Abstract
This study aims to develop an environmental impact assessment methodology for concrete. Firstly, we discussed the environmental burden factors of concrete, which should be considered and are able to be assessed, and their inventory methods, and proposed an integrated assessment method of environmental impacts for concrete. Then, 15 kinds of embodied energy and emission intensity data, and 9 types of environmental impact intensities I1~I9) that consider different environmental burden factors were calculated for 36 kinds of raw materials of concrete, concrete mixing, and 5 types of transportation, by using Bottom-Up Method, and on basis of the modified version (LIME2) of LIME (Life-Cycle Impact Assessment Method Based on Endpoint Modeling), respectively. Finally, the environmental impact indexes (EII) of 6 series of fly concrete were calculated by using 4 kinds of the environmental impact intensities (I1, I6, I8, I9). The calculating results show that (1) recycling does not always decrease the environmental impact of concrete, unless recycling method is suitable; (2) the EII using the I6 that integrates the environmental impacts of 15 kinds of burden factors, would rationally evaluate the environmental impact of concrete. However, the EII using the I6 that was obtained by subtracting the environmental burdens of recycled wastes' disposal can clearly reflect the environmental benefits of recycling.
