| With the development of road discipline, the strength of semi-rigid base are basically able to meet the traffic demand. However, before the use of life, most of the road in our country have appeared serious structural damage. The reason for asphalt surface reflective cracks caused by semi-rigid shrinkage crack become an urgent problem to be solved. Although there are extensive research literature about base shrinkage cracks home and broad, at the same time, we have taken various measures to solve asphalt surface reflective cracks caused by base shrinkage, but the base cracks have a worsening trend. We suspect that the road have produced a large number micro-cracks during constructing period. Such deficiencies in addition to the repeat of vehicle load and temperature, the crack gradually extended , until the formation of reflective cracking.In this paper, under the two conditions of room temperature and change temperature, we test material of curing period and after curing period. The analysis is the differences of material of curing period and after curing period: First, the material strength is gradually improving, and the ability to resist shrinkage stress are raising; second ,the material response to consume part of the free water , the water loss rate can not reflect this section of water , at the same time it also can cause shrinkage stress.This paper mainly relate to: first , the design of anti-cracking grade macadam; second, according to the contrast of shrinkage texts on material in curing period under room temperature, shrinkage tests on material curing for 28d under room temperature, shrinkage tests on material in curing period under variable temperature and shrinkage tests on material curing for 28d under variable temperature, depth analysis the impact on the shrinkage properties for the changes of material in curing period. Third, according to test analysis of wrap and not wrap after curing period, recommended the construction process which can resistance to cracking.
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