水泥乳化沥青砂浆的静态热机械性能及拟合模型

Static Thermo-Mechanical Properties and Fitting Model of Cement and Asphalt Mortar

为了获得水泥乳化沥青砂浆(CA砂浆)的静态热机械性能,采用德国GABO公司生产的动态热力学谱仪EPLEXOR500 N系统研究了CA砂浆在–40~60℃的温度范围内和0.1 MPa的恒定荷载下变形随温度的发展规律。结果表明:CA砂浆的变形随着温度的升高逐渐增大,整体变形可分为减速变形阶段和变形速率相对稳定的第1、第2匀速变形阶段;当温度相同时,CA砂浆的变形随着沥青和水分含量的增大而增大;当沥青/水泥比由0.3增加到0.9和水/水泥比由0.63增加到0.83时,由减速变形阶段进入第1匀速变形阶段的转变温度T1分别由–30.1℃升高到–27.2℃和由–31.3℃升高到–21.7℃;当沥青/水泥比由0.3增加到0.9,由第1匀速变形阶段进入第2匀速变形阶段的转变温度T2由33.3℃降低到15.6℃,当水/水泥比由0.63增加到0.83时,T2由15.6℃升高到17.9℃。建立了CA砂浆的静态热机械模型,模型拟合结果与试验结果的相关系数均大于0.97,能够有效体现转变温度T2随沥青和水分含量的变化规律。模型参数较少,可为CA砂浆变形性能的温度依赖性提供有效预测。

In order to obtain the static thermo-mechanical properties of cement and asphalt mortar(i.e., CA mortar), the deformation of CA mortar at –40–60 ℃and 0.1 MPa was investigated by means of a GABO dynamic mechanical thermal spectrometer. The results show that the deformation of CA mortar increases with increasing temperature. The total deformation can be divided into the deceleration stage, the first and second uniform deformation stages. The deformation of CA mortar gradually increases with increasing the asphalt and water contents at a certain of deformation rate. When asphalt to cement increases from 0.3 to 0.9 and water to cement increases from 0.63 to 0.83, the transition temperature T1, at which the attenuation deformation stage is transformed into the first stable deformation stage, increases from –30.1 ℃ to –27.2 ℃ and from –31.3 ℃ to –21.7 ℃, respectively. When asphalt to cement increases from 0.3 to 0.9, the T2 at which the first stable deformation stage is transformed into the second stable deformation stage decreases from 33.3 ℃ to 15.6 ℃, when water to cement increases from 0.63 to 0.83, T2 increases from 15.6 ℃ to 17.9 ℃. The predicted data by the proposed static thermo-mechanical model are similar to the experimental results at a correlation coefficient of >0.97, which can effectively reflect the variation of T2 with asphalt and water contents. The model can effectively predict the the deformation performance of CA mortar at different tempertures.