桥面沥青铺装鼓泡形成扩散机理与试验评价方法研究

Blister is one of the main damage forms on bridge deck asphalt pavements. There are some limitations for analytical solution to reveal the mechanism of blister propagation on bridge deck pavement absolutely. This research focuses on the occuring of blister on asphalt pavements of steel bridge decks or concrete bridge decks. Based on the field investigation and core sample test analysis, the causes, failure modes, characteristics and regularities of distribution are studied systematically with mathematical statistics method, which can provide a theoretical basis for the development of a blister test device. By developing a device for simulation and analysis of the blister, the influences of different factors, such as deck pavement structure, material properties, situation of the bridge deck pavement, on the propagation and deformation characteristics of blister are manifested. Based on that, a reasonable viscoelastroplasticity constitutive in extreme fatigue mode are established, with which to accomplish the numerical analysis of the blister propagation in two modes. By comparing with the mechanical experiments, the formation and propagation mechanisms of blister is revealed. New evaluation indexes and method for blisters of bridge deck are proposed by using interface fracture energy theory. And measures to prevent the development of blister on asphalt pavements of bridge decks are suggested in accordance with the formation and propagation mechanisms and characteristics.

鼓泡是桥面沥青铺装的主要破坏形态之一，目前广泛采用的经典力学解析解不能完全揭示桥面铺装鼓泡扩散机理，存在一定的局限性。本项目以钢桥面和混凝土桥面沥青铺装鼓泡为研究对象，通过对鼓泡病害的现场调查及芯样测试分析，应用数理统计方法，系统研究其成因、破坏形式、特点以及分布规律，为开发鼓泡试验装置提供理论依据；开发鼓泡模拟和力学分析试验装置，分析桥面铺装结构、材料特性、桥面状况等不同因素对桥面铺装鼓泡的影响规律，揭示其扩散与变形特征；在此基础上，合理构建铺装层在极限、疲劳模式下的粘弹塑性本构关系，完成两种模式下鼓泡扩散规律的数值分析，并与力学实验结果对比验证后，揭示桥面铺装鼓泡形成与扩散机理；应用界面断裂力学理论基于能量角度提出桥面铺装鼓泡病害的评价指标和试验评价方法；根据鼓泡病害形成扩散机理与破坏特点，针对桥面铺装设计、施工、养护等阶段提出防治鼓泡病害的具体措施。

鼓泡是桥面沥青铺装的主要破坏形态之一，目前广泛采用的经典力学解析解不能完全揭示桥面铺装鼓泡扩散机理，存在一定的局限性。本项目以钢桥面和混凝土桥面沥青铺装鼓泡为研究对象，通过对鼓泡病害的现场调查和自行开发的室内自然模拟和加压模拟装置，系统研究了其成因、破坏形式、特点；揭示了桥面铺装结构、材料特性、桥面状况等不同因素对桥面铺装鼓泡的影响规律，以及鼓泡扩散与变形机制。在此基础上，基于界面断裂力学基本原理，建立了含有鼓泡的桥面铺装结构计算模型，推导了铺装层鼓泡尖端能量释放率的解析表达式，提出了基于相位角和断裂韧度的鼓泡断裂准则，采用数字图像相关技术和虚拟裂纹闭合技术对鼓泡扩展过程进行试验研究及数值模拟以及气体压力作用下混凝土桥面铺装层鼓泡扩展行为；基于能量角度提出桥面铺装鼓泡病害的评价指标和试验评价方法；研究成果为桥面铺装设计、施工、养护等阶段提出防治鼓泡病害的具体措施提供了理论基础。