The hot oxygen aging of four kinds of asphalts were carried on rotated thin film oven tests (RTFOT) to characterize basic performance of asphalts before and after aging,and the relationship between aging performance and chemical composition were discussed in detail.It was found that the increase of viscosity was not exponential or linear which were traditionally regarded as,but linear first and accelerated then,and the point of transition was related to asphalt grades.The colloidal instability index (L) was closely associated with aging performance of asphalts,and the higher Ic gave rise to greater change before and after aging.The softening point and viscosity of asphalts were related to number-average molecular weight and colloidal state,and the variations of penetration and ductility had well relationship to light components inside asphalts.The aging process of asphalts was influenced by the content of elemental sulfur,and more content of elemental sulfur caused smaller change of penetration before and after aging.%采用旋转薄膜加热老化试验(RTFOT),对4种不同牌号的沥青进行了热氧老化模拟,对沥青老化前后的各项基本性能进行了表征,并对其老化性能与化学组成之间的关系进行了详细探讨.结果表明,沥青老化过程中,黏度的增长并非传统意义上人们认为的呈指数型或直线型增长,而是先直线增长,到达某一临界点后增长速率加快,且临界点与沥青种类有关.胶体不稳定指数Ix与沥青的老化性能存在密切关联,Ix越大的沥青,老化后性能变化越大.沥青的软化点与黏度都与沥青的数均分子量及胶体结构有关,而针入度与延度的变化则与沥青中轻组分的关系较密切.S元素含量影响沥青的老化过程,S含量大的沥青,老化前后针入度变化小.
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