Material property testing for the refurbishment of a historic URM building in Yangon, Myanmar

The architecture of Yangon, Myanmar has been heavily influenced by British colonisation from the mid-1800s, with a large portion of the historic building stock being constructed of unreinforced masonry (URM). The city’s historic buildings have regularly been exposed to the ravages of war and natural disasters, as well as low levels of maintenance despite a rapidly growing population. One of the primary needs when assessing a building for refurbishment and/or retrofit is to characterise the constituent material properties. On-site material investigation was undertaken in a large historic building originally constructed in (circa) 1896, with multiple renovations and expansions made at different times. The original structure is comprised of unreinforced loadbearing Laterite stone and clay-brick masonry walls. In-situ testing and sample extraction were conducted at 14 discrete test locations throughout the building and consisted of: (i) bed joint shear tests in clay-brick masonry with 16 tests throughout the building; (ii) in-situ deformability (aka ‘flat-jack’) tests on the Laterite stone masonry and on the clay-brick masonry; (iii) laboratory compression tests and petrographic examinations of individual clay-bricks, Laterite stones and mortar samples. The findings from the materials characterisation are presented herein with the aim of serving as guidance for engineers assessing similar historic buildings in Myanmar and other Southeast Asian countries, where few characterisation studies on local, historic materials – particularly on Laterite stone masonry – have been publicized