冷拌环氧浇注式沥青混合料性能评价

Development of Cold Mix Epoxy Poured Asphalt Materials

为了解决钢桥面铺装层病害高效修复养护技术问题,结合环氧沥青混合料的材料特点与浇注式沥青混合料的工艺特点,开发新型钢桥面铺装养护材料——冷拌环氧浇注式沥青混合料,并进行了胶结料拉伸断裂试验及混合料流动性、稳定度、抗压强度和弯拉强度试验,对比分析确定胶结料配方。同时与钢桥面典型铺装材料进行了高温稳定性、抗裂性、温缩性及抗疲劳等路用性能对比分析,对其综合性能进行评价。结果表明:环氧沥青力学性能优良,拉伸强度为14.21 MPa,断裂延伸率为45%,混合料抗压强度随温度升高线性下降,70℃马歇尔稳定度超100 kN,25℃立方体抗压强度为42.9 MPa, 70℃动稳定度远超10 000次/mm;混合料-10℃极限弯曲应变为3 241με,劈裂强度大,水稳性优异,冻融劈裂强度比及浸水残留立方体抗压强度均在95%以上;混合料温缩系数介于环氧沥青混合料和浇注式沥青混合料之间,具备较好的协同变形能力,温度收缩系数在50℃~-30℃范围内近似呈线性规律下降;混合料疲劳性能指标冲击韧性为1 052 N·mm,与浇注式沥青混合料、高弹改性SMA接近,疲劳性能优良。

In order to meet the efficient repair and maintenance of steel bridge deck pavement defects from the perspective of technical requirement,combined with material characteristics of epoxy asphalt mixture and process characteristics of cast asphalt mixture,a new type steel bridge deck pavement maintenance materials,the cold mix epoxy cast asphalt mixture,is developed,and tensile fracture test and mixture fluidity,stability,compressive strength and bending tensile strength test are carried out for the binder,comparative analysis is conducted to determine the binder composition.At the same time,the pavement properties of steel bridge deck,such as high temperature stability,crack resistance,temperature shrinkage and fatigue resistance,are compared and analyzed,and its comprehensive performance is evaluated.The results show that the epoxy asphalt has excellent mechanical properties,the tensile strength is 14.21 MPa,the fracture elongation is 45%,the compressive strength of the mixture decreases linearly with the increase of temperature,the Marshall stability at 70℃exceeds 100 kN,the cubic compressive strength at 25℃is 42.9 MPa,and the dynamic stability at 70℃exceeds 10000 times/mm.The ultimate bending strain of the mixture at-10℃is 324lμe,the splitting strength is large,the water stability is excellent,the freeze-thaw splitting strength ratio and the compressive strength of the submerged residual cube are above 95%.The temperature shrinkage coefficient of the mixture is between the epoxy asphalt mixture and the cast asphalt mixture,and has a good synergistic deformation capability,and the temperature shrinkage coefficient approximately decreases linearly within 50℃~-30℃.The impact toughness of the mixture is 1052 N·mm,which is close to that of cast asphalt mixture and high elastic modified SMA,and has excellent fatigue properties.