|
Title |
A Model for Lifecycle CO2 Assessment of Building Structures Considering the Mixture Proportions of Concrete
|
|
DOI |
https://doi.org/10.4334/JKCI.2014.26.2.201 |
|
Keywords |
전과정 CO2 ; 배출 ; 포집 ; 콘크리트 구조물 ; 성능평가표 lifecycle CO2 ; emission ; uptake ; concrete structure ; performance table |
|
Abstract |
The present study proposes a phased model to assess the lifecycle CO2 amount of concrete structures. The considered system boundary is from cradle to recycling, which includes constituent material, transportation, batching and mixing in ready-mixed concrete plant, use and demolition of structure, and crushing and recycling of demolished concrete. The CO2 uptake of concrete by carbonation during lifetime (40 years) of a structure and the recycling life (20 years) after demolition is estimated using a simple approach generalized to predict the carbonation depth from the surfaces of concrete element and recycled aggregates. Based on the proposed phased model, a performance evaluation table is realized to straightforwardly examine the lifecycle CO2 amount of concrete structures. The proposed model demonstrates that the contribution of ordinary portland cement (OPC) to lifecycle CO2 emission of the concrete structure occupies approximately 85%. Furthermore, the CO2 uptake is estimated to be approximately 15～18% of the lifecycle CO2 emissions of concrete structures, which corresponds to be 19～22% of the emissions from OPC production. Overall, the proposed CO2 performance table is expected to be practically useful as a guideline to determine the CO2 emission or uptake at each phase of concrete structures.
|