolished or render their continued use impossible. Therefore, it is important that seismic designs take the seismic properties of nonstructural walls into consideration. Shear loading tests and FE analysis were conducted to investigate this phenomenon, which showed that shear strength decreased and crack width increased with wider rebar spacing. The FE analysis indicated that the discrete crack model evaluated the test results more adequately than the smeared crack model. In addition, the stress distribution was localized with wider rebar spacing. Therefore, it is thought that the shear strength decreased. Finally, a simple crack width prediction method was proposed. With this method, the rebar strain was calculated using the horizontal deformation of the walls. Using this method, the crack width could be reasonably estimated. It is believed that these findings will be useful for designing nonstructural walls with improved seismic performance.