Research on Crack Resistance of Lime-flyash-cement Stabilized Macadam

Through experimental research of basic mechanical properties,comparative study of the strength properties of semi-rigid base materials including lime-flyash-cement stabilized macadam was carried out.Through study of the indices of water loss rate,dry shrinkage strain and shrinkage coefficient,dry shrinkage performance of lime-flyash-cement stabilized macadam and other semi-rigid base materials was analyzed.By regression analysis,the relation of accumulative dry shrinkage amount with time and accumulative water loss rate was got.Through temperature shrinkage test,the relation between temperature shrinkage coefficient and temperature range was studied,and the relation between average temperature shrinkage coefficient and maximum temperature shrinkage coefficient was researched.The results show that(1)when cement admixture dosage of lime-flyash-cement stabilized macadam is less than 2%,dry shrinkage performance and temperature shrinkage performance of lime-flyash-cement stabilized macadam are superior to those of cement-flyash stabilized macadam and cement stabilized macadam,but a little worse than those of lime-flyash stabilized macadam.It is suggested that the cement admixture dosage of lime-flyash-cement stabilized macadam is less than 2%,to improve the shrinkage performance of lime-flyash-cement stabilized macadam through early curing,and to evaluate the temperature shrinkage performance of lime-flyash-cement stabilized macadam using temperature shrinkage coefficient of 0～-10 ℃.