冻融循环作用下橡胶颗粒沥青混合料耐久性试验研究

Test and Research on the Durability of Crumb Rubber Asphalt Mixture under the Condition of Freeze-thaw Cycle

以Ac-13连续型密级配为基础，以橡胶颗粒代替部分集料的形式加入到沥青混合料中，制备橡胶颗粒量掺量为l％-3％的橡胶颗粒沥青混合料。在冻融循环条件下测定混合料的空隙率，并进行冻融劈裂试验，研究冻融循环作用下橡胶颗粒沥青混合料的耐久性。试验结果表明：随着冻融循环次数的增加，沥青混合料的劈裂抗拉强度逐步降低，空隙率逐步变大，两者相关性较大；同等条件下，随着橡胶颗粒掺量的增加，沥青混合料的劈裂抗拉强度逐渐降低，空隙率逐渐增大。橡胶颗粒的掺加在一定程度上降低了沥青混合料的劈裂抗拉强度，2％掺量下的橡胶颗粒沥青混合料劈裂抗拉强度比最优。

Based the typed AC-13 dense graded aggregate, 1% - 3% （by weight of dry aggregate）of rubber particles were added to aggregate instead of part of the fine aggregate, the splitting tensile strength and voidage of crumb rubber asphalt mixture under the condition of freeze-thaw cycle were researched. It is shown that the splitting tensile strength decreases and voidage increases with the increase of freezing and thawing cycles, splitting tensile strength and voidage of crumb rubber asphalt mixture has close relation. With the increase of rubber particles con- tent, the splitting tensile strength decreases and voidage increases under the same conditions. Splitting tensile strength of asphalt mixture is reduced to some extent when rubber particles are added to aggregate, the TSR （ tensile strength ratio） is best when rubber particles content attains 2%.