Asphalt content and combined aggregate gradation in reclaimed asphalt pavement are detected; Marshall test is carried out to determine the optimum asphalt content and mixing proportion of asphalt mixture AC-20 by central plant hot recycling; additionally, wheel rutting test and freeze-thaw splitting test are conducted to verify the mix design. Compressive resilience modulus of the mixture with different RAP percentages are tested by MTS-810 at 15 ℃ and 20℃; splitting strength of the mixture with different RAP percentages are determined by Marshall tester at 15℃; beam-bent fatigue test of the mixture is carried out by UTM. The results show that with the increase of RAP percentage, compressive resilience modulus and splitting strength of asphalt mixture by central plant hot recycling go up meantime; both the intercept and slope of fatigue equations diminish, signifying the gradual decline of the mixture's anti-fatigue property. 1 850 -2 250 Mpa and 1 250 -1 550 Mpa are recommended as compressive resilience modulus of the mixture at 15 ℃ and 20 ℃ respectively; 2. 0 - 2. 6 Mpa is recommended as splitting strength of the mixture at 15℃. Taking advantage of the modified fatigue equations in power function form, allowable tensile strains of the mixture with different RAP percentages can be calculated in structural design of recycled asphalt pavement.%检测了回收沥青路面材料(RAP)中沥青含量与矿料合成级配,通过马歇尔试验确定了厂拌热再生沥青混合料AC-20最佳沥青用量及配合比,并通过车辙试验与冻融劈裂试验加以验证；采用MTS-810材料测试系统测试了该混合料15,20℃时不同RAP质量分数的抗压回弹模量,采用马歇尔试验仪测试了该混合料15℃不同RAP质量分数的劈裂强度,采用多功能材料试验系统(UTM)对该混合料进行了小梁弯曲疲劳试验.结果表明:随着RAP质量分数的增加,厂拌热再生沥青混合料抗压回弹模量、劈裂强度均有所提高,疲劳方程截距和斜率减小,抗疲劳性能下降；在进行厂拌热再生沥青路面的结构设计时,推荐该混合料在15,20℃的抗压回弹模量分别为1 850～2 250,1 250～1 550 MPa,15℃的劈裂强度为2.0～2.6 MPa；利用幂函数修正后的疲劳方程,可计算混合料不同RAP质量分数的容许拉应变.
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