高速公路沥青路面半刚性基层结构剩余寿命评价方法研究

Study on Residual Life Evaluation Method of Semi-rigid Base Structure of Expressway Asphalt Pavement

针对高速公路沥青路面半刚性基层结构剩余寿命一直缺少定量化评价方法的问题,结合大量高速公路养护设计项目经验及数据积累,提出从结构完整性及结构强度衰减度两方面综合评价半刚性基层结构剩余寿命的方法。结构完整性给出了3种计算方法,包括利用探地雷达无损检测数据直接计算、路面病害与取芯数据结合判断及通过路表面病害特征推算;结构强度衰减度给出了4种计算方法,包括现场实测模量直接计算、弯沉盆特征参数分析、材料参数对比及结构强度指数评价。由于以上各种方法技术适用性不同,提出采用定量评价及定性分析相结合的方式,计算半刚性基层剩余寿命指数。利用对全国代表性省份高速公路大中修周期的调研结果,将高速公路大中修周期分布规律转化为路面结构寿命衰变规律,并与结构完整性及结构模量衰减度两项评价指标建立匹配关系,从而实现了对现有路面结构剩余寿命的定量化计算。将以上成果进行总结提炼,建立了一套完整的理论分析模型及分析流程,并在实际工程中进行了验证,发现评价结果与路面结构实际破坏特点较为匹配,可用于指导半刚性基层沥青路面养护设计实践。

In view of the problem of lack of quantitative evaluation methods for the remaining life of semi-rigid base structure of expressway asphalt pavement,combining with the experiences and data accumulations of a large number of expressway maintenance design projects,a method for comprehensively evaluating the remaining life of semi-rigid base structure is proposed from the aspects of structural integrity and structural strength attenuation.Three calculation methods for structural integrity are presented,including direct calculation using GPR non-destructive testing data,combining judgment of pavement disease with coring data,and estimation by road surface disease characteristics.Four calculation methods for structural strength attenuation are given,including direct calculation using on-site measured modulus,analysis of characteristic parameters of deflection basin,comparison of material parameters,and evaluation of structural strength index.Due to the different applicability of the above methods and techniques,a method of combining quantitative evaluation and qualitative analysis is proposed to calculate the remaining life index of semi-rigid base.Using the survey results of major and medium repair cycles of expressways in representative provinces in China,the distribution rule of major and medium repair cycles of expressways is transformed into the rule of pavement structure life decay,which is matched with the evaluation indicators of structural integrity and structural modulus attenuation,so the quantitative calculation of the remaining life of current pavement structure is realized.After summarizing the above results,a complete set of theoretical analysis models and analysis procedures are established and verified in actual projects.It is found that the evaluation results match the actual damage characteristics of pavement structure,it can be used to guide the practice of maintenance design of semi-rigid base asphalt pavement.