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为了对ERS钢桥面铺装体系的实际使用效果进行验证,本研究以嘉绍大桥项目为依托,采用路面加速加载系统对钢桥面铺装层的长期使用性能以及极端条件下的路用性能进行试验研究。试验发现,ERS和ERN两种结构轴载作用次数达205万次时,平均车辙深度增长的绝对值均不超过5 mm;试验加载次数超过130万次以后,两种桥面铺装结构基本不渗水,其抗滑性能也趋于稳定;加载次数超过80万次以后,铺装结构内部材料出现了疲劳损伤,弯拉应变出现明显增长,且横向最大拉应力大于纵向最大拉应力。而在高温湿热极端条件下,ERN结构在轴载作用次数达6万次时,超薄磨耗层开始出现推移剥落;ERS结构在轴载作用次数超过9万次后,SMA结构层迅速破坏。结果表明,ERS和ERN两种结构在自然条件下均未出现开裂或破损,具有优良的抗车辙性能;而在极端条件下,这两种结构都出现明显的滑移剪切破坏。相反,热固性的树脂沥青材料在极端条件下表现出了极佳的高温稳定性能,但其抗开裂性能有待进一步研究。横向拉应力引起的纵向裂缝是造成铺装层开裂破坏的主要原因,因此应将横向最大拉应力作为铺装层设计的重要控制指标。
In order to validate the actual use effect of ERS steel deck surfacing system, this study, based on the Jia Shao Bridge project, uses the pavement acceleration loading system to evaluate the long-term serviceability of steel deck surfacing and road performance under extreme conditions Conduct experimental research. It was found that the absolute value of average depth of rut growth did not exceed 5 mm when the number of ERS and ERN loads was 2.05 million times and that of the two kinds of bridge deck structures was basically not Seepage, the anti-skid performance also tends to be stable; After loading more than 800,000 times, the internal materials of the pavement structure appeared fatigue damage, the bending strain increased obviously, and the maximum lateral tensile stress was larger than the maximum longitudinal tensile stress in the longitudinal direction. Under extreme conditions of high temperature and humidity, the ultra-thin wear layer began to peel off when the number of times of axial loading was up to 60,000. When the number of times of axial loading exceeded 90,000 times, the SMA structure layer rapidly ruptured. The results show that both ERS and ERN have no rupture or damage under natural conditions and have excellent anti-rutting performance. However, under both extreme conditions, both of them show obvious slip shear failure. In contrast, thermosetting resin asphalt displays excellent high temperature stability under extreme conditions, but its resistance to cracking remains to be further studied. Longitudinal cracks caused by transverse tensile stress are the main reasons causing cracking of pavement. Therefore, the maximum horizontal tensile stress should be taken as an important control index for pavement design.