Microstructure and formation process of the material mixed with anticracking agents were observed by the scanning electronic microscope. It is found that the anticracking agent has expansion character and can make the material dense. Through the shrinkage tests, it is proved that the shrink spaces of the road base, which is caused by the variations of the temperature and humidness, decrease apparently because of the anticracking agent. The influence of delaying the molding time on the strength of gravel mixtures is also analyzed and it is concluded that anticracking agent has slow setting performance. On account of adding anticracking agent into the semirigid base material, early strength of the material is enhanced, curing period is shorten and lasting quality is improved, which can be showed from the durability test. The continuous constructions of the base and asphalt pavement are feasible in the test road because of anticracking agent, which make the base and surface pavements compacted tightening. Thus, cracking of the pavements can be restrained, durability of the road can be improved and road life can be extended.