Feasibility of rammed earth constructions for seismic loads in Australia

Out-of-plane bending tests were conducted to determine whether rammed earth (RE) walls, designed to satisfy the thermal performance requirements specified by the Building Code of Australia, will satisfy the seismic loading requirements. A 2.4 m tall by 1.2 m wide full-scale insulated RE wall comprised of two 175 mm thick leaves separated by a 50-mm thick layer of insulation, was tested and the results were compared to that of a solid 300-mm thick RE wall. Both walls remained stable after cracking up to displacement of 50 mm (over 20% of wall thickness). The acceleration necessary to generate the initial forces to cause cracking was over 0.77 g, well in excess of the maximum design accelerations for face-loaded masonry walls in Australia. Furthermore, it was found that the flexural strength of the insulated cavity RE wall was simply the sum of the flexural strengths of the two leaves and that both walls after reaching their peak strength and cracking at mid-height responded as two rigid rocking blocks.Xiang Dong, Michael Griffith and Veronica Soebart