Diagonal tension strength of vintage unreinforced clay brick masonry wall panels

An experimental program was implemented where wall panels were obtained from two existing vintage unreinforced clay brick masonry (URM) buildings and subjected to a diagonal compression loading condition in order to induce a diagonal tension failure mode. The principal aims of the experimental program were to establish the diagonal tension strength of the vintage clay brick URM walls present in the two buildings and to establish a benchmark mortar mix suitable for use when manufacturing replica clay brick test assemblages that adequately represent the strength characteristics present in vintage URM buildings. It was concluded that the use of recycled clay bricks acquired from vintage URM buildings and a mortar mix of 1:2:9 (cement:lime:sand) appropriately replicates the material strength characteristics that are present in existing vintage clay brick URM buildings located in New Zealand.

► The diagonal tensile strength of vintage New Zealand unreinforced clay brick masonry was assessed. ► A total of eight masonry wall panels, being approximately 1.2 m × 1.2 m in size, were tested in diagonal shear. ► The test data supplemented the scarce database of in situ results obtained from existing vintage clay brick URM buildings. ► Recycled clay bricks and 1:2:9 (lime:cement:sand) mortar mix approximates shear strength in existing vintage URM buildings.