基于弯曲应变能的纤维沥青混凝土抗裂性能评价方法

沥青混合料常采用低温小梁弯曲试验来评价其低温抗裂性,其中抗弯拉强度、弯拉应变和弯曲劲度模量被用作表征沥青混合料低温性能的重要指标。通过室内试验揭示,以上三个指标并不能单独准确地反映沥青混合料的低温抗裂性能。借用弯曲应变能密度临界值这一概念,采用能量法对不同掺量下的纤维沥青混合料的低温抗裂性能进行重新分析、评价,能较好地反映纤维沥青混凝土的抗裂性能,同时也对这一指标进行了验证分析。研究结论认为,采用弯曲应变能密度临界值作为纤维沥青混凝土的低温抗裂性能评价指标是合理、可行的。

Evaluation Methodof Anti-Cracking Performance for Fiber Asphalt Concrete Based on Critical Flexural Strain Energy

Beam bending test is often used to evaluate the low temperature anti-cracking performance of asphalt mixture,and flexural strength, flexural strain and flexural modulus can be used as evaluation parameter.Laboratory testing shows that all of the three evaluation parameters can’t exactly reflect the low temperature anti-cracking performance of asphalt mixture individually.Based on the definition of critical flexural strain energy,it was used as an evaluation parameter to analyze and evaluate anti-cracking performance of fiber asphalt mixture at different doses of fiber.The result shows that critical flexural strain energy parameter is reasonable and feasible.