测力延度试验评价沥青低温性能的指标研究

Study on the Index of Force Ductility Test to Evaluate the Low Temperature Performance of Asphalt

研究针对测力延度试验评价SBS沥青低温性能的适用性问题,在测力延度试验低温条件下对SBS沥青进行拉伸加载,探讨了四种SBS沥青的荷载位移曲线变化规律。通过对SBS沥青的荷载位移曲线后处理得到黏韧性指标,并与低温弯曲梁流变试验结果进行对比分析来验证黏韧性指标评价低温性能的合理性。研究结果表明,沥青第二峰值力F_(2max)、黏弹性指标Sv和黏韧性指标R_(V/T)均与低温弯曲梁流变试验-18℃条件下所测得劲度模量S保持较强的相关性(R^(2)=0.96852,R^(2)=0.92110和R^(2)=0.96963),可作为SBS沥青低温性能的评价指标。

In this paper,the applicability of the low-temperature performance of SBS asphalt in the force ductility test was studied,and the load displacement curve variation law of four SBS asphalt was discussed by tensile loading under the low temperature conditions of the force ductility test.The viscosity indicators was obtained by posttreating the load displacement curve of SBS asphalt,and the rheological test results of low temperature bending beam rheometer test were compared and analyzed to verify the rationality of the viscous toughness index to evaluate the low-temperature performance.The results showed that the second peak force of asphalt F_(2max),viscoelasticity index S_(v),and viscosity index R_(V/T ) maintain a strong corelation with the strength modulus S measured under the low temperature bending beam rheological test at-18℃(R^(2)=0.96852,R^(2)=0.92110 and R^(2)=0.96963),which can be used as the evaluation index of low temperature performance of SBS asphalt.