Environmental Coordination Research Of Hith Performance Concrete Production Process

High Performance Concrete (HPC) is a new type of environment-friendly concrete with low water-binder ratio, high durability and large amounts of mineral admixtures. In this paper, the service life of concrete is studied using a Life Cycle Assessment (LCA) approach. Material flow analysis and environmental impact analysis method (CML) are used to analyze the material input and output situation of HPC production process and their environmental impact respectively.By HPC chloride permeability tests, the service life of HPC with different mineral content are predicted, concrete durability is analysis. The integrated environmental performance of HPC is analyzed based on the relationship between HPC durability and total environmental load, and the "Life-environmental load ratio" is proposed to be used as an integrated index of HPC environmental performence.As those mineral admixtures contain some components which can be harmful to the environment, the leaching toxicity and other environmental impact of mineral admixtures is test by experiment.The results show that: 1) in the HPC production process, hidden flow was the central part of total material requirements for about 87%, abiotic depletion potential, energy depletion potential, greenhouse gas and photochemical smog emissions are the major environmental impact of HPC; 2) HPC with mineral admixtures has a good durability, and composite mixing is more favourable to durability, and composite mixing of Fly ash 30%, Silica Fume 5% and Ground granulated blast slag 15% has the best capability of anti-chloride ions penetrating, the predicted service life of this HPC increase 2.8 times conteast to the concretes with no mineral admixtures; 3) after 50% cement was replaced by mineral admixtures, composite-mixing has a significant impact to the HPC service life but not so significant to the total environmental load; 4) by the "Life-environmental load ratio", the integrated environmental performance of composite mixing of Fly ash 30%, Silica Fume 5% and Ground granulated blast slag 15% is the best, which is 1.41×10^-2a, it is 3.85 times of the "Life-environmental load ratio" of concretes which with no mineral admixtures; 5) the mineral admixtures have no leaching toxicity, obvious impact to the envirment is high pH value of leaching liquids.