【作者】 童琴；

【导师】 陈华鑫；

【作者基本信息】 长安大学 ， 道路与铁道工程， 2011， 硕士

【摘要】 为防止或延缓旧水泥路面加铺沥青面层、新建路面半刚性基层或刚性基层因后期产生温缩、干缩裂缝而引发的路面早期反射裂缝问题,课题组研发了SAMPAVE应力吸收层。该功能层采用特种改性沥青和特定矿料级配制成,沥青含量高达9%,形成富沥青砂粒式沥青混合料。SAMPAVE应力吸收层混合料设计方法有别于其它类型混合料,采用常用的马歇尔法和Superpave法进行混合料设计都存在一定的缺陷,因此,对于SAMPAVE应力吸收层混合料设计方法的研究须摆脱传统思维,另辟蹊径,合理确定沥青用量对其大面积推广应用具有重要的意义。论文对比了分形理论、比表面积因子法、表面积指数法、隔离膜方法等四种比表面积理论计算方法的特点,建立了基于分形理论的SAMPAVE应力吸收层混合料比表面积计算模型。并对比了三种实测比表面积的方法(氮吸附法、粒度分析法、勃氏透气法),发现氮吸附法测试矿料比表面积较为合适,且分形理论模型计算值与实测值较为相近。然后分析了沥青膜厚对混合料性能的影响,综合应力吸收层混合料各项性能指标,确定应力吸收层混合料的合理三维膜厚为12-13μm。通过确定矿质混合料总比表面积,考虑最佳沥青膜厚时有效沥青含量及矿料所吸收的沥青量,得出SAMPAVE应力吸收层混合料沥青用量预估值。采用本文模型对青兰高速和武黄高速铺筑应力吸收层路段工程资料的验算,发现预估模型具有较好的可靠性和适用性。更多还原

【Abstract】 In order to prevent and reduce early reflected crack produced by semi-rigid base or rigid base’s temperature shrinkage or dry crack in the overlay of old cement concrete pavement, the new construction, the SAMPAVE Stress Absorbing Layer is developed. This function layer adopts the special modifying asphalt and the specific mineral aggregate gradation, the asphalt content reaches as high as 9%, forms the rich asphalt sand grains type bituminous mixture. The SAMPAVE stress absorbing layer mixture design method is different from other type mixture, and the commonly used Marshall method and the Superpave method for this type mixture design have some shortcomings. Therefore, the research of mixture design method for the SAMPAVE stress absorbing layer should get rid of traditional thought and tries another path. Reasonably determing the asphalt content for the SAMPAVE stress absorbing layer’s mixture design has the vital significance for its wide application.This paper has contrasted four theoretical calculation method for specific surface area (including fractal theory method, specific surface area factor method, surface area index method, isolating membrane method), and established the surface area calculation model based on the fractal theory for the SAMPAVE stress absorption layer mixture. Then three measurement methods of specific surface area (BET method, grain size analysis, blaine method) is compared, found that the BET method to test mineral aggregate’s specific surface area is more appropriate than others, and the fractal theoretical model predicted value and the actual value are closer. After that, the asphalt film thickness of asphalt mixture influence on the mixture performance is analyzed, considering all of mixture performance index of SAMPAVE stress absorbing layer comprehensively, the reasonable three dimensional film thickness is recommend about 12～13μm. According to determination of mineral mixture’s total specific surface area, considering the effective asphalt content and the absorbing the asphalt content by mineral aggregate at the best asphalt film thickness, the asphalt amount estimation velue of SAMPAVE stress absorbing layer mixture is obtained. Through checking calculation on engineering datas of the stress absorbing layer section in Qing-Lan highway and Wu-Huang highway with this model, it is discovered that the prediction model has a good reliability and the applicability.更多还原