Retrofitting aged masonry buildings using advanced cementitious fibre reinforced concrete material: case study and comparison to traditional methods

China has a large stock of existing aged buildings that can no longer meet the needs of modern life and need to be reinforced to improve their seismic resistance. Complete demolishing and rebuilding waste resources while retrofitting and reusing are more sustainable. However, residents feel reluctant to invest in retrofitting their dwellings, even with government funding, because of its high cost. Previous research has mainly focused on upgrading heating, ventilation, air conditioning (HVAC), and lighting to benefit from energy-saving and carbon emission reduction without considering holistic renovation requirements. On the other hand, traditional retrofitting techniques were widely reported in the literature worldwide to improve structural integrity, load-bearing capacity, and seismic performance. However, little research has been conducted on the cost-effectiveness of different retrofitting methods, especially the emerging methods involving more advanced construction materials, such as highly ductile fibre-reinforced concrete (HDC). To fill this gap, this study compared two retrofitting plans for an aged masonry building. Satisfying various renovation requirements, the retrofitting plan utilising HDC led to a nearly 32% reduction in cost and approximately 36% reduction in construction time when compared to traditional renovation methods. The building information modelling (BIM) tools helped calculate quantities and improve stakeholder communication efficiency.

Key words: Cost estimation / retrofitting / highly ductile fibre reinforced concrete (HDC) / building information modelling (BIM)