水稳碎石材料细观修复行为及最佳修复时机  

Research on the mesoscopic healing behavior and optimal healing occasion of cement-stabilized macadam

作　　者：赵晓康 董侨[2] 董是 陈雪琴 ZHAO Xiaokang;DONG Qiao;DONG Shi;CHEN Xueqin(School of Highway,Chang′an University,Xi′an 710064,China;School of Transportation,Southeast University,Nanjing 211189,China;College of Transportation Engineering,Chang′an University,Xi′an 710064,China;College of Science,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]长安大学公路学院,西安710064 [2]东南大学交通学院,南京211189 [3]长安大学运输工程学院,西安710064 [4]南京理工大学理学院,南京210094

出　　处：《哈尔滨工业大学学报》2024年第3期78-88,共11页Journal of Harbin Institute of Technology

基　　金：长安大学中央高校基本科研业务费专项资金(300102213102);国家自然科学基金(51978163);陕西省博士后科研项目(2023BSHYDZZ121)。

摘　　要：为了探究水稳碎石(CSM)材料的细观修复行为及最佳修复时机,基于损伤-愈合模型对其修复效果影响因素进行了分析。首先,基于离散元法(DEM)建立CSM的二维半圆弯曲(SCB)数值试件,引入损伤因子模拟材料的局部损伤与愈合效应,进而构建细观尺度的损伤-愈合数值模型。其次,通过虚拟SCB疲劳试验实现不同程度的荷载损伤,基于愈合变量来表征损伤修复过程,模拟局部损伤愈合行为。然后,基于损伤-愈合模型开展不同损伤状态下的修复效果评估,分析初始损伤状态、愈合程度对修复效果的影响规律,并进一步研究了CSM材料的最佳修复时机。结果表明:所提出的损伤-愈合模型能够再现CSM材料在细观尺度上的损伤与愈合行为,初始损伤状态和愈合程度对修复效果的影响具有非线性,在70%~85%的疲劳寿命阶段,局部损伤修复对结构强度的提升作用较为显著。基于对损伤修复效果的数值分析,推荐将70%~85%的疲劳寿命作为CSM材料的最佳修复时机,此外,选择强度优良、数量充足的愈合剂可以最大程度地提升局部损伤修复效果。To investigate the healing behavior and healing occasion of cement stabilized macadam(CSM),the factors influencing the healing effect were analyzed based on the damage-healing model.Firstly,a 2D semicircular bending(SCB)numerical specimen of CSM was established through the Discrete Element Method(DEM).The damage factor was adopted to simulate the local damage and healing effect,and then the mesoscopic damage-healing model was constructed under a SCB loading mode.Secondly,the virtual SCB fatigue test was adopted to realize different degrees of load damage.The healing variable was established to simulate the healing behavior of local damage.Lastly,based on the damage-healing model,the healing effects were evaluated to reveal the influence of the initial damage state and healing degree of specimens.The optimal healing occasion of CSM was further studied.The results show that the proposed numerical damage-healing model can explain and simulate the mesoscale damage and healing behavior of CSM materials.The initial damage state and healing degree have nonlinear effects on healing effect.In the fatigue life stage of 70%-85%,local damage healing has a significant effect on strength improvement.According to the healing results,70%-85%fatigue life is recommended as the optimal healing occasion for CSM materials.In addition,enough healing agent with moderate strength can help to maximize the healing effect of local damage.

关 键 词：道路工程 水稳碎石 损伤愈合 修复时机 离散元法 半圆弯曲 

分 类 号：U416.214[交通运输工程—道路与铁道工程]