Research On Pavement Performance Of Cement And Fly-ash-residue Stabilized Crushed-stones

Currently it is the peak of road construction in our country while most of them are lack of construction materials and construction funds. How to minimize the ecological damage, reduce project cost and save investments becomes a universal, critical issue. In recent years, fly-ash-residue, which was always treated as solid waste, has been investigated for comprehensive utilization purpose due to environment protection and the increasing contradiction of energy supply and demands. This paper researched cement fly-ash-residue in stabilizing broken-stone performance, relying on Chongqing science and technology projects "research on fly-ash residue for the trunk highways and rural road".Fly-ash-residue is a kind of fly-ash, of which one or more than one property does not meet the specification requirements including particle size, sulfur proportion, loss on ignition, active ingredients. Basing on extensive laboratory testing abouy physical and chemical properties for Qijiang An-wen fly-ash-residue, lots of items are systematically researched in this paper regarding broken-stone stabilization performance of cement fly-ash- residue, such mix proportion, pavement performance, strength formation mechanism and economy are systematically researched. Studies show that fly-ash-residue can be directly involved in the conventional fine aggregate gradation adjustment. The effect of cement fly-ash-residue to stabilize broken-stones achieves the same strength level when its content reaches 30% or 35%, and it can reduce about 1% of cement, effectively improve the growth of strength, reduce the shrinkage rate, improve the crack resistance and water stable performance. At the same time, theoretical calculations and laboratory compaction tests are used to compare the maximum dry density, and found that experiment result about the maximum dry density is very close to the one coming from theoretical calculation when content of fly-ash-residue is 30% or 35%, theoretically verify the best fly-ash-residue rate is reasonable.The economic analysis results show that, 38 million Yuan can be saved if fly-ash-residue is used for basement for the proposed 600km Qijiang road. Also it can save the land required for spoil, protect the environment, reduce the waste of natural resources, which has significant economic and social benefits.