BIM-based approach to conduct Life Cycle Cost Analysis of resilient buildings at the conceptual stage

摘要

All costs within the life cycle of a building are known as its life cycle cost (LCC). In the design process of a building, the use of a lower initial cost index to select an option among others with similar performance may not lead to an economically optimal alternative during the life cycle. Hence, today, building designers and investors require a tool to estimate life cycle cost at the conceptual design stage to select an economically efficient option. Resilient solutions generally lead to a higher level of complexity and upfront costs and carry additional embodied environmental impact as well. This study aims to support the design of resilient buildings using a sound LCC methodology in the preliminary design stage. The research aims to integrate LCC capabilities directly into a Building Information Model (BIM) and increase the economical relevance and scientific robustness of LCC indicators towards better LCC cost optimization. The plugin, which is developed in the BIM tool is represented to use cost and resiliency factors to predict the whole process cost of building projects to assist designers in selecting a cost-efficient and resilient design option. The LCC of a building includes its initial cost, repair and maintenance cost, operating cost and salvage value at the end of the building's useful life, and all of which were considered in the estimation. The earthquake expected failure and human fatality cost are calculated to consider the resiliency index in building design. The application of the proposed framework to design a residential building is developed and validated on two design options. The application of the actual building project illustrates that by increasing the initial cost in the second alternative by 4.6%, its annual expected failure cost is decreased by 35.4%, and its total life-cycle cost is reduced by almost 10.4% within the first 45 years of operation. The reduction in the cost of the building and human fatality due to failure during an earthquake means the building's resilience would be improved. Using the developed plugin, designers could estimate LCC of the buildings at the early design stages and design more resilient buildings with better economic performance in its life cycle according to the proposed indices.