沥青路面玻璃纤维橡胶沥青碎石封层的层间黏结性能

Interlayer Bonding Performance of Asphalt Pavement Glass Fiber Rubber Modified Asphalt Crushed Stone Sealing

反射裂缝和水损坏是半刚性基层沥青路面常见的病害形式。采用合适的封层可以延缓反射裂缝,起到防水作用,可有效提高道路服役寿命,为长寿命沥青路面奠定基础。采用70#基质沥青、橡胶沥青、不同粒径的碎石,以不同撒布量及不同预拌方法,针对上-中面层、中-下面层开展不同层间试件的直剪试验,对多达60种玻璃纤维橡胶沥青碎石封层方案进行层间黏结性能研究。结果表明:玻璃纤维橡胶沥青碎石封层作为应力吸收层可以发挥很好的防水、层间黏结作用,铺设于中面层与下面层层间也能获得较好的层间黏结性能;碎石粒径、碎石与沥青用量、预拌方法可影响沥青路面层间黏结性能,且不同层位需要选择合理的碎石粒径以保证层间粒径的连续性;特殊施工环境将降低层间黏结性能,碎石封层撒布完成后应尽快铺设上面层,同时尽量避免路面潮湿条件下施工;采用橡胶沥青预拌碎石可以增强橡胶沥青与碎石颗粒的黏结,预拌碎石常温撒布能显著提高层间黏结性能,施工和易性好,质量易于控制。研究成果为玻璃纤维橡胶沥青碎石封层的工程化应用提供一定试验基础。

Reflection crack and water damage are common diseases of asphalt pavement with semi-rigid base.Adopting suitable sealing layer can delay reflection crack,play waterproof role and effectively improve the service life of road,and lay the foundation for the long-life asphalt pavement.The different interlayer specimens are carried out by direct shear tests for upper-middle layer and middle-lower layer by using asphalt No.70,rubber asphalt and crushed stone with different particle sizes,with different spreading amount and different pre-mixing methods,the interlayer bonding properties of up to 60 kinds of glass fiber rubber asphalt macadam sealing schemes are studied.The result shows that(1)as a stress absorbing layer,the glass fiber rubber asphalt macadam seal can play a very good waterproof and interlayer bonding role;(2)the particle size of crushed stone,the amount of crushed stone and asphalt and pre-mixed method can affect the bonding performance of asphalt pavement;(3)special construction environment will reduce the bond performance between the layers,and the upper layer should be laid as soon as possible after the spreading of the crushed stone seal layer;(4)the premixed crushed stone with rubber asphalt can strengthen the bond between the asphalt and the crushed stone particles,and the premixed crushed stone spread at normal temperature can improve the bond performance between the layers.The study results provide a certain test basis for the engineering application of glass fiber rubber asphalt macadam seal.