This paper presents the results of an experimental investigation carried out to investigate the seismic performance of a two storey brick masonry house with one room in each floor. A half-scale building constructed using single wythe clay brick masonry laid in cement sand mortar and a conventional timber floor and timber roof clad with clay tiles was tested under earthquake ground motions on a shaking table, first in the longitudinal direction and then in the transverse direction. In each direction, the building was subjected to different ground motions with gradually increasing intensity. Dynamic properties of the system were assessed through white noise tests after each ground motion. The building suffered increasing levels of damage as the excitations became more severe. The damage ranged from cracking to global/local rocking of different piers and partial out-of-plane failure of the walls. Nevertheless, the building did not collapse under base excitations with PGA up to 0.8g. General behaviour of the tested building model during the tests is discussed, and fragility curves are developed for unreinforced masonry buildings based on the experimental results.Keywords: Unreinforced masonry, seismic performance, shaking table test, fragility curves 1.Introduction Unreinforced masonry (URM) is the most common form of building construction in many countries. In developing countries, such houses are commonly conceived by the owners without following any engineering design principles and are constructed by local masons without following code-recommended practice. Even in developed countries, any URM buildings existing nowadays were most likely designed and constructed several decades ago when the seismic design philosophy was in its infancy. As a result, most URM buildings fall well short on the yardstick of modern seismic design requirements.URM buildings have suffered severe damage, in many occasions leading to collapse, during medium to large earthquake shaking; thereby resulting in significant loss of life and property. Increasing interest in the last few decades has resulted in many experimental tests on URM sub-assemblages [1-5] and on complete URM buildings [6][7][8][9][10][11][12]. These studies have provided significantly valuable insights into seismic performance of URM buildings. However, many characteristics of URM buildings, such as seismic performance of URM gable walls and clay tiles as roofing materials, are yet to be fully understood. The lack of understanding of URM buildings is further compounded by diversity in its construction, its non-engineered nature and non-standard design [13][14][15], regional differences in construction materials and techniques used, and age of the buildings.To understand the dynamic behaviour and to develop simplified fragility curves of a general class of URM buildings that are representative of houses in New Zealand, a one-half scale model of a two-storey brick house with flexible floor and roof has been constructed and tested on a shaking table under simulated e...

The 8th October 2005 Kashmir Earthquake was one the largest earthquakes in Northern Pakistan in its recorded history. It caused an unprecedented level of damage and destruction in Pakistan Administered Kashmir (PAK) and the North Western Frontier Province (NWFP). It damaged or collapsed more than 0.6 million buildings - leaving 3.5 million people shelter less as winter approached. A large part of the earthquake-affected area is difficult to access and highly snow-prone, with rugged terrain and scattered settlements. It posed unique challenges and efforts on a massive-scale for reconstruction. For residential buildings, the Pakistan government adopted a house-owner driven approach. The reconstruction policy stated that the government and other agencies would provide equal technical assistance and subsidy to each family, without differentiating between who lost what. To increase capacity in earthquake-resistant construction, large-scale training of artisans, technicians, engineers, and community mobilisers has been conducted. Campaigns to “build back better” have raised awareness in the communities. Local Housing Reconstruction Centres have been established for training, advice, and dissemination of earthquake-resistant technology. This decentralised approach has helped in achieving reconstruction smoothly. This paper will present the authors’ first-hand experience in the reconstruction effort, and the opportunities and unique challenges faced.

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Nepal is one of the most earthquake-prone countries in the world, and at the same time is one of the most economically deprived. On 25 April 2015 mid-western Nepal was hit by the devastating Gorkha earthquake measuring Mw 7.8 with the epicentre located 76 km north-west of Kathmandu. The earthquake was followed by a series of aftershocks, with the most significant occurring on 12 May 2015 with Mw 7.3 and an epicentre located north-east of Kathmandu. The earthquake and the associated aftershocks resulted in the destruction of half a million buildings, leaving millions of people homeless and causing a loss of more than $3.5 billion (USD) to the housing sector alone. Approximately 9,000 people were killed and over 23,000 people were injured - mostly due to damaged or collapsed buildings. A number of documents have been published pertaining to general observations following the 2015 Gorkha earthquake and aftershocks. Here the common building typologies and related failure modes observed during inspection surveys by the authors who were part of the various reconnaissance teams following the earthquakes are summarised. A brief background on the 2015 Gorkha earthquake is provided with an outline of the tectonic environment and seismological background of Nepal and a brief summary of previous earthquake activities in the region is presented. Common construction practices identified during the reconnaissance are illustrated and briefly explained to provide context to the observed earthquake damage, with an emphasis placed on unreinforced masonry (URM) building typologies and construction practices. Comparisons between URM building damage and published macro-element failure modes are provided using various photographic and schematic examples. Commonly observed failure modes and potential causes of failure are also highlighted for buildings constructed of reinforced concrete (RC) frames with masonry infill. A brief review of adopted temporary shoring techniques is also included.