Research on Mixture Component Design of “Skeleton-dense” Cement Fly-ash Stabilized Aggregate

Abstract

Coarse and fine aggregate gradation limitation, ingredient proportion calculation method and formula parameter testing method for “skeleton-dense” cement fly-ash stabilized aggregate mixture design were presented. On the basis of research above, cement fly-ash stabilized aggregate which contains 4% cement, 11% fly-ash, and 85% aggregate was designed, then the samples were made to compare its compressive strength, temperature shrinkage coefficient and dry shrinkage coefficients to those of suspending-dense cement stabilized aggregate and “skeleton-dense” cement stabilized aggregate with the same cement content through lab experiments. The results show that (1) coarse aggregate in “skeleton-dense” cement fly-ash stabilized aggregate designed according abovementioned calculation method can reach dense status easily after compaction, and coarse aggregate in the mixture can form good skeleton structure; (2) the 28 d and 90 d unconfined compressive strengths of “skeleton-dense” cement fly-ash stabilized aggregate are better than the corresponding performance of “suspend-dense” and “skeleton-dense” cement stabilized aggregates; (3) “skeleton-dense” cement fly-ash stabilized aggregate has less temperature shrinkage coefficient and dry shrinkage coefficient.