Geometric characterisation and out-of-plane seismic stability of low-rise unreinforced brick masonry buildings in Auckland, New Zealand

The 2010-2011 Canterbury earthquakes and corresponding Royal Commission reports have resulted in changes to the legislative environment and led to increased public awareness in New Zealand of the earthquake performance of unreinforced masonry (URM) buildings. As a result, building regulators, owners, tenants, users and heritage stakeholders will be facing a unique challenge in the near future where assessments, improvements and demolitions of URM buildings are expected to occur at an unusually high rate. Auckland is the largest city in New Zealand and because of the relative prosperity of Auckland during the period 1880-1935 when most URM buildings were being constructed in New Zealand, the city has the largest number of URM buildings in the country. Identifying those buildings most at seismic risk in Auckland’s large and varied building stock has warranted a rapid field assessment program supplemented by strategically chosen detailed assessments. Information that can be procured through rapid field inspections includes the building geometric typologies (e.g., heights, building footprint geometry and isolated versus row configuration), elevation type (e.g., perforated frame versus solid wall), wall construction (e.g., solid versus cavity, number of leaves) and basic construction material type (e.g., clay brick versus stone). Furthermore, investigation into the architectural history, heritage status and functional usage of Auckland’s URM buildings will affect the direction of retrofit strategies and priorities. As the owner of a large and varied portfolio of URM buildings as well as the local organisation responsible for assessing building safety, Auckland Council is developing exemplar inspection, assessment, prioritisation and retrofit strategies that will target the seismic risks associated with URM buildings, in particular, so as to preserve and enhance safety and the economic and community value of these special buildings. Collaboration amongst Auckland Council, The University of Auckland and GNS Science has resulted in a state-of-the-art rapid quantitative assessment program applied to a sampling of typologically representative URM buildings in Auckland.Walsh, KQ ; Dizhur, DY ; Almesfer, N ; Cummuskey, PA ; Cousins, J ; Derakhshan, H ; Griffith, MC ; Ingham, J

MOF-801/Graphene Adsorbent Material for Greenhouse Climate Control System—Numerical Investigation

Greenhouses with efficient controlled environment offer a promising solution for food security against the impacts of increasing global temperatures and growing water scarcity. However, current technologies used to achieve this controlled environment consume a significant amount of energy, which impacts on operational costs and CO2 emissions. Using advanced metal organic framework materials (MOFs) with superior water adsorption characteristics, this work investigates the development of a new technology for a greenhouse-controlled environment. The system consists of MOF coated heat exchanger, air to air heat exchanger, and evaporative cooler. A three-dimensional computational fluid dynamics (CFD) model was developed using COMSOL software and experimentally validated for the MOF-801/Graphene coated heat exchanger (DCHE) to determine the best cycle time and power input. It was found that using desorption time of 16 min and power input of 1.26 W, the maximum water removal rate was obtained from MOF-801/Graphene of 274.4 g/kgMOF/W.hr. In addition, an overall mathematical model for the greenhouse climate control was developed and used to investigate the effects of air humidity and velocity on the input air conditions to the greenhouse. Results showed that with high relative humidity levels of 90% in the greenhouse can be conditioned to reach the required relative humidity of 50%

Effect of vinyl acetate effluent in reducing heat of hydration of concrete

Waste generation especially in surface coating industries is a potential pollutant to the environment globally. Waste disposal in the form of recycling or reused has gained some recognition as a raw material in many kind of interested fields. This study is therefore, aimed at utilizing Vinyl acetate effluent generated from manufacturing process of paint as polymer modifier in concrete. The research highlights the influence of Vinyl acetate effluent on setting time and control of heat of hydration in concrete. Three specimens containing 0%, 2.5% and 5% of Vinyl acetate effluent by weight of cement were prepared in cubic moulds. The temperature rises due to heat of hydration in all mixes were recorded. Finding shows that incorporating Vinyl acetate effluent considerably delayed the setting time in cement paste and reduced the total temperature rise in polymer modified concrete. Therefore, addition of Vinyl acetate effluent polymer in concrete may improve the properties of concrete to some extent particularly in mass concrete production