【作者】 廖卫东；

【导师】 陈文； 吴少鹏；

【作者基本信息】 武汉理工大学 ， 材料学， 2007， 博士

【摘要】 在如何控制旧水泥混凝土路面加铺沥青面层后反射裂缝的问题上，道路工程界的研究者和实践者围绕反射裂缝产生的力学机理和延缓反射裂缝的措施——在沥青加铺层结构、材料及加铺层设计方法、试验方法等各个方面都作了大量的理论分析和试验评价。目前对基于应力吸收层的沥青加铺层结构和材料的研究还不够全面、深入。本文在前人研究的基础上，继续对沥青加铺层反射裂缝产生机理、加铺层设计方法以及基于应力吸收层的沥青加铺层结构及材料等作进一步深入研究和加铺层新材料的研发。本文主要进行了以下六个方面的研究工作：第一方面研究工作是从理论上探讨应力吸收层沥青混合料能减小沥青加铺层产生应力集中的机理。依据沥青路面线弹性断裂力学基本理论与有限元方法对应力吸收层反射裂缝的成因及扩展机理进行分析，研究了沥青加铺层厚度、应力吸收层模量、初始裂纹长度和降温幅度及轴载等参数变化对应力吸收层裂缝应力强度因子的影响程度，通过力学分析揭示了旧水泥混凝土路面接缝和裂缝处应力吸收层能减小加铺层产生应力集中的原因。第二方面研究工作是通过对应力吸收层的试验室评价，定性研究应力吸收层加铺结构的防裂、抗车辙能力，以及通过试验确定设计参数。在室内理想条件下采用大型疲劳试验仪及MTS进行不同加铺层结构疲劳破坏的对比试验，通过模拟基于应力吸收层的沥青加铺层荷载型及温度型反射裂缝的产生、扩展过程，来评价不同结构沥青加铺层特别是应力吸收层结构抵抗反射裂缝的能力，并以此验证了理论计算结果，表明应力吸收层是一种很好的延缓反射裂缝的新材料。第三方面研究工作是对应力吸收层结构进行力学分析。定量研究设计参数的变化对应力吸收层加铺结构的影响。对试验路和实体工程采用的应力吸收层新型加铺层结构及其它几种典型加铺层结构的防裂机理进行了分析，以及车辆荷载和温度荷载对比力学计算，说明在荷载作用下应力吸收层对减少车辆荷载应力和温度荷载应力效果十分明显。第四方面研究工作是研究基于应力吸收层的沥青加铺层设计方法。在室内试验结果、结合理论分析及对试验路、沥青加铺层实体工程施工控制、使用状况的跟踪观测的基础上，提出了基于应力吸收层的沥青加铺结构的弯沉-交通量设计方法，以及设计双控指标和满足设计年限内交通量要求的加铺层最小厚度。即加铺前混凝土板板角接缝和裂缝处单点弯沉≤0.14mm、板角接裂缝两侧相邻板的弯沉差≤0.06mm。满足交通量要求的应力吸收层之上的加铺层最小厚度为≥8cm。采用本文提出的设计方法在武黄、汉宜高速公路共计350公里的旧水泥混凝土路面上加铺沥青层的应用表明防止反射裂缝效果良好。第五方面研究工作是通过对应力吸收层沥青及混合料路用性能的分析，得出了应力吸收层特种改性沥青结合料的路用性能特点和其在应力吸收层中的作用效果与使用的合理性，以及应力吸收层混合料合理的矿料级配范围和具有优异的低温抗变形能力及抗疲劳性能。进而为确定应力吸收层混合料设计提供了理论依据。第六方面研究工作是在上述研究成果的基础上，研发了SamPave应力吸收层新材料。并通过研发的新型应力吸收层沥青结合料，结合提出的矿料级配，采用SGC成型方法，配制了SamPave应力吸收层混合料，铺筑了试验路。更多还原

【Abstract】 The researchers and practitioners of civil engineer have made massive theoretical analysis and testing appraises about the aspects including the mechanics how the reflected cracking and the delayed reflected crack were produced and expanded and the structure, material, design and the testing method of the overlay of asphalt concrete. At present the research is not enough comprehensive and thorough to the structure and design of the overlay of stress absorption interlayer. The paper made the further thoroughly studies about the new material of the overlay to the above. The paper has mainly carried on six aspects as follows:The first aspect is that the reason why stress absorption interlayer can decrease the stress concentration in theory is discussed. The fact that these parametric variation including the thickness of asphalt overlay, the modulus of stress absorption interlayer, the length of the initiate cracking, the cooling amplitude and axle load so on, has an effect on the stress intensity factor of stress absorption interlayer is analyzed. All these are based on the theory of the linear elastic fracture mechanics and the finite-element method by which the reason and expanding mechanics of stress absorption interlayer are analyzed. It is opened out that the stress concentration is decreased by the joint of the old cement concrete pavement and stress absorption interlayer in the joint through the mechanical analysis.The second aspect is to qualitatively study the crack control and the resisting tracking force of the overlay then determine the design parameter from the test room of stress absorption interlayer. The contrast test to the endurance failure of different overlay has been made by large fatigue machine and MTS in indoor ideal conditions. To evaluate the resisted reflecting crack of different asphalt overlay, especially the one of stress absorption interlayer, and validate the academic result. This article simulated some courses how the load and temperature reflecting crack based on the asphalt overlay had been produced and expanded. All these indicated that stress absorption interlayer is a good kind of material which can delay the expansion of the reflecting crack. The third aspect is to make some mechanical analysis to the stress’s absorption interlayer then study the influence of stress absorption interlayer quantificationally as the variety of the design parameter. Some jobs were completed. The crack control mechanics of new-style overlay and other typical overlay to trial pavement and solid project was analyzed. And the vehicular load was compared to temperature load by mechanical calculation. Finally it is proved that stress absorption interlayer can decrease the vehicular load stress and temperature stress effectively under load.The fourth aspect is to discuss the design method of the asphalt overlay based on the stress’s absorption interlayer. Some things are given including the control and design method of deflection based on stress absorption interlayer, the design of double control index and the minimal thickness which can meet the traffic. All these were completed on the basis of actual construction control and the observation result of working condition which were given by the trial pavement and solid project, the indoor tests and the calculated analysis. It means that the single-point’s deflection should be less and equal than 0.14mm, and the deflection of bilateral plate edges should be less and equal than 0.06mm at the joint and crack of the coruer plate before overlay. The minimal thickness of overlay above stress absorption interlayer which can meet the traffic is 8cm.The fifth aspect is that the pavement performance of the special modifying asphalt binder with stress absorption interlayer and its effect and rationality are given, and which provided some bases to how to confirm the design parameter of the mixture of stress absorption interlayer. All these are completed by the research of the asphalt of stress absorption interlayer and the pavement of mixture.The sixth aspect is to exploit the new material of SamPave stress absorption interlayer on the basis of the above independently. The mixture of Sam Pave stress absorption interlayer is made up combined to the given material’s gradation, and then builds the trial pavement.更多还原