【作者】 刘建勋；

【导师】 周伟；

【作者基本信息】 长安大学 ， 交通运输工程， 2010， 博士

【摘要】 温拌技术是一种新兴的绿色筑路技术。温拌沥青混合料(WMA)与传统的热拌沥青混合料(HMA)相比,其拌和与压实温度相对较低,能源消耗和废气排放相对较小,并具有较好的路用性能,具有十分广阔的应用前景。然而,温拌沥青混合料在我国的应用时间短,在实际使用中存在室内配合比设计指标和控制指标缺失、拌和与压实温度的确定缺少理论依据、低温环境中能否进行施工不等影响其正确应用的技术问题,本研究依托甘肃省交通科技建设项目“隧道温拌阻燃改性沥青路面施工技术研究”,针对温拌沥青混合料设计和施工中的一系列关键技术问题,在充分调研、理论分析和室内试验的基础上,对下述主要内容展开系统、深入的研究。分析对比了SBS改性沥青以及添加5%的Evotherm-DAT温拌剂的SBS改性沥青的5℃延度、RTFOT5℃延度并对两种沥青进行了SHRP PG(性能分级)试验,测试了添加DAT温拌剂的SBS改性沥青在不同温度下的布氏旋转粘度,探讨了Evotherm-DAT对沥青技术指标的影响。采用马歇尔击实法和旋转压实法成型试件,探讨了不同成型方式下两种混合料空隙率和密度随温度变化的关系,在此基础上选择了适合于温拌沥青混合料的成型方法。提出了压实能量指数CEI和交通密实指数TDI来反映由旋转压实机SGC得到的密实曲线的信息,得到了温拌沥青混合料旋转压实成型时的最佳温度。基于分形几何理论,推导了矿料分布分形模型,并利用定义的Fuzzy分形维数,研究了密级配沥青混合料矿料分形分布特征——分形维数和自相似性。探讨了Superpave分形维数与混合料设计参数、动稳定度、0℃弯曲应变能和疲劳性能等路用性能的关系。基于温拌沥青混合料体积参数特征和路用性能检验结果,提出了温拌混合料设计时的技术指标和沥青混合料路用性能控制指标。根据热传导规律,建立了沥青混合料运输过程中不同部位的温度场分析模型,并根据施工现场温度测定,验证了所建数学模型的可靠性。现场采集沥青路面摊铺时不同时间、不同空间的温度变化情况,研究了沥青混合料摊铺时路面周围温度场的时空分布特性。基于沥青路面导热过程——非稳态导热原理,推导出沥青混合料导温系数的计算公式。通过导温试验测试了所需导温系数参数；分析了不同温度、空隙率对温拌沥青混合料导热系数的影响。依据温度场有限元法建立温拌沥青混合料压实过程的温度场模型,利用ANSYS的热分析功能——瞬态热分析,对压实过程的沥青混合料的降温速率影响因素进行了计算分析；采用灰色关联度分析法对影响温拌沥青混合料的降温速率的各个因素的主次进行了对比分析。根据影响混合料有效压实时间诸因素的特性,提出了基于模糊数学的混合料有效压实时间的多因素模糊综合分析和预估方法。通过实测不同施工环境中温拌沥青混合料在各个时刻的表面温度和内部温度,验证了Pavecool软件预测沥青混合料降温特性的准确性；结合天水和定西两地环境气候特点,采用Pavecool计算得到了不同环境、不同层厚的温拌沥青混合料施工最低环境温度条件。依托天定高速公路沥青路面建设工程,进行了温拌沥青混合料施工工艺研究和节能减排效果的定量分析。结果表明,温拌沥青混合料可以获得较好的路面压实效果；与热拌沥青混合料相比,采用温拌沥青混合料可大大降低在拌和生产过程中所排放出的有害气体；温拌沥青混合料可比相应的热拌沥青混合料节约能耗20%左右。更多还原

【Abstract】 Warm mix of asphalt is a new technology of green road construction. Compared with the traditional hot mix asphalt (HMA), the mixing and compaction temperatures are relatively low, energy consumption and emissions is relatively small and has good road performance for warm mix asphalt (WMA). And it is a new way of energy saving environmentally friendly materials, has very broad application prospects. However, as the time is short in the applications of construction, there are some problems about its application such as no design specifications, lack of theoretical basis for a reasonable mixing and compaction temperatures determined, wether can be constructed in the low-temperature environment. Relying on the transportation construction projects in Gansu Province—Research on pavement construction technology for the warm mix, fire retardant modified asphalt, a series of key technical issues in the design and construction was researched based on the extensive collection and analysis of warm mix asphalt at home and abroad.The agent at 5℃and softening point before and after aging was analyzed and comparised for the SBS modified asphalt and SBS modified asphalt adding 5% Evotherm-DAT. The SHRP PG (performance grade) test was done about two asphalt. At same time, brookfield viscosity was examined for the SBS modified asphalt adding 5% Evotherm-DAT.The relationship of voids and density with molding temperature was discussed using Marshall compaction method and rotary compaction molding specimens. Based on this, the molding method suitable for warm mix asphalt is determined. The densification energy index (CEI) and traffic densification index(TDI) in the construction process are introduced to refect inherent information of asphalt mixture. And the compaction molding temperature was obtained.Based on fractal geometry theory, the fractal characteristics of aggregate distribution composed with fractal dimension and self-similarity in dense-gradation asphalt mixture was researched based on the fractal model of aggregate distribution and fuzzy fractal dimension defined. And the relationship between the fractal dimension(D) and pavement performance was researched by testing volume parameter of mixtures, dynamic stability and bending strain energy at 0℃. The technical indicators in the process of design for the mixture and control indicators of asphalt pavement performance were proposed by the experiment of WMA road performance at the optimum asphalt content.The temperature field analysis model was established in different parts of transport vehicles during transport for asphalt mixture. And the reliability of the mathematical model built was verified by the temperature measurement in the construction site. Space- time Distribution Characteristics of Temperature Field During Asphalt Pavement Paving was researched by the collection of temperature measurement in the construction site.The primary and secondary each factor were compared about cooling rate of warm mix asphalt by the method of gray correlation analysis.Based on the principle of non-state heat conduction in the thermal process of asphalt pavement, thermal diffusivity of asphalt mixture formula was derived. The required parameters thermal conductivity coefficient was obtained by the thermal conductivity tests. Based on this, the effect of different temperature and void on the thermal conductivity coefficient was analyzed. According to finite element method of the temperature field, the temperature field model in the process of warm mix asphalt compaction was built. And the influence factors on cooling rate of warm asphalt mix in the the process of compaction of asphalt pavement was analyzed.Based on the effect of time available for asphalt mixture compaction, a kind of fuzzy analysis is provided by synthesizing all factors.The accuracy of cool features for asphalt mixture predicted was verified by the software of Pavecool through measuring the temperature at the surface and internal asphalt mixture at various times in different environments. Combined with the environmental and climatic characteristics in the Tianshui and Dingxi of Gansu province, the minimum ambient temperature conditions was determined for different thickness and environments of the asphalt mix construction.Relying on pavement construction from Tianshui to Dingxi, the construction engineering technology was studied and energy saving and emission reduction of warm mixed asphalt was quantitatively analyzed. The results showed that asphalt pavement compaction can get better by the warm mix asphalt. Comparing with the HMA, harmful gas emissions of WMA in mixing process can be greatly decreased, and WMA can reduce energy consumption 20% comparing with the corresponding HMA.更多还原