玄武岩纤维对聚氨酯改性沥青混合料水稳定性提升研究

Study on the improvement of water stability of polyurethane-modified asphalt mixture by basalt fiber

为解决聚氨酯改性沥青混合料水稳定性不良的缺陷,通过浸水马歇尔试验、冻融循环条件下的劈裂试验、低温弯曲试验,研究不同玄武岩纤维掺量下聚氨酯改性沥青混合料的抗水损害能力。结果表明:在冻融循环作用下,玄武岩纤维降低了沥青混合料水损作用造成的空隙率变化,增强了沥青间的粘附性,当纤维掺量为0.3%时,其提升作用最强,残留稳定度和劈裂强度比分别提升了10.9%、32.3%,有效降低了冻融循环引起的弯拉强度与弯拉应变的下降速率,增强沥青混合料之间的粘结力,聚氨酯沥青混合料的水稳定性能得到提高。

In order to solve the defect of poor water stability of polyurethane-modified asphalt mixture,this paper studied the water damage resistance of polyurethane-modified asphalt mixture under different basalt fiber content through immersion Marshall test,splitting test under freeze-thaw cycle condition and low-temperature bending test.The results showed that under the action of freeze-thaw cycle,basalt fiber reduced the change of porosity caused by water damage of asphalt mixture and enhanced the adhesion between asphalt.When the fiber content was 0.3%,the improvement effect was the strongest,and the residual stability and splitting strength ratio were increased by 10.9%and 32.3%,respectively.It effectively reduced the decline rate of flexural tensile strength and flexural tensile strain caused by freeze-thaw cycles,enhanced the bonding force between asphalt mixtures,and improved the water stability of polyurethane-modified asphalt mixtures.