倪杨洲

将建筑和拆迁垃圾作为骨料回收再利用，不仅可以保护环境，还可以缓解自然资源的短缺。但由于再生骨料破碎值和吸水率较高、表观密度较低等缺点，限制了其在实际工程中的应用。为了拓展再生骨料的应用，本次研究采用沸石粉（Zeolite powder，ZP）、硅灰（Silica fume，SF）和聚乙烯醇（Polyvinyl alcohol，PVA）改性再生粗骨料（Recycled coarse aggregate，RCA）：沸石粉-水泥一次改性、硅灰-水泥一次改性、水玻璃一次改性、沸石粉-水泥+聚乙烯醇二次改性、沸石粉-水泥+水玻璃二次改性、硅灰-水泥+水玻璃二次改性、水玻璃+硅灰-水泥二次改性七种处理方法。结果表明，七种处理方法均能在一定程度上改善RCA的性能。同时，通过扫描电镜观察，处理后的RCA界面过渡区和水泥基体的裂缝宽度也减小。七种处理中，沸石粉复合水泥裹浆结合10%浓度水玻璃溶液二次强化的RCA性能最优，压碎指标为8.03%，较未改性降低了36.5%；吸水率为4.18%，较未改性降低了32.1%。

再生粗骨料；二次改性

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