抑制反射裂缝的装配式复合路面接缝性能研究

Joint performance of precast composite pavement and reflection crack suppression

针对荷载型反射裂缝导致装配式复合路面使用寿命缩短的问题,基于弹性地基梁理论和疲劳损伤分析,推导了荷载作用下装配式复合路面接缝处沥青加铺层剪切应力和层底弯拉应力的计算方法,并分别构建了接缝处相邻板弯沉差和接缝宽度与荷载型反射裂缝扩展寿命的关系。研究结果表明:不同交通荷载等级下,通过合理设置相邻板弯沉差和接缝宽度可有效控制沥青层寿命;裂缝扩展寿命随接缝宽度和相邻板弯沉差增大而缩短,随沥青加铺层厚度增加而延长;给出了不同交通荷载等级下的初始相邻板弯沉差和接缝宽度的大小,并建议装配式复合路面沥青层厚度应不低于0.1 m。研究成果可为装配式复合路面的进一步推广应用提供理论基础。

To prolong the service life of precast composite pavement,fatigue damage analysis and beam on elastic foundation theory are used for analyzing load-type reflection crack.Then,the relationship between adjacent plate deflection difference,joint width and the propagation life of load-type reflection crack is established by deriving the shear stress and bottom layer tensile stress of the asphalt overlay at the joints of precast composite pavement.The results show that the asphalt layer life can be effectively controlled through two factors:adjacent plate deflection difference and joint width.The crack extension life is shortened by increasing joint width and adjacent plate deflection difference and is extended by increasing asphalt pavement thickness.Finally,the initial value of plate deflection difference and joint width in different traffic load levels are delineated,the thickness of the asphalt layer should be greater than 0.1 m.In conclusion,this study establishes the grounds for the further application of precast composite pavement.