Comparison of the seismic response of reinforced auger pressure grout and concrete columns

• Testing columns made of reinforced auger pressure grout and reinforced concrete.
• Conducting cyclic tests and hybrid simulation tests with and without axial-load.
• Presentation of both global and local response of the test specimens.
• The results imply load-bearing members made of grout are suitable in seismic zones.
• The hybrid simulation tests justified the adequacy of auger pressure grout columns.

Despite the wide use of grout as a structural material due to easy construction and cost-effectiveness, its seismic performance has rarely been evaluated experimentally. In particular, reinforced grout columns which may experience significant lateral deformation need experimental evidence to validate their adequacy. This paper summarizes findings from a relevant experimental study, which consists of five cyclic tests and one hybrid simulation test conducted at the University of California, Berkeley. The results show that reinforced auger pressure grout columns under cyclic lateral load and high constant axial load can provide ductile and reliable behavior in flexure, comparable to that of similarly configured reinforced concrete (RC) columns. Therefore, these reinforced grout columns can be considered as an adequate alternative to RC columns subjected to medium to high compressive axial loads in regions of high seismicity.