不同级配沥青混合料压实特性与高温性能相关性

摘要

To analysis the high temperature stability of different gradation asphalt mixture by compac‐tion characteristics ,four indexes were used to study the compaction characteristics of six kinds of as‐phalt mixture made of two kinds bitumen (original and modified bitumen ) and three gradation (coarse、middle、fine) ,including compaction slope ( K )、compaction energy index from beginning to 92% density (CEI92 ) 、compaction energy index from initial number of gyrations (Nini )to 92% density (CEINini-92 ) and number of gyrations to 92% density(N92 ) .Correlation analysis was carried out on the value of the four indexes and the slop of the second stage of the dynamic creep test at 60 ℃ .The re‐sults indicate that the asphalt mixture with more coarse gradation ,the CEI is greater and the it is more difficult to be compacted ,but its high temperature stability is not always better .The relation‐ship between K value and the high temperature stability is good ,and the gradation with litter K value can be chosen which will have better high temperature performance .%为了通过不同级配沥青混合料的压实特性分析其高温稳定性，采用密实度斜率 K、密实度能量指数 CEI92，CEINini－92，92％密实度对应的旋转次数 N92这4个指标研究了普通沥青和改性沥青成型的粗、中、细3种级配共6种沥青混合料的压实特性，并将4个指标值与沥青混合料60℃动态蠕变试验第二阶段的斜率值进行相关性分析。结果表明，级配越粗，密实度能量指数越大，沥青混合料越难压实，但其高温稳定性并一定越好；密实度斜率 K与沥青混合料高温稳定性相关性较好，在沥青混合料级配选择时可选择 K值更小的级配，使沥青混合料具有更好的高温性能。