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

基于路基压应变指标和疲劳损伤等效原则,提出沥青面层等效温度的概念及其计算公式;分析沥青面层温度状况与路基疲劳寿命的关系,总结基准状况下沥青面层等效温度的规律;引入路基疲劳寿命修正系数,建立基准状况下路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个地区的基准路基疲劳寿命修正系数值,绘制了全国基准路基疲劳寿命修正系数等值线图.随后,建立了简便实用的基准路基疲劳寿命修正系数与年平均气温和月平均气温年极差之间的回归关系式.最后总结了非基准各因素对路基疲劳寿命修正系数的影响规律,给出了近似修正式.

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

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.