【作者】 刘洪海；

【导师】 水中和；

【作者基本信息】 武汉理工大学 ， 材料学， 2008， 博士

【摘要】 当前我国高速公路建设呈跳跃式发展态势。但由于技术储备不足,加之车流量大,车辆超载严重等原因,导致在高速公路快速发展的同时,沥青路面的早期损坏问题同样十分突出。调查研究表明:产生沥青路面早期损坏的原因十分复杂,除了环境和荷载因素外,还与路面结构形式、混合料组成设计、施工技术等许多方面有关。尽管近些年来在沥青路面结构和混合料组成设计上进行了大量的研究,而且在室内试验研究中取得了良好的综合性能,但是许多实体工程路面早期损坏问题依然十分严重。特别是有些路面虽然直接采用了国外的先进设计理念,也没有得到满意的结果。愈来愈多的工程实践表明:在高速公路建设中混合料的施工特性、设备应具备的性能、设备之间的匹配关系、设备与材料之间的相互作用特性等对保证和提高路面质量具有重要的作用。本文针对以上问题进行了系统的理论与工程应用研究。沥青混合料因矿料级配不同构成了不同的组织结构,由混合料的结构状况、体积性能和施工特性共同决定了其使用性能。高性能混合料不同于传统混合料的级配与性能,其粗、细集料用量有严格的范围,粗一级集料形成的空隙决定了细一级集料的用量,形成多级嵌挤密实结构,使混合料既具有高抗车辙能力又有抗水损坏的综合性能。因此本文中首先分析研究了高性能混合料的级配特征、参数控制、体积特性和影响体积性能的因素、施工质量控制等方面的问题,提出了保证混合料优良性能的级配允许变化范围和施工参数控制范围。机械设备应针对具体的作业对象选择功能和确定参数,以适应千变万化的路面结构、材料组成及环境要求,发挥其最佳的工作特性。因此本文分析了沥青路面施工中的主要设备的结构原理、工作特性和影响设备性能的因素,提出了主要控制指标。深入研究了搅拌设备与材料相互作用特性,摊铺设备与材料相互作用特性。建立了搅拌设备拌和均匀性的数学模型和采用自动调平系统摊铺机的工作装置运动学模型并进行了应用研究。沥青路面施工是由一系列机械设备,通过各单机组合形成的一个有机整体,并相互协调进行规模化生产,实现最佳的工作质量和最优的工作效率。因此要求各机型之间有合理的匹配关系。本论文基于混合料压实的共振理论,研究了碾压过程中材料压实度随压实次数变化的规律,得出了多功能摊铺机振动夯实系统的压实度随摊铺速度变化的数学模型,确定了摊铺机合理的作业区段,建立了以保证作业质量为目标的主要设备、辅助设备与核心设备作业性能相适应的新型匹配关系。由于高性能沥青混合料对施工变异性十分敏感,沥青路面一旦发生变异将严重影响其耐久性和使用寿命。近年来虽然对施工过程中造成路面质量变异性的原因以及相应的处理措施进行了研究,但缺乏全面性、系统性,忽视了设备对施工变异性的影响。本文从材料特性、机械性能及其相互作用特性上研究了沥青混合料设计、生产、运输、摊铺、碾压全过程的材料离析、温度离析和压实离析现象与机理,提出了预防与控制的技术途径和离析的判别标准体系。以上研究成果已在多条高速公路实体工程中得到应用。本文将理论研究与工程实践紧密结合,分别在“襄十”高速公路、“汉宜”高速公路和“老集”高速公路进行了试验验证及广泛的推广应用。结果表明:研究成果对预防与控制沥青路面早期病害,提高施工质量,增加路面耐久性等方面效果十分显著。更多还原

【Abstract】 Freeway development in China is in a high speed stage.However,early damage of asphalt pavement is still a serious problem due to the lack of reservation of related technologies,heavy traffic and the overweight vehicles.The investigation shows that causes which led to the early damage of asphalt pavement are complex problems which have much to do with the type of pavement structure,mixture proportion design,construction techniques and so on,besides the environment and the loading conditions.In recent years,studies have been made on asphalt pavement structure and the mixture proportion design,also laboratory tests showed good combination property,but the problems of the early damage of pavement still exist in the construction,design of pavements directly adopted advanced foreign technologies are not as good as expected.Engineering practice shows that factors such as construction property of mixture,equipment performance,match relations between equipments, interaction property between equipment and material are important to ensure and to improve pavement quality.The above mentioned issues based on systematic theory study and engineering application are concentrated in the paper.Different aggregate gradations form different organization structures in asphalt mixture,structure status of mixture,volume characteristics and construction characteristics.All of theses govern the functional performance of the pavement. Since the gradation and property of high performance asphalt mixture are different from the traditional mixture in terms of gradation and property,the author analyzed and studied many problems about high performance mixture,which include gradation feature parameter control,factors that impact the volume property,construction quality control and so on,proposes construction control scope to ensure excellent property of the mixture.The functions of the machinery equipment should be selected and the parameters should be set up according to the concrete operation object to meet the needs of various pavement structures,material composition and environment requirement and full play of operational characteristics also should be made.The author probed deeply into the structure principle operation characteristics of the main equipments and the factors impacting the equipment property of the key equipment in the construction of asphalt pavement,and put forward the main control indices.The interaction between mixing equipment,paving equipment,compaction equipment and materials were also studied.A uniformity mathematical model for the mixing equipment and kinematics model for the automatic leveling device of the paver is set up.Asphalt pavement construction is an organic whole consisting of a series of machinery equipments combined by individual machine,which run coordinately on a large scale to achieve the best working quality and efficiency.Therefore,a reasonable matching relation between different machines is expected.Based on mixture compaction resonance theory,the author explored the changing regularity of the material compaction degree and compaction times,and sets up a mathematics model for the vibration rammer of the multifunction paver.The model shows that compaction degree of pavement varies with the paving speed,determining the rational range of accommodation for the paver,and sets up the new matching relations for the key equipment,the auxiliary equipment and the core equipment so that they can match each other very well,thus to ensure the operation quality.High performance asphalt mixture is very sensitive to construction variability. Once changes happen to the asphalt pavement,it will seriously influence the durability and the service life.In recent years,although studies on the reason that caused pavement quality variability and the corresponding measures have been carried out,there is still a lack of researches which are studied in a systematic way, and the impact of equipment on construction variability is often neglected.This paper studied segregation phenomenon and its mechanism in the whole process including design,production,transportation,paving and compaction of asphalt mixture,and proposed technical approaches for preventing and controlling segregation and evaluation standard,on the basis of material property,mechanical performance and interaction characteristics.These results have been applied in practical engineering.The study team aims to combine the theory study with the engineering practice, and trial performance have been carried out in "Wuhan-Yichang "freeway and "Laoyemiao-Jining"freeways respectively.The study shows that the research results have a remarkable effect on the prevention and control of early disease of pavement, improvement of construction quality and pavement durability.更多还原