The main purpose of this article is to choose among advanced rheological models used in the French rational design, one that best represents the viscoelastic behavior of asphalt mixtures mixed with aggregates of Seneg...The main purpose of this article is to choose among advanced rheological models used in the French rational design, one that best represents the viscoelastic behavior of asphalt mixtures mixed with aggregates of Senegal. The model chosen will be the basis for the development of computational tools for stress and strain for Senegal. However, the calibration of these models needs complex modulus test results. In opposition to mechanical models the complex modulus can directly characterize the viscoelastic behavior of bituminous materials. Here determination is performed in the laboratory by using several types of tests divided into two groups: homogeneous tests and non-homogeneous tests. The choice of model will be carried out by statistical analysis through the least squares method. To this end, a study was carried out to “Laboratory of Pavement and Bituminous Materials” (LCMB) with asphalt concrete mixed with aggregate from Senegal named basalt of Diack and quartzite of Bakel. In this study, the test used to measure the complex modulus is the Canadian test method LC 26-700 (Determination of the complex modulus by tension-compression). There mainly exist two viewing complex modulus planes for laboratory test results: the Cole and Cole plane and the Black space. The uniqueness of the data points in these two areas means that studied asphalt concretes are thermorheologically simple and that the principle of time-temperature superposition can be applied. This means that the master curve may be drawn and that the same modulus value can be obtained for different pairs (frequency-temperature). These master curves are fitted during the calibration process by the advanced rheological models. One of the most used software in the French rational design for the visualization of complex modulus test results and calibration of rheological models developed tools is named Visco-analysis. In this study, its use in interpreting the complex modulus test results and calibration models shows that, the studied asphalt concretes are thermorheologically simple, because they present good uniqueness of their Black and Cole and Cole and Black diagrams. They allow a good application of the principle of time temperature superposition. The statistical analysis of calibration models by the least squares method has shown that the three studied models are suitable for modeling the linear viscoelastic behavior of asphalt mixtures formulated with the basalt of Diack and the quartzite of Bakel. Indeed their calibration has very similar precision values of “Sum of Squared Deviation” (SSD) about 0.185. However, the lower precision value (0.169) is obtained with the 2S2P1D model.展开更多
沥青混合料的黏弹性性能与温度、时间及其胶结料的状态等参数密切相关,而在路面的使用过程中沥青容易受到老化的影响,进一步影响沥青混合料的黏弹性性能。为了让路面设计过程中的参数更为具体,在实验室内对不同老化状态下的SBS改性沥青...沥青混合料的黏弹性性能与温度、时间及其胶结料的状态等参数密切相关,而在路面的使用过程中沥青容易受到老化的影响,进一步影响沥青混合料的黏弹性性能。为了让路面设计过程中的参数更为具体,在实验室内对不同老化状态下的SBS改性沥青混合料进行多个频率及温度下的单轴动态模量试验。采用William, Landel and Ferry(WLF)公式对不同温度下的频率进行时温等效转换,然后基于分数阶模型(2S2P1D模型)建立了动态模量及相位角主曲线,分析老化对沥青混合料黏弹性能的影响特征。研究结果表明:2S2P1D模型能够较好地拟合不同老化状态下的SBS改性沥青混合料的动态模量的数据,相关系数大于0.9;沥青混合料的2S2P1D模型中的玻璃态模量Eg和与粘度相关的β参数随着老化程度的增加显著增大。然而,静态模量E0、分数阶指数k及h随着老化程度的增加而减小。基于该模型建立的储存模量及损失模量的主曲线表明:低频时老化对于沥青混合料的储存模量及损失模量具有不同的影响,当频率趋近于0时,老化对储存模量的影响基本不存在,但是随着老化程度的加深损失模量会显著增强。展开更多
文摘The main purpose of this article is to choose among advanced rheological models used in the French rational design, one that best represents the viscoelastic behavior of asphalt mixtures mixed with aggregates of Senegal. The model chosen will be the basis for the development of computational tools for stress and strain for Senegal. However, the calibration of these models needs complex modulus test results. In opposition to mechanical models the complex modulus can directly characterize the viscoelastic behavior of bituminous materials. Here determination is performed in the laboratory by using several types of tests divided into two groups: homogeneous tests and non-homogeneous tests. The choice of model will be carried out by statistical analysis through the least squares method. To this end, a study was carried out to “Laboratory of Pavement and Bituminous Materials” (LCMB) with asphalt concrete mixed with aggregate from Senegal named basalt of Diack and quartzite of Bakel. In this study, the test used to measure the complex modulus is the Canadian test method LC 26-700 (Determination of the complex modulus by tension-compression). There mainly exist two viewing complex modulus planes for laboratory test results: the Cole and Cole plane and the Black space. The uniqueness of the data points in these two areas means that studied asphalt concretes are thermorheologically simple and that the principle of time-temperature superposition can be applied. This means that the master curve may be drawn and that the same modulus value can be obtained for different pairs (frequency-temperature). These master curves are fitted during the calibration process by the advanced rheological models. One of the most used software in the French rational design for the visualization of complex modulus test results and calibration of rheological models developed tools is named Visco-analysis. In this study, its use in interpreting the complex modulus test results and calibration models shows that, the studied asphalt concretes are thermorheologically simple, because they present good uniqueness of their Black and Cole and Cole and Black diagrams. They allow a good application of the principle of time temperature superposition. The statistical analysis of calibration models by the least squares method has shown that the three studied models are suitable for modeling the linear viscoelastic behavior of asphalt mixtures formulated with the basalt of Diack and the quartzite of Bakel. Indeed their calibration has very similar precision values of “Sum of Squared Deviation” (SSD) about 0.185. However, the lower precision value (0.169) is obtained with the 2S2P1D model.
文摘沥青混合料的黏弹性性能与温度、时间及其胶结料的状态等参数密切相关,而在路面的使用过程中沥青容易受到老化的影响,进一步影响沥青混合料的黏弹性性能。为了让路面设计过程中的参数更为具体,在实验室内对不同老化状态下的SBS改性沥青混合料进行多个频率及温度下的单轴动态模量试验。采用William, Landel and Ferry(WLF)公式对不同温度下的频率进行时温等效转换,然后基于分数阶模型(2S2P1D模型)建立了动态模量及相位角主曲线,分析老化对沥青混合料黏弹性能的影响特征。研究结果表明:2S2P1D模型能够较好地拟合不同老化状态下的SBS改性沥青混合料的动态模量的数据,相关系数大于0.9;沥青混合料的2S2P1D模型中的玻璃态模量Eg和与粘度相关的β参数随着老化程度的增加显著增大。然而,静态模量E0、分数阶指数k及h随着老化程度的增加而减小。基于该模型建立的储存模量及损失模量的主曲线表明:低频时老化对于沥青混合料的储存模量及损失模量具有不同的影响,当频率趋近于0时,老化对储存模量的影响基本不存在,但是随着老化程度的加深损失模量会显著增强。
