Preparation and properties of PVA fiber modified resin-based micro-surfacing
To further improve the toughness and road performance of micro-surface layers,polyvinyl alcohol(PVA)fiber-modified resin-based micro-surface layers(WEA-Ⅰ and WEA-Ⅱ)were prepared.The performance before and after PVA fiber modification,as well as the dispersion status of PVA fibers in micro-surface layer mixtures under different addition methods,were investigated.The surface modification of PVA fibers and the addition methods for dispersing fibers were explicitly defined,and the composition ratio of PVA fiber-modified resin-based micro-surface layers was optimized.Cohesion,BPN,texture depth,water resistance,wet wheel abrasion,rutting deformation,and strip tensile tests were conducted to explore the molding state,skid resistance,abrasion resistance,water damage resistance,rutting resistance,and tensile toughness of the two types of PVA fiber-modified resin-based micro-surface layers at different fiber contents.The optimal fiber content was determined,and a comparative evaluation of the road performance of PVA fiber-modified resin-based micro-surface layers and other existing micro-surface layers was conducted.The results show that the surface treatment of PVA fibers with amino silicone oil yields the best modification effect.Using the fiber pre-blending method with aggregates until dispersion,adding water for stirring,and then adding emulsified asphalt in two stages achieves the most uniform distribution of PVA fibers in the micro-surface layer mixture without agglomeration.With the increase of PVA fiber content,the abrasion resistance,water damage resistance,rutting resistance,and tensile toughness of both micro-surface layers initially increase and then decrease.Compared to micro-surface layers without PVA fibers,the improvement in abrasion resistance of PVA fiber-modified resin-based micro-surface layers reaches 75%,while rutting resistance and tensile toughness increase by 36%to 61%and 80%to 120%,respectively.Both types of PVA fiber-modified resin-based micro-surface layers demonstrate excellent waterproof and skid resistance.Considering the overall performance changes of micro-surface layers,the recommended optimal content(mass fraction,the same below)of PVA fibers is 0.1%of the weight of the micro-surface layer mixture.7 tabs,18 figs,35 refs.