Research On Storage Stability Of The Emulsified Asphalt Using For Prime Coat

Emulsified asphalt using for prime coat is a kind of asphalt production. Emulsified asphalt has many advantages, so it has been used extensively in road building as a new construction material. <Standars specification construction and acceptance of highway asphalt pavements>(JTG F40—2004) expressly provided that it must lay 5¹0mm asphalt overlay on the roadbed. So the good performance emulsified asphalt has a broad application prospect and economic value.In this thesis, the effects of the emulsifier content, pH value and stablizeis on the storage stability were discussed, and it successfully developed a kind of emulsified asphalt with good stability.The effects of emulsifier content on storage stability was studied. There were three kinds of emulsifiers, including an quaternary ammonium salt cationic emulsifier(QA60), the sodium dodecyl sulfate emulsifier(SDS) and OP-10.The particle size distribution and Zeta potential was investigated, and the effects of the amount of emulsifier on the storage stability were discussed. As the result showed that the optimum content of the QA60 was 1.6 wt%, the optimum content of the SDS was 2.0wt%, and the optimum content of OP-10 was 4.0wt%.The effects of pH value on stability was discussed by investigating the particle size distribution and Zeta potential. The experiment showed that pH value has an obvious influence on storage stability, and different kinds of emulsifiers have different optimum pH value. Moreover, the optimum pH value for QA60 was 4, for SDS was 11¹2, for OP-10 was 6⁹.Effects of different stablizers on the storage stability were discussed by investigating the Zeta potential and normal viscidity of the quaternary ammonium cationic(QA60)emulsified asphalt. As the results showed, CaCl₂, Al₂(SO₄)₃ and NH4Cl have the main effect on Zeta potential to increase the stability, and Sodium carboxymethyl cellulose(CMC) has the different influence on normal viscidity to improve it. Moreover, when mix-use of both CaCl2 and CMC, the storage stability is better than using the single one.