Summary

This report, ""Stiffness of Low Rise Reinforced Concrete Shear Walls"", was prepared by the Working Group on the Stiffness of Concrete Shear Wall Structures of the ASCE Dynamic Analysis Committee. The purpose of this paper is to review the methods currently used to compute the in-plane stiffness of low aspect ratio reinforced concrete shear walls used in nuclear power plant structures and to recommend a position. After exploring the industry practice of using the strength of materials approach to compute shear wall stiffness, a comparison is made to experimental data on large scale model shear walls available in the literature. This comparison indicates that there are differences between measured stiffness values and those calculated by common industry methods. From this examination, a consensus on how to calculate the stiffness of low aspect ratio reinforced concrete shear walls is developed. The recommendation is to use two concrete in-plane stiffness estimates to bound the effect on in-structure response spectra due to lateral loading.