Drift Capacity of Reinforced Concrete Structural Walls with Special Boundary Elements

Performance of reinforced concrete (RC) walls in recent laboratory tests and in recent strong earthquakes has revealed that thin wall boundaries are susceptible to concrete crushing, reinforcing bar buckling, and lateral instability. To address this concern, a wall database with detailed information on more than 1000 tests was assembled to enable the study of the impact of various parameters on wall deformation capacity. For this study, the data are filtered to identify and analyze a dataset of 164 tests on well-detailed walls generally satisfying ACI 318-14 provisions for special structural walls. The study indicates that wall deformation capacity is primarily a function of the ratio of wall neutral axis depth-to-compression zone width (c/b), the ratio of wall length-to-compression zone width ([l.sub.w]/b)), wall shear stress ratio ([v.sub.max]/[square root of (term)][f'.sub.c], and the configuration of boundary transverse reinforcement. Based on these observations, an expression is developed to predict wall drift capacity with low coefficient of variation. Keywords: compression zone width; cross-sectional aspect ratio; drift capacity; overlapping hoops; structural wall; wall shear stress.