摘要
为了研究高比例RAP对厂拌热再生沥青混合料低温性能的影响,选择AC-20和ATB-25两种沥青混合料,RAP掺量均设置为35%、40%、45%,均添加9%旧沥青用量的再生剂(CL),通过小梁弯曲试验和半圆弯曲试验(SCB)对两种类型沥青混合料的低温性能进行试验研究。研究结果表明:对于低温小梁弯曲试验,随着RAP掺量的增加,AC-20型和ATB-25型再生沥青混合料的抗弯拉强度、弯曲劲度模量均随着RAP掺量的增加而增加,最大弯拉应变均随着RAP掺量的增加逐渐减小。当RAP掺量超过35%时,混合料低温性能不满足规范要求。对于低温半圆弯曲试验,随着RAP掺量增加,AC-20和ATB-25再生沥青混合料半圆弯曲试验对应的断裂能和断裂韧性降低,断裂刚度增大。在同一RAP掺量下,AC-20沥青混合料相比ATB-25沥青混合料的低温性能随RAP掺量的变化更敏感。随着再生剂掺量的增加,AC-20沥青混合料对于小梁弯曲和半圆弯曲试验,其低温性能均有所改善。
In order to study the influence of a high proportion of RAP on the low-temperature performance of plant-mixed hot recycled asphalt mixtures,two asphalt mixtures,AC-20 and ATB-25,were selected.The RAP dosages were set at 35%,40%,and 45%respectively,and 9%of the amount of recycled asphalt(CL)was added to both.The low-temperature performance of two types of asphalt mixtures was experimentally studied through small beam bending tests and semicircular bending tests(SCB).The research results show that for the low-temperature trabecular bending test,with the increase of RAP content,the flexural tensile strength and bending stiffness modulus of AC-20 type and ATB-25 type recycled asphalt mixtures increase with the increase of RAP content,and the maximum flexural tensile strain gradually decreases with the increase of RAP content.When the RAP content exceeds 35%,the low-temperature performance of the mixture does not meet the specification requirements.For the low-temperature semi-circular bending test,with the increase of RAP content,the corresponding fracture energy and fracture toughness of the semi-circular bending test of AC-20 and ATB-25 recycled asphalt mixtures decrease,while the fracture stiffness increases.Under the same RAP content,the low-temperature performance of AC-20 asphalt mixture is more sensitive to the change of RAP content compared with ATB-25 asphalt mixture.With the increase of the dosage of regenerant,the low-temperature performance of AC-20 asphalt mixture in the beam bending and semi-circular bending tests has been improved.
作者
曹青霞
刘大海
李自齐
王学娟
CAO Qingxia;LIU Dahai;LI Ziqi;WANG Xuejuan(Gansu Provincial Communications Planning Survey and Design Institute Co.,Ltd.,Lanzhou 730030;Gansu Changlong Highway Maintenance Technology Institute Co.,Ltd.,Lanzhou 730030)
出处
《中国建材科技》
2025年第4期101-106,112,共7页
China Building Materials Science & Technology
基金
甘肃省交通运输厅科技项目(编号:2024-07,2024-28)
甘肃省陇原青年英才项目(编号:2024-01)。
关键词
道路工程
沥青混合料
再生
沥青路面回收料
低温性能
road engineering
asphalt mixture
regeneration
recycled asphalt pavement materials
low temperature performance
