| Semi-flexible pavement material is a new kind of composite pavement material, which is consist of asphalt concrete and cement grout. It has some features:high carrying capacity, high wearing resistance, high shear, high water stability and driving comfortable ability. Semi-flexible pavement material has very bright application prospects and it is suitable to use at intersection turner, gas station, parking, bus station, airport runways and other sections. However, the wild application of this material was impeded by the cracking problems. Therefore, it has an great significance to study the volume stability and the crack resistance of semi-flexible pavement.Relying on Hubei Provincial Communications Department project:" The durable multi-surface structure and material design of Wuying Highway of Hubei Province ", this article investigated and designed the matrix asphalt mixture and cement-based grout materials. It aimed at resolving the problem, which presents in the domestic and international technologies, the poor match of mechanical properties between cement-based grouting materials and asphalt mixtures, large differences in temperature sensitivity, poor interface bonding performance.The article proposed the merthod of material design, with high connectivity hole, high viscosity, and high thoughness of asphalt concrete. Using high viscosity modified asphalt and grading design optimization method, it also developed a high viscosity and high pore connectivity tough mixture PFC-13, which features are the sieve of mineral aggregate 4.75mm, pass rate of 10-25%, porosity of mixture 25-30%, the connectivity porosity up to 22-28%.The article investigated the interface compatibilizing modification mechanism of the asphalt and cement-based grout material. Using rubber powder, emulsified asphalt and polycarboxylate, it developed a highly flexible high-flow and high volume stability of cement paste:fluidity loss of less than 20%, segregation rate less than 2.5% points, the bleeding volume less than 3%, respectively,28d less than 0.3% shrinkage, elastic modulus less than 15324MPa, and asphalt adhesion greater than 4. The technology can easily solve the problem of the traditional segregation of cement paste, high elastic modulus, rapid loss of fluidity, and poor bonding properties of asphaltThe article studied the influence law of different asphalt, aggregate and cement based grouting materials on the volume stability, mechanical properties and crack resistance of emi-flexible pavement materials. We prepared high dimensional stability, high crack resistance of semi-flexible pavement material:thermal expansion coefficient to 3.4×10-5/℃, thermal shrinkage coefficient less than 1.2×10-5/℃, compressive strength greater than 7.6Mpa, compressive modulus for 2933 3600Mpa, shear strength greater than 5.74 Mpa, fatigue 12,000 times larger than life (stress ratio of 0.4). Compared with other semi-flexible pavement material at home and abroad, SMA, AC and other pavement materials, the development of this semi-flexible pavement has better performance, for example, low cost and easy construction, easy to solve the cracking technical difficulties, improving the road service life significantly and being of great prospects and values.
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