钢桥面SMA沥青铺装层应用优化研究

Study on Optimization of SMA Asphalt Pavement on Steel Bridge Surface

鉴于SMA沥青混合料近年来在正交异性钢箱梁桥面铺装层上的应用效果不是很理想,以及对国内已建钢箱梁桥面铺装层的分析研究,从混合料级配优化角度,试验室制作采用不同沥青改性剂、外加剂组合成的五种SMA沥青混合料,通过室内试验,确定每种方案的常规指标、车辙等路用性能指标,并结合复合梁疲劳试验结果进行对比分析,最终确定了最佳的沥青混合料组合方案。结果表明,高粘改性剂相对SBS改性剂有较好的路用性能,各种外加剂的选用对混合料的高温稳定性、耐疲劳性有较大提高。

SMA asphalt mixture has not received good effect on the pavement of orthotropic steel box girder reinforced bridge in recent years.Based on studying the pavement of the built steel box girder reinforced bridge,from the view of mixing material grading optimization,five SMA asphalt mixtures composing of different asphalt modifier and additive are adopted to determine their general indicators and pavement performance indicators such as track through indoor test.Comparison is carried out combined with composite beam fatigue test result.Finally the optimum asphalt mixture composition is determined.It is indicated that high-viscosity modifier has better performance for pavement compared to SBS modifier.Each additive largely improves high temperature stability and fatigue durability of asphalt mixture.