沥青混合料劲度残留值的影响因素试验

Test of Influencing Factors of Stiffness Residual Value of Asphalt Mixture

借助于四点弯曲小梁疲劳试验装置,采用对称循环加载方式,通过加载次数来设置循环,并且在不同的循环次数之间设定相应的恢复时间,研究了多个循环作用下不同的恢复方式、应变大小以及温度的大小与沥青混合料的劲度残留率之间的关系。研究结果表明:小梁在无约束情况时的劲度残留率要大于有约束时的劲度残留率,并且随着循环次数的增加,这两者之间的差值会越来越小。应变越小,则劲度残留率会越大,200με作用下劲度的残留率较大,400με和600με作用下对应的劲度残留率在循环次数少的时候比较接近,随着循环次数的增加,二者之间的差异会明显。温度为5℃和15℃时的劲度残留率比较接近,25℃时的劲度残留率要大于5℃和15℃时的对应的劲度残留率。

By 4-point small beam fatigue test device, adopting the symmetrical cyclic loading method, we analyzed the influence of different restoration modes, strain values and temperatures on stiffness residual percentage of asphalt mixture under several cycles controlled by loading times, between which restoration time is set. The result shows that （1） the stiffness residual percentage of small beam under unconstrained condition is greater than that under constrained one, and with the increase of cyclic times, the difference between them become smaller; （2） the smaller the strain is, the greater the stiffness residual percentage becomes, under the control of 200 με, the value is greater, for 400 με and 600 με, the values of stiffness residual percentage are approximately equal at the beginning, while with the increase of cyclic times, the difference between them becomes greater; （3） the stiffness residual percentages are very close at 5 ℃ and 15 ℃, and it is greater at 25 ℃.