Effect of high-strength materials on lateral strength of stocky reinforced concrete walls

Stocky reinforced concrete (RC) walls with low height-to-length aspect ratios stand to benefit greatly from high-strength steel and concrete because the lateral load designs for these walls are governed mostly by strength, with reduced demands for ductility, which is compatible with the reduced strain capacities of high-strength materials. This paper numerically investigates the effect of these materials on the peak lateral strength of stocky walls for buildings and non-containment, safety-related nuclear structures. A nonlinear finite element method and available closed-form design equations for predicting the wall lateral strength are compared with existing experimental results, culminating in modeling and design recommendations. The validated finite element method is then used to conduct a parametric investigation on the effect of high-strength steel and concrete on the wall lateral strength, specifically focusing on rectangular walls without boundary regions/members. Ultimately, the paper demonstrates the benefits (and limits) of high-strength materials for these walls, and provides an impetus for future experimental research and inclusion of these materials in ACI 318 and ACI 349. Modifications needed to the current ACI methods to predict the lateral strength of stocky walls are also discussed.