Properties And Environmental Impact Assessment Of Foamed Asphalt For Warm Mix Asphalt

The warm mix technology of mechanical foaming can not only reduce the temperature, but also does not need additional additives. For these reasons, the technology has drawn more and more attentions in the development of road research in china. But, during the application process of warm mix technology, researchers still use the design method of hot mix asphalt, which lacks targeted performance verification methods and uniform design specifications of warm mix asphalt. The paper puts forward the design method and performance verification apply to foam warm mix pointedly on the research basis of foam warm mix asphalt mixture.First, the paper explore the foaming principle of modified asphalt and select three parameters to study foaming effect of the modified asphalt, the three parameters includes asphalt temperature, foaming water consumption and water temperature, then regulate and select from test data, fit out the second order mathematical model in interaction of different foaming parameters.Then do response surface analysis under analysis of variance meet the demand of significance level, draw three d response surface analysis diagram, select the foaming parameter at the time of getting best foaming effect.Second, the paper researches the design method of foam temperature mixing modified asphalt mixture, maturity the mixture ratio design process of the bubble warm mix asphalt Sup - 20, analyzes the raw materials, grading option, asphalt content, workability and compactibility of mixture, verifies the best foaming water and mixing temperature of the mixture through the mixture workability test, determines foam molding temperature of warm mix asphalt mixture through the mixture compaction test.Finally, in order to quantitatively evaluate the environmental benefits of the foam warm mix asphalt mixture, the paper sets up the whole life cycle LCA evaluation index and frame work based on the research of whole life cycle assessment (LCA) method, and does the research and analysis in the process of whole life cycle, including raw material production phase construction operation phase maintenance stage,and energy consumption emissions during finally abandoned stage. Through the collection of whole life cycle’s data and field measurements of the construction site, the paper quantify the whole life cycle environmental impact of foamed warm mix asphalt mixture, and analyses the data’s reliability of the environmental impact assessment, the conclusion is that foam warm mix technique has significant environmental and economic benefits...