Study Of Crack Resistance On Cement Stabilized Macadam Base With Mixed Basalt Fiber

Cement stabilized macadam material has a series of advantage of high strength, stiffness and integrity, and is widely used in highway pavement base. But because of the cement stable macadam has the properties of dry and temperature shrinkage, when temperature and moisture content change, it is easy to generate shrinkage crack which becomes the main inducement of road early damage. In order to effectively reduce shrinkage deformation of cement stabilized macadam, and to improve the strength of cement stabilized macadam mixture, meanwhile, to restrain the shrinkage-cracking of cement stabilized macadam, adding basalt fiber in the cement stabilized macadam is put forward which forms new anti-crack of composite materials. We analyse the strength performance, stiffness properties, frost resistance and crack resistance of the composite material through laboratory test. The results shows that, when the volume quantity of basalt fiber is 0.6%o, it can effectively improve the mechanical strength of the cement stabilized macadam, decrease the stiffness modulus and improve frost resistance, which has an ideal effect of restraining drying shrinkage and temperature contraction of the cement stabilized macadam deformation; when the volume quantity is 0.6%o in the first 25 days, the shrinkage coefficient is decreased by 17.6% than ordinary cement stabilized macadam, temperature shrinkage strain is decreased by 25% than ordinary one. Based on studies in the laboratory test, as well as the 200m test road done in section A2 of Qiqihar to Gannan highway, the thesis summarizes the construction technology about mixed basalt fiber of the cement stabilized macadam base, makes the investigation and analysis on the test road of coring, and further proves that mixing basalt fiber has obvious effect which can enhance strength of the cement stabilized macadam base materials and restrain shrinkage crack.