橡胶粉对水泥稳定级配碎石力学性能与变形特性的影响

Effect of Rubber Powder on Mechanical Properties and Deformation Characteristics of Cement Stabilized Gradation Crushed Stone

为了增强水泥稳定碎石的柔韧性、抗裂缝性能与抗疲劳耐久性能,将0~4.75 mm小汽车轮胎胶粉等质量替代集料,基于室内试验研究了橡胶粉掺量对橡胶粉-水泥稳定级配碎石混合料力学性能和变形特性的影响规律.结果表明:掺加橡胶粉降低了水泥稳定级配碎石的力学性能和抗温缩特性,在常规4.5%~5.5%水泥剂量范围内,2%~4%橡胶粉水泥稳定碎石力学性能和抗冲刷性能满足规范要求,橡胶粉-水泥稳定碎石可作为路面结构的变形协调功能层.掺加橡胶粉提高了水泥稳定级配碎石混合料的劈裂破坏应变与弯拉破坏应变与抗疲劳耐久性能,但是掺加橡胶粉能降低水泥稳定级配碎石混合料温缩性能的不利影响,推荐适宜的橡胶粉掺量为3%.实体工程跟踪检测结果表明,橡胶粉等质量替代3%细集料后提高了水泥稳定级配碎石混合料的抗裂性能.

In order to enhance the flexibility,crack resistance and fatigue durability of cement stabilized macadam,the mass of 0~4.75mm car tire rubber powder was used instead of aggregate.Based on the laboratory test,the influence of rubber powder content on the mechanical properties and deformation characteristics of rubber powder-cement stabilized macadam mixture was studied.The results show that adding rubber powder reduces the mechanical properties and temperature shrinkage resistance of cement stabilized graded macadam.In the conventional dosage range of 4.5%~5.5%cement,the mechanical properties and anti-scour performance of 2%~4%rubber powder cement stabilized macadam meet the specification requirements.Rubber powder-cement stabilized macadam can be used as the deformation coordination function layer of pavement structure.Adding rubber powder can improve the splitting failure strain,bending and tensile failure strain and fatigue durability of cement stabilized graded macadam mixture.However,adding rubber powder can reduce the adverse effect of temperature shrinkage performance of cement stabilized graded macadam mixture,and it is recommended that the appropriate amount of rubber powder be 3%.The engineering tracking test results show that the crack resistance of cement stabilized graded crushed stone mixture is improved after the equal mass of rubber powder replaces 3%fine aggregate.