In-situ seismic verification of non-structural components of unreinforced masonry buildings

Abstract An experimental campaign was developed to evaluate the response of non-structural elements of unreinforced masonry buildings for simulated earthquake loads. Eleven walls within 4 URM properties were subjected, in situ, to uniformly distribute static loads applied using a system of airbags. The buildings were located in Darlington, a suburb of Adelaide, South Australia. Three of them were built in the 1960s and the fourth was built in the 1980s. Accompanying material tests were done in situ and in the laboratory, enabling a comparison to be made between the old buildings material strength and the default material strengths recommended in the Australian Masonry Standards, AS3700. Tests were also conducted on 3 URM chimneys to establish their failure mechanism and strength. A highlight of this research is the findings that existing masonry chimneys are vulnerable to a ‘design earthquake’ in Australia. The results also suggest that despite masonry material strength being significantly lower than the code default values, the walls satisfied expected seismic force demands. The reasons include the beneficial effects of in situ wall boundary conditions on out-of-plane wall strength.

[1]  Michael C. Griffith,et al.  Simulation of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (I): Displacement-based Approach Using Simple Failure Mechanisms , 2016 .

[2]  Michael C. Griffith,et al.  Seismic assessment of out-of-plane loaded unreinforced masonry walls in multi-storey buildings , 2014 .

[3]  Nelson Lam,et al.  Cyclic testing of unreinforced masonry walls in two‐way bending , 2007 .

[4]  Nelson Lam,et al.  Displacement‐based seismic analysis for out‐of‐plane bending of unreinforced masonry walls , 2002 .

[5]  John Kariotis,et al.  State-of-the-Art Report on Seismic Performance of Unreinforced Masonry Buildings , 1995 .

[6]  Michael C. Griffith,et al.  Performance of Unreinforced Masonry Buildings During the 2010 Darfield (Christchurch, Nz) Earthquake , 2010 .

[7]  B. Taranath Seismic Rehabilitation of Existing Buildings , 2004 .

[8]  Michael C. Griffith,et al.  Out-of-plane flexural strength of unreinforced clay brick masonry walls , 2005 .

[9]  Michael C. Griffith,et al.  The Demise of the URM Building Stock in Christchurch during the 2010–2011 Canterbury Earthquake Sequence , 2014 .

[10]  Michael C. Griffith,et al.  Geometric characterisation and out-of-plane seismic stability of low-rise unreinforced brick masonry buildings in Auckland, New Zealand , 2014 .

[11]  Michael C. Griffith,et al.  In Situ Out-of-Plane Testing of As-Built and Retrofitted Unreinforced Masonry Walls , 2014 .

[12]  Jaroslav Vaculik Unreinforced masonry walls subjected to out-of-plane seismic actions. , 2012 .

[13]  Guido Magenes,et al.  Out-of-plane shaking table tests on URM single leaf and cavity walls , 2016 .

[14]  Jason Ingham,et al.  In situ out-of-plane testing of unreinforced masonry cavity walls in as-built and improved conditions , 2015 .