Effects of asphalt emulsion on the durability of self-compacting concrete

Abstract

Asphalt emulsion (AE) is the alternative raw material for self-compacting concrete (SCC), some researchers have reported on the composition design, workability, and strength properties recently. But few attempts have be made on the durability. For a better understanding on the effects of AE on SCC durability and its microscopic mechanism, the SCC specimens were prepared with various AE contents, and the self-compacting workability was confirmed via slump flow test. Then, three kinds of durability tests were performed to evaluate the chloride-penetration resistance, frost resistance and sulfate-corrosion resistance, and the scan electronic microscope (SEM) test and X-ray diffraction (XRD) test were performed to discuss the microscopic mechanism. The results show that the chloride-penetration resistance, frost resistance and sulfate-corrosion resistance of SCC were enhanced by adding AE. Observed from SEM test, the interfacial transition zone (ITZ) of SCC is mainly filled with the C-S-H gel and AE, and the SCC microstructure tends to be compact, resulting that the concrete durability was improved by using appropriate AE. However, the excessive AE may lead to more pores in SCC because of the retardation effect on cement hydration. The AE with the content of 10% given the most desirable effect for durability.