PP纤维水稳碎石抗弯韧性及疲劳性能试验研究  

Experimental Study on Flexural Toughness and Fatigue Property of Polypropylene(PP) Fiber Reinforced Cement-stabilized Macadam

作　　者：马银华[1] 易志坚[1] 杨庆国[1] 

机构地区：[1]重庆交通大学土木建筑学院,重庆400074

出　　处：《重庆建筑大学学报》2008年第1期58-62,共5页Journal of Chongqing Jianzhu University

基　　金：内蒙古交通科技项目资助(NJ-2005-23)

摘　　要：通过四点弯曲试验和疲劳试验，对聚丙烯（PP）纤维水泥稳定碎石和普通水泥稳定碎石半刚性基层材料的弯曲韧性及疲劳性能进行了研究。试验得到两种材料的荷载-挠度曲线，按照JCI和ASTMC1018-97标准方法，计算得到两种材料的韧性指数；试验还得到材料在不同应力水平下的疲劳寿命，并回归出疲劳方程。研究结果表明，与普通水泥稳定碎石相比，体积掺量仅为0．077％的PP纤维水泥稳定碎石的抗折强度提高约10％，极限变形提高150％，JCI韧性指数提高67．7％，ASTMC1018-97韧性指数提高36．1％～79．8％，疲劳寿命提高126％～352％，增强效果十分显著。同时，基于断裂力学原理，揭示了纤维的阻裂增韧和抗疲劳机理。By four-point bending test and fatigue test, the authors studied the flexural toughness and fatigue property of semi-rigid base course of cement-stabilized macadam with and without polypropylene（PP） fiber. Some significant data about these two kinds of material have been obtained, such as the load-deflection curves, toughness index according to the standard methods of JCI and ASTM C1018-97, the fatigue lifetime under different stress levels and the fatigue lifetime regression equation. The results show that the reinforcing effect of the PP fiber is remarkable; the bending strength, ultimate deformability, JCI toughness index, ASTM C1018-97 toughness index and fatigue life of cement-stabilized macadam with PP fiber are increased by about 10%, 150%, 67.7%, 36.1%-79.8%, and 126%-352%, respectively, when the volume fraction of PP fiber is only 0. 077%. At the same time, the authors revealed the toughness improving mechanism and the antifatigue mechanism of the fiber in such material based on the fracture mechanics theory.

关 键 词：聚丙烯纤维 水泥稳定碎石 半刚性基层 弯曲韧性 疲劳性能 断裂力学 阻裂增韧机理 抗疲劳机理 

分 类 号：U416.214[交通运输工程—道路与铁道工程] TU502.6[建筑科学—建筑技术科学]