摘要
为研究PET聚酯纤维、SBS及橡胶粉对沥青混合料断裂行为的影响,采用半圆弯曲(SCB)试验,结合Ⅰ型、Ⅰ/Ⅱ型混合2种断裂模式,通过峰值荷载、断裂能、极限位移、抗裂指数、柔性指数、断裂拐点等多指标系统分析3类改性材料的作用机制。结果表明:1)PET聚酯纤维通过形成三维网络发挥宏观裂缝桥接与抵抗作用,显著提升混合料峰值荷载、断裂能,增强抗断裂性能,且对峰后断裂能提升作用更突出;2)SBS与橡胶粉通过强化沥青黏韧性提升混合料柔性指数与极限位移,增强柔韧性,且对断裂拐点调控更显著,可有效阻碍峰前微裂纹形成与整合。研究提出“聚合物改性+PET聚酯纤维掺加”复合方案,可协同强化混合料峰前抗微裂纹能力与峰后宏观裂缝扩展抑制效果,全面提升抗裂性能。
To study the influence of PET polyester fiber,SBS,and rubber powder on the fracture behavior of asphalt mixtures,a Semi-Circular Bending(SCB)test was conducted.Combined with two fracture modes(ModeⅠand mixed ModeⅠ/Ⅱ),the action mechanisms of the three types of modified materials were systematically analyzed through multiple indicators such as peak load,fracture energy,ultimate displacement,crack resistance index,flexibility index,and fracture turning point(DTP).The results indicate that:1)PET polyester fiber exerts macroscopic crack bridging and resistance effects by forming a three-dimensional network,significantly improving the peak load,fracture energy,and fracture resistance of the mixture,with a more prominent effect on increasing the post-peak fracture energy;2)SBS and rubber powder enhance the flexibility index and ultimate displacement of the mixture by improving the viscosity and toughness of asphalt,thereby increasing the flexibility.Moreover,they have a more significant regulatory effect on the fracture turning point and can effectively inhibit the formation and integration of micro-cracks in the pre-peak stage.This study proposes a composite scheme of"polymer modification+PET polyester fiber addition",which can synergistically enhance the pre-peak micro-crack resistance and post-peak macro-crack propagation inhibition effect of the mixture,achieving a comprehensive improvement in crack resistance.
作者
卜胤
余荣斌
赵华
BU Yin;YU Rongbin;ZHAO Hua(Jiangxi Province Tianchi Highway Technology Development Co.,Ltd.,Nanchang330036;School of Infrastructure Engineering,Nanchang University,Nanchang 330031)
出处
《公路交通技术》
2026年第1期10-16,共7页
Technology of Highway and Transport
基金
江西省自然科学基金资助项目(20232BAB204069)。
