水工沥青混凝土粘弹性特性试验研究

Experimental Study on Viscoelastic Properties of Hydraulic Asphalt Concrete

为研究水工沥青混凝土的粘弹性特性,开展不同温度和应力条件下的弯曲蠕变试验。利用Burgers模型作为水工沥青混凝土粘弹性力学行为的本构模型,通过最速下降迭代方法对试验数据进行非线性拟合,得到不同试验条件的拟合曲线和Burgers模型参数,分析参数的变化规律。利用Origin多项式拟合功能建立参数随着温度和应力变化的函数关系式,预测水工沥青混凝土蠕变行为。试验结果表明,利用最速下降法优化Burgers模型能够较好地拟合试验曲线,拟合相关系数均大于0.996,特别是在稳定蠕变阶段,拟合曲线与试验曲线最为接近;在应力保持不变的情况下,Burgers模型中各参数随着温度升高而降低;在温度保持不变的情况下,参数E1、E2在整体上随着应力的增大而增大,参数η1、η2随着应力的增大而降低。

In order to study the viscoelastic properties of hydraulic asphalt concrete,bending creep tests under different temperatures and stress conditions were carried out.The Burgers model was used as a constitution model for the viscoelastic mechanical behavior of hydraulic asphalt concrete,and a nonlinear fitting of the test data was carried out by the most rapid descent iteration method to obtain the fitting curves and Burgers model parameters under different test conditions.By analyzing the variation law of the parameters,the function equation of the parameters with temperature and stress was established by using Origin polynomial fitting function.The creep behavior of hydraulic asphalt concrete was predicted.The test results show that the Burgers model optimized by the most rapid descent method can better fit the test curve,and the fitted correlation coefficients are all greater than 0.996,especially in the isokinetic creep stage,the fitted curve is closest to the test curve;Under the condition of constant stress,the parameters of the Burgers model decrease with the increase of temperature;Under the condition of constant temperature,the parameters E_1 and E_2 increase with increasing stress,and the parametersη_1 andη_2 decrease with increasing stress.