Research On Application For Low Active Fly-ash On Road Case In Chongqing

The application research of fly ash in china's highway construction have many years,and the technique has more mature. Fly ash in highway construction mainly used for semi-rigid base, semi-rigid base in highway construction is most commonly used by base or subbase in nation and chongqing,with strength and stiffness of the big advantages,but the problem is that shrinkage cracks still troubled the engineering in hihgway. Chongqing's fly ash is lower activity, so it is very a few application in highway construction, and the result is that local environment was polluted. The papers relying on Yusui gravel project, the application research in semi-rigid base for Chongqing Luohuang Power Plant and Chongqing Power plant by contrast Xi'an Baqiao fly-ash.Papers presented the use of fly-ash in base at home and abroad; through the analysis for the activation principle of fly ash, because the fly-ash of Chongqing area has lower activity generally, so to stimulate the activity of fly ash with variety of methods. Their are several methods to excite the activity of fly ash, Such as through lime, lime and ativator A, cement, cement and lime , cement and ativator A etc, so as to do binder material strength test. Select a appropriate proportion of cases with cement mixing, and select the best proportion with lime and ativator A.To evaluate several aggregate gradation by Bailey method. Select appropriate gradation as aggregate gradation for mixture road performance in verification test. By void design procedure to design different mixture. For the same gradation of aggregate, lime and fly ash mixture used in close the gap filler aggregate, cement and fly ash mixture with different reserved voidage to design the mixture. Also, by the experiments of mechanical performance (unconfined compression strength, the cleavage strength), Anti-brushing performance and Anti-cracking performance (thermo-contraction , dryness-contraction), and through comprehensive analysis of the fly ash to decide the way of fly ash in semi-rigid application. The paper by using the fundamental method of grey system theory, to evaluate the mixture of the road performance, for the fly ash application in high-grade road for Chongqing area provides a strong basis.