Title: Shear Strength of Lightly Reinforced Wall Piers and Spandrels

Author(s): Kutay Orakcal, Leonardo M. Massone, and John W. Wallace

Publication: Commentary Reference

Volume:

Issue:

Appears on pages(s): 455-465

Keywords: friction; pier; reinforced concrete; shear; spandrel; strength; wall.

DOI:

Date: 7/1/2009

Abstract:
Between the 1950s and 1970s, a significant number of buildings were constructed using lightly reinforced perimeter walls with openings. Evaluation and rehabilitation of such buildings requires accurate assessment of the expected shear strength, stiffness, and ductility of the wall segments (wall piers and spandrels) that comprise the primary lateral load-resisting elements. Assessing wall shear strength is complicated by factors such as use of a single curtain of distributed reinforcement, lack of hooks, and use of weakened plane joints, which are all common in older construction. To address these issues, a database of existing test results was assembled and reviewed; and tests were conducted on lightly reinforced wall piers and spandrels to address significant gaps in the available test data. Observations indicate that the amount of boundary reinforcement provided, presence of axial load, and the location of a weakened plane joint on the wall are the most important factors in the assessment of nominal shear strength.