Shake Table Testing of Posttensioned Concrete Masonry Walls with Openings

Abstract

The in-plane seismic response of posttensioned concrete masonry walls with openings is investigated by means of shake table testing. A test program was initiated to verify the seismic performance of a wall system for use in residential construction. Two single-story in-plane wall tests were conducted initially to study the effect of door and window openings. This led to the construction and testing of a simple square structure which investigated the influence of multiple door and window openings and wall corners. All walls were posttensioned using unbonded high-tensile steel bars which allowed the wall panels to rock at the wall-foundation interface. Wall damage consisted of masonry crushing in the lower wall corners and vertical cracking under the openings and in the lintels. Residual displacements were minimal, due to the restoring forces provided by the posttensioning tendons. A complete description of the test setup and results is provided, including discussion on wall structural response in terms of flexural strength, displacement capacity, deformed shape, and damage patterns.