Title: Development of alternative strength reduction factors for inter-wythe shear failure of precast concrete insulated wall panels
Date Published: March - April 2026
Volume: 71
Issue: 2
Page Numbers: 58 - 72
Authors: Margot Gregoire, Zoe N. Lallas, Matthew J. Gombeda, Chaimaa Jaafari, and Jamshid Mohammadi
https://doi.org/10.15554/pcij71.2-03

Abstract

This paper details the development of alternative strength reduction factors that capture the behavior and variability of precast concrete insulated wall panels failing in interwythe shear at the peak flexural resistance limit state. Previous research has shown that this milestone generally manifests when most wythe connectors in a panel are past their proportional limit, which introduces a greater level of uncertainty for the panel compared with the uncertainty during its elastic response. The methodology addressed three types of uncertainties: the reliability of assessments of the variability of wythe connector data against average values, the accuracy of simplified design backbone curves, and the effectiveness of beam-spring models to capture the behavior of panels. The results facilitated recommendations for new strength reduction factors as a function of plausible safety indexes. These factors were as high as 0.881 and 0.818 for discrete and continuous wythe connectors, respectively, when assuming a very lenient probability of failure of 0.1 and a corresponding safety index of 1.28.