Similitude of 1/3-scale Concrete Masonry Units for System- Level Seismic Behavior Studies

The objective of this effort was to investigate the similitude between assemblages and components constructed from full-scale and 1/3-scale concrete block, mortar, grout, and reinforcing steel. This study serves as a preliminary investigation to the testing of a complete 1/3-scale partially grouted, lightly reinforced concrete masonry building for seismic resistance. This effort is motivated by the lack of reliable data on the system-level seismic response of such buildings, which is becoming increasingly relevant due to the adoption of the International Building Code (and particularly the seismic provisions) in the Eastern US. This paper discusses the manufacturing process of the 1/3-scale concrete block through the use of a recently acquired small-scale block making-machine at Drexel University. In addition, this paper will report comparisons between an extensive assemblage testing program, which included over 200 specimens and investigated compression, bed-joint shear, and diagonal tension strengths and failure modes. Results include comparison of quantitative response quantities and statistical significance, qualitative descriptions of behavior, and various FE modeling studies undertaken to help interpret the experimental results.