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End-of-life analysis for brick debris: recovery, strength, life cycle cost and environmental assessment

Üçer Erduran, Deniz
There exists a vast stock of masonry buildings in the world, yet, some of them are being demolished and disposed of; owing to the changes in building bye-laws, redundancies of buildings; and clearing the plots for new and mostly taller buildings. Either demolition or deconstruction is preferred; huge amounts of masonry-based waste are accumulated in the end. On the other end, since these buildings are not always demolished due to wear and tear, the condition of masonry walls after demolition may still be of a good quality that may be conducive to their use elsewhere. Thus, recovery of these materials not only helps to salvage the old materials but also contributes to environmental sustainability, as well as carrying the historical value of the building by integrating these materials into the new design. This study investigates state-of-art about rules and regulations, recovery proposals, usability & physical properties, environmental and economic assessment of demolition of masonry buildings and salvaging methods for their debris. Accordingly, two buildings i.e. a historical load bearing solid brick masonry building in Russia and a concrete framed, hollow brick infill building in Turkey were chosen to monitor their demolition processes and determine the eventual condition of debris. It was observed that large vi wall sections with load bearing solid bricks from the historical building as well as the hollow brick wall pieces from the the reinforced concrete contemporary building could be reused by using various techniques to clean, cut and prepare them for integration into new wall construction. Mechanical properties obtained from compression, flexure and shear tests on few samples exhibited higher values than allowable limits in the standards; which is conducive in terms of materials reuse. Additionally, digital models of these recovery methods showed lower environmental impacts in terms of human health, ecosystem quality, climate change and resources in comparison to the new walls, when simulated in SimaPro Life Cycle Assessment software. In contrast to the promising results (for reuse) obtained from strength tests and environmental impact simulations; the costs of the proposals for reuse are higher than the construction with new materials. This is due to the fact that cutting and shaping of the debris brings extra cost to the recovery process. In conclusion, although the reuse of salvaged material was determined as advantageous from the point of view of environmental and social aspects of sustainability, the economic aspect has disadvantages that can be overcome by better recovery and salvaging methodologies. Hence, more efficient and cost reducing processes need to be investigated.