【作者】 陈森；

【导师】 李洪霞； 唐伯明；

【作者基本信息】 重庆交通大学 ， 道路与铁道工程， 2011， 硕士

【摘要】 FWD是二十世纪七十年代末期发展起来的路面无破损弯沉技术,其测速快,精度高,操作方便。FWD检测的完整的弯沉盆信息为分析路面结构层材料性能提供了基础。目前我国公路部门有130多台FWD,由于缺乏相应的技术标准和统一的检测方法,相应造成测试数据的客观性、代表性与准确性得不到有力保证,影响其推广和应用。本文依托西部交通科技建设项目《沥青路面设计指标和参数研究—沥青路面结构性能评价》,通过对比分析国内外的FWD检测方法、实际检测中的经验和对FWD应用单位进行调研,制定了适合我国的FWD标准检测规程。利用室外足尺试验段温度测试数据,得出不同天气情况(晴天、多云、阴天)的温度场变化规律和温度梯度变化规律。对比国内外现有沥青路面代表温度预估方法,得出Bells3公式适用于我国沥青路面代表温度预估的结论。通过分析不同天气情况(晴天、多云、阴天)下的温度数据,利用统计方法得出沥青路面代表温度简单预估公式。温度对沥青路面的承载能力和使用性能有显著影响。在高温气候环境下,沥青混凝土路面发生软化现象,造成整体弯沉值变大,模量降低。低温气候环境下,沥青混凝土发生硬化现象,造成整体弯沉值变小,模量提高。因此,FWD实测弯沉值应当修正到标准温度或其它代表温度下的弯沉值。将沥青路面按土基模量、基层模量、基层厚度、面层厚度分为若干亚类,利用BISAR3分析各亚类沥青路面弯沉温度修正系数,分查表法和公式法两种方法得出沥青路面弯沉修正方法,并利用试验路验证了修正公式的准确性。对沥青路面FWD弯沉指标进行分类,对每一种弯沉盆指标进行相关性分析,得出弯沉比指标DRi适合修正沥青路面FWD其它点弯沉的结论。同时,得到了沥青路面FWD其它点弯沉修正公式。更多还原

【Abstract】 Nondestructive deflection testing using falling weight deflectometer has developed since late seventies of the twentieth century ,which has features of fast testing speed ,high precision and easy operation . The complete deflection basins testing by FWD provide the basis of analyzing pavement layer material properties. Currently there are more than 130 FWDS using by China’s road departments,however ,due to lack of appropriate standards and uniform testing methods ,the objectivity,representativeand accuracy have not an effective guarantee which affect use and promotion of FWDs.This paper,supported by the item of“Study on the Indicators and Parameters-Structural performance evaluation of Asphalt Pavement”,Which sponsored by Western Communications Construction Scientific and Technological Project.By comparing and analyzing FWD testing methods at home and abroad ,plus with the experience of actual FWD detection and visiting the FWD using units ,the FWD standard testing protocol for China is formulated.By using the data of full-scale test section,the variation trend of temperature field and temperature gradient in different weather condition(sunny,overcast,cloudy) is obtained. Through comparison of exsiting asphalt pavement temperature predicting methods at home and abroad, Bells3 model can be used in China’s asphalt pavement temperature prediction.By analyzing the temperature data using statistical method in different weather condition(sunny,overcast,cloudy),the simple temperature prediction model is established.Temperature has significant influece for the asphalt pavement.At high temperature,the asphalt concrete softening phenomenon occurs ,resulting in larger overal deflection and smaller modulus.At low temperature,the asphalt concrete hardening phenomenon occurs,resulting in smaller overal deflection and larger modulus.Thus,FWD testing defelction data should be corrected to the standard data at standard temperature or other representative temperature. The asphalt pavement can be devided into several subgroups based on subgrade modulus,base modulus,base thickness and surface layer thickness.The asphalt pavement deflection correction method containing table method and formula method are obtained by using BISAR3 to analyzing various asphalt pavement deflection pavement correction factor.At last,classify the deflection basin indicators,and then do correlation index analysis of each indicators,the conclusion of DRi is more suitable to correct the FWD other point deflection is gained.Meanwhile,the FWD other point deflection correction methods is established.更多还原