Seismic Testing of Autoclaved Aerated Concrete Shearwalls: A Comprehensive Review

Abstract

Autoclaved aerated concrete (AAC) is a lightweight cementitious material that has recently been introduced into the United States construction market. This article reports on the first phase of a comprehensive research program that has recently been carried out to propose design provisions for autoclaved aerated concrete (AAC) and to develop the technical basis for those provisions. The first phase of the program addressed extensive testing on AAC shearwalls, which are the fundamental lateral force-resisting elements of AAC structural systems. The 19 shearwall specimens were made of a variety of AAC elements, including masonry-type units and reinforced panels, laid either horizontally or vertically. The aspect ratio of the specimens (ratio of height to base length) varied from 0.6 to 3, and each specimen was designed to fail in either shear or flexure. Based on the test results obtained at The University of Texas at Austin and elsewhere, the authors developed reliable procedures and corresponding provisions for the design behavior of AAC shearwalls as governed by flexure, shear, and other limit states. Flexural cracking was observed in two directions in 15 shearwall specimens, with a resulting limiting value of tensile bond strength between leveling bed mortar and AAC of 50 psi based on a lower 20% fractile. Flexure-shear cracking was observed in seven shearwall specimens, and web-shear cracking was observed in 13 shearwalls.