聚丙烯纤维橡胶混凝土的抗冻性能及损伤劣化模型

Frost resistance and damage degradation model of polypropylene fiber rubber concrete

为提高寒冷地区橡胶混凝土路面的抗冻性能,延长其服役寿命,研究聚丙烯纤维掺量对橡胶混凝土抗冻性能的影响。结果表明:试件质量损失率在冻融初期呈负增长,相对动弹性模量和强度随冻融循环次数的增加均逐渐降低;聚丙烯纤维能提高橡胶混凝土的抗冻性能,对试件抗拉强度的提高效果优于抗压强度。根据损伤力学,定义了聚丙烯纤维橡胶混凝土的冻融损伤程度,并基于相对动弹性模量、抗压和抗拉强度建立了冻融损伤劣化模型,该模型能准确预测聚丙烯纤维橡胶混凝土的冻融损伤劣化规律。

In order to improve the frost resistance of rubber concrete pavement in cold area and extend its service life,the effect of fiber content on the frost resistance of rubber concrete.The results show that the mass loss rate increases negatively at the early stage of freezing-thawing,and the relative dynamic elastic modulus and mechanical strength decrease gradually with the increase of freezing-thawing times.Polypropylene fiber can enhance the frost resistance of rubber concrete,and the improvement effect of fiber on tensile strength of specimens is better than that of compressive strength.According to damage mechanics,the freezingthawing damage degree of Polypropylene fiber rubber concrete was defined,and the freezing-thawing damage degradation model was established based on the relative dynamic elastic modulus and compressive tensile strength,which could accurately predict the freezing-thawing damage degradation law of polypropylene fiber rubber concrete.