水泥混凝土桥面加铺罩面层间剪切疲劳性能研究

Research on Interlayer Shear Fatigue Performance of Overlay on Cement Concrete Bridge Deck

摘要:

为探究水泥混凝土桥面加铺超薄罩面层间抗剪切疲劳性能的影响因素，采用改性乳化沥青、SBS改性沥青、基质沥青作为黏结层制备了组合结构试件。通过层间剪切疲劳试验分析了不同黏结材料、不同基面处理方式和环境温度对层间剪切疲劳性能的影响。结果表明：不同黏结材料的层间抗疲劳性能有明显差异，相同基面上SBS改性沥青的抗疲劳性能优于改性乳化沥青和基质沥青。相同应力比下SBS改性沥青间剪切疲劳寿命约为改性乳化沥青的1.4倍，约为基质沥青的2倍。水泥混凝土喷砂、拉毛以及露石处理后组合结构试件的疲劳寿命分别提高了17.0%～25.2%、24.5%～28.6%、34.5%～44.8%，其中露石对抗疲劳性能的提升效果最明显。温度对层间疲劳性能影响显著，环境温度越高，黏结层抗剪切疲劳性能越弱。

Abstract:

In order to explore the influencing factors of the interlayer shear fatigue resistance of the ultra-thin overlay on the cement concrete bridge deck, the combined structural specimens are prepared by using the modified emulsified asphalt, SBS modified asphalt and matrix asphalt as the binder layer. The effects of different binder materials, different base surface treatments and surrounding temperatures on the interlayer shear fatigue performance are analyzed through the interlayer shear fatigue test. The results show that the interlayer fatigue resistance of different binder materials is significantly different. On the same base surface, the fatigue resistance of SBS modified asphalt is superior to that of modified emulsified asphalt and base asphalt. The interlayer shear fatigue life of SBS modified asphalt under the same stress ratio is about 1.4 times that of modified emulsified asphalt and about 2 times that of matrix asphalt. The fatigue life of the combined structural specimens after the cement concrete sandblasting, brushing and exposed stone treatment increases by 17.0%~25.2%, 24.5%~28.6%, and 34.5%~44.8%, respectively, in which the exposed stone has the most obvious effect on the fatigue resistance. The temperature has a significant effect on the interlayer fatigue performance. The higher the ambient temperature, the weaker the shear fatigue resistance of the bonding layer.