再生骨料性质与原生混凝土强度等级的关系

Study on Relationships Between Original Concrete Strength and Properties of Recycled Aggregates

依据《普通混凝土用碎石或卵石质量标准及检验方法》(JGJ52-2006)研究原生混凝土强度等级与再生骨料性质的关系.结果表明:当原生混凝土强度等级低于C40时,原生混凝土强度等级对再生骨料表观密度影响不大.再生骨料吸水率与砂浆含量随原生混凝土强度等级升高分别呈相关性很好的指数式与线性降低.而当原生混凝土强度等级不同时,影响再生骨料吸水率的主要因素为再生骨料的砂浆含量与表观密度,二者影响程度之比为1.5.因此,制备高性能的再生骨料混凝土宜采用较高强度等级的废弃混凝土制备再生骨料.原生混凝土强度等级应为再生骨料质量分类考核指标之一.

In this paper, relationship between original concrete strength and properties of recycled aggregates was investigated based on quality standards and testing method of gravel or pebbles used for ordinary concrete（ JGJ52 -2006）. Results indicate that when original concrete strength is below C40, the strength has a little effect on bulk density of recycled aggregates. Water absorption and mortar content of recycled aggregates exponentially and linearly decreases with increase of original concrete strength, respectively. In the case of different original concrete strength, major factors influencing water absorption of recycled aggregates are its mortar content and bulk density, of recycled aggregates concrete and effect degree ratio of the former to the latter is 1.5. Therefore, preparation with high performance using original concrete with relatively strength is appropriate. Original concrete strength should be one of index for quality of recycled aggregates.