基于土基压应变指标的沥青面层等效温度及疲劳寿命修正系数

Equivalent Temperature for Asphalt Surface Layer and Modified Coefficient to Fatigue Life Based on Subgrade Compression Strain

摘要:

基于土基压应变指标和疲劳损伤等效原则，提出了沥青面层等效温度的概念及其计算式；分析了沥青面层温度状况与土基疲劳寿命的关系，总结了基准状况下沥青面层等效温度的规律；引入了土基疲劳寿命修正系数，建立了基准状况下土基疲劳寿命修正系数 与地区海拔、路表温度年均值及标准差之间的回归式，据此推算得到全国738个地区的 值，绘制了全国 等值线图；随后，建立了简便实用的基准土基疲劳寿命修正系数 与二个常见的气象参量：年平均气温和月平均气温年极差之间回归关系式；最后总结了非基准各因素对土基疲劳寿命修正系数的影响规律，给出了近似修正式。

Abstract:

Based on subgrade compression strain index and the equivalency principal of cumulative fatigue damage, conception and calculation method of equivalent temperature for asphalt surface layer were put forward. The relationship between the temperature condition of asphalt surface layer and subgrade fatigue life was analyzed. The law of equivalent temperature for asphalt surface layer was summarized. By introducing modified coefficient to subgrade fatigue life, regression formula among modified coefficient , the altitude of asphalt pavement located, pavement surface average temperature and its standard deviation over the years was established. Accordingly, modified coefficients at 738 areas in China were calculated and a contour map of was draw. Then simple and practical regression formula between modified coefficient and two common meteorological parameters: annual average temperature and difference of the highest and lowest monthly average temperature was established. Finally, the influence rules of various factors on modified coefficient to subgrade fatigue life were summarized and approximate modified formula was given.