Research On The Performance Of Semi-rigid Roadbase With Fly-ash From Qianbei Power Plant

In the highway construction of our country at present, the semi-rigid material is widely used for its high intensity, low cost, and being wide of the raw material source.The Qianbei power plant is located in Bijie of Guizhou province, and it has made important contributions to the local economy development. But its long-term running have brought a lot of solid waste-fly ash, usually it is dealed with landfill. As the fly ash is very fine granular, under the wind blowing it usually cause air pollution or dust blowing; Under the erosion of rainwater it will cause water pollution; And as the fly-ash is alkaline, when it is used as fertilizer additives, will cause the alkalization and compaction of land, reduce the fertility. In order to properly dispose the fly-ash of Qianbei power plant, in this subject we will study on the fly-ash as road construction materials, inspect the pavement performance of semi-rigid base which is mixed into the fly-ash from Qianbei power plant.Lime and fly-ash stabilized crushed-stones base is one typical semi-rigid base, has a long history of application. We have accumulated a wealth of design and construction experience, and have established a sound evaluation system.Lime and fly-ash stabilized crushed-stones base has made great contributions to the highway construction in the past few decades in China. However, its inherent problems such as lower early strength, serious shrinkage are always existent. Compare with lime and fly-ash stabilized crushed-stones ,as a new type of semi-rigid base, the cement and fly-ash stabilized crushed-stones has many characteristics, such as early-strengthening, high strength, less cracks and early-opening to traffic. Besides, it also has drastic growth in post-strength and benefits in supporting the increasing transportation, especially to the heavy loading transportation.According to laboratory tests and theoretical research, the physical and mechanical properties, chemical indicators of the fly ash are detailedly analysed; Systematically study the pavement performance of lime and fly-ash stabilized crushed-stones and cement and fly-ash stabilized crushed-stones which are mixed fly-ash from Qianbei power plant, include mechanical performance, stability performance and shrinkage performance. Combined with these performances bring out the best mix scope, and make detailed comparison of pavement performance between the two types. Throught analyse the formation process of Strength and shrinkage principium of the semi-rigid roadbase-skeleton dense type cement(lime) and fly-ash stabilized crushed-stones, bring out the influencing factors of Strength formation and shrinkage; Provide guidance for the application of fly-ash from Qianbei power plant in semi-rigid roadbase.