玄武岩纤维对钢渣沥青混合料性能影响研究

Effect of Basalt Fiber on Performance of Steel Slag-Asphalt Mixture

为改善钢渣沥青混合料(SAM)抗裂性能,并尽可能降低钢渣(SS)膨胀特性对混合料耐久性的影响,基于车辙试验、SPT动态模量试验、低温弯曲试验、冻融劈裂试验、弯曲疲劳试验、SEM试验等,对不同掺量玄武岩纤维(BF)对SAM高、低温性能和水稳定及疲劳性能的影响及增强机理进行研究。结果表明:BF可显著增强SAM高温抗变形能力,且对不同SS掺量SAM低温柔韧性均有一定的提高;随着冻融循环次数增加,玄武岩纤维-钢渣沥青混合料(BF-SAM)的水稳定性降低幅度较SAM明显减小;BF的加筋、阻裂作用提高了SAM的疲劳寿命。综合各项路用性能,BF-SAM的推荐掺量为0.4%(质量分数)的BF,45%~55%(质量分数)的SS。

To improve the anti-cracking property of steel slag-asphalt mixture(SAM),and minimize the effect of steel slag(SS)expansion characteristics on the durability of asphalt mixture,the comparative research on the effects and reinforcement mechanism of different contents of basalt fiber(BF)on the high and low temperature performance,water stability and fatigue property of SAM was implemented via rutting test,SPT dynamic modulus test,low temperature bending test,freeze-thaw splitting test,bending fatigue test,SEM test,etc.Results show that the addition of BF improves the high temperature anti-deformability,and increases the low temperature flexibility of SAM with different SS content to a certain extent.With the increase of freeze-thaw cycles,the decrease of water stability of BF-SAM is significantly lower than that of ordinary SAM.The reinforcement and crack resistance of BF improve the fatigue life of SAM.After comprehensive consideration of various road performance,the recommended BF content of BF-SAM is 4%(mass fraction)and the recommended SS content range is 45%to 55%(mass fraction).