布敦岩沥青湿法工艺掺量对 改性沥青混合料性能的影响

为研究采用湿法工艺布敦岩沥青掺量对改性沥青混合料使用性能的影响，采用70号A级道路石油沥青作为基质沥青，制备了最大掺量为基质沥青40%的布敦岩沥青改性沥青.进而采用石灰岩集料，对不同掺量改性沥青进行了AC-20C的沥青混合料马歇尔配合比设计.通过实验室试验，确定了不同掺量布敦岩沥青改性沥青混合料的车辙试验动稳定度、浸水马歇尔试验残留稳定度与冻融劈裂试验残留强度比、弯曲试验破坏应变、渗水系数，还有20 ℃、15 ℃抗压回弹模量、15 ℃劈裂抗拉强度.试验结果与结果分析表明，随着布敦岩沥青掺量的增加，改性沥青混合料的高温稳定性、水稳定性、抗渗性、刚度和强度均不同程度逐渐得到提高.随着布敦岩沥青掺量的增加，改性沥青混合料的低温抗裂性先提高至一峰值，然后略有回落.对于路用沥青混合料，推荐的布敦岩沥青掺量上限为基质沥青的30%.
In order to investigate the effect of proportion of buton rock asphalt on the performance of modified asphalt mixture with wet method，Penetration 70 Grade A petroleum asphalt was used as base asphalt for preparing the modified asphalt binder containing rock asphalt up to 40% of the base asphalt. Limestone aggregate was used in designing the AC-20C asphalt mixture of various percentages of rock asphalt by using Marshall method. Laboratory tests were carried out to determine the properties of the asphalt mixture modified with Buton rock asphalt. These properties include dynamic stability from rutting test， retained Marshall stability from immersion Marshall test， tensile strength ratio from freeze-thaw indirect tension test， failure strain from low temperature flexural test， water permeability coefficient from permeability test， compressive resilient moduli from compression tests at 20 ℃ and 15 ℃， and tensile strength from indirect tension test at 15 ℃. The test results and analyses indicate that with the increase of rock asphalt percentage，the high temperature rutting resistance， moisture damage resistance，permeability resistance，stiffness， and strength of the modified asphalt mixture improve gradually to varying degrees.On the other hand，with the increase of rock asphalt percentage，the low temperature cracking resistance of the modified asphalt mixture improves to a peak value and then falls back slightly.The recommended maximum percentage of Buton rock asphalt for paving asphalt mixture is 30% of the base asphalt.