Study On Cracking Resistance Of Cement Fly Ash Stabilized Macadam Base

At present,the problems such as poor uniformity,low early strength and easy crack resistance of cement stable class and two gray stable class in high grade road surface have seriously hindered the construction of highway in China.The cement fly ash stabilized crushed stone with the advantages of water stability gravel and two ash stabilized gravel has good technical ability.But the study of this kind of material is still not enough system,the lack of targeted technical standards,and according to the cement stabilized macadam and lime-ash stabilized macadam experience to guide the cement mixing ratio and fly ash stabilized macadam aggregate gradation design,causes the construction process of material consumption difference is very big,therefore,cement fly-ash stabilized class in promoting the process of struggling.Under the condition of guarantee strength,the damage phenomenon of cement stabilized class and two ash stable base is more common.In order to improve the performance of the road,vibration stirring technique is used to improve its strength and crack resistance.Vibrating mixing technology is a kind of building material can obviously improve mixing quality and efficiency of mechanical reinforcement technology,but the current vibratory mixing technology research focuses in terms of ordinary concrete,The relationship between the maximum dry density of the heavy crushed stone and the heavy compaction of the solid crushed stone was as follows:(1.04~1.05)rho gravity type compaction;the strength range of the base was 2 ~ 4MPa;At the same time,it is found that the vibration mixing technology can effectively improve the strength of the water stabilized macadam with the same dosage of cement,and the strength of the test piece formed by the vibration agitation of the low dose cement is larger than that of the high dose of the cement.The dry temperature shrinkage performance of the cement fly ash stabilized macadam base(water mud +fly ash =7%)is better than that of the cement.Cement stabilized macadam base.Therefore,in the case of the same strength,vibration mixing can effectively reduce the amount of cement,at the same time it can reduce the cracking phenomenon of the water stabilized macadam base,and improve the uniformity of the mixture at the base of construction.It is worth popularizing in practical engineering.