John M. Nichols 1 and Daniel P. Abrams 2

  1. Post Doctoral Researcher, 205 N Mathews Avenue, University of Illinois at UrbanaChampaign, 61801,
  2. Hanson Engineers Professor of Civil Engineering and Director of the Mid-America Earthquake Center, University of Illinois at Urbana-Champaign, 205 N Mathews Avenue, Urbana, 61801,


The Mid America Earthquake Center is a collaborative research center, established by seven participating core universities with funding from the National Science Foundation. The primary vision of the center is to reduce earthquake losses through research. Research at the Center is directed at improving seismic resistance through effective mitigation procedures. This results from the vulnerability of gravity-load designed buildings located in the eastern and central United States to an infrequent, but large future earthquake. A complementary program of research on earthquake resistant evaluation and rehabilitation for low-rise, unreinforced masonry buildings is underway at the MAE Center. This paper provides a summary of masonry-related research at the Mid-America Earthquake Center. It will include descriptions of experimental and computational research done to study seismic performance of unreinforced masonry building structures, and the effectiveness of various retrofit procedures. The summary will highlight:

  • Behavior of unreinforced clay-unit masonry walls and piers behaving in shear or flexure and retrofitted with shotcrete, FRP and ferrocement coatings, and reinforced cores.
  • Dynamic response of low-rise buildings with flexible floor diaphragms where dynamic stability of out-of-plane walls is a concern.
  • Behavior of timber floor diaphragms retrofitted with various means.
  • Three-dimensional behavior of a full-scale, two-story URM test structure subjected to simulated earthquake forces, and a corresponding half-scale replicate structure subjected to simulated earthquake motions.
  • Response modification procedures for seismic retrofit of URM low-rise buildings. Each description will include statements as to the relevance of the research for impacting structural engineering practice through the updating of seismic codes and guidelines for reducing losses resulting from future earthquakes in the central and eastern United States.

Key words: Masonry Testing, URM Building, earthquakes, Mid America