再生细骨料及矿物掺合料对再生砂浆强度及微观结构的影响  

The Influence of The Recycled Fine Aggregate and Mineral Admixture on the Microstructure and Strength of Recycled Motar

作　　者：李滢[1] 代大虎[1] 龚志起[1] 

机构地区：[1]青海大学土木工程学院,西宁810016

出　　处：《粉煤灰综合利用》2015年第6期6-9,共4页Fly Ash Comprehensive Utilization

基　　金：青海省科技厅项目(2013-G-209)

摘　　要：将不同来源的2种再生细骨料及矿物掺合料以不同的掺配方式掺入砂浆中,研究了再生砂浆强度及微观结构的变化。研究发现在水泥砂浆中掺入不同来源的再生细骨料后,随着取代率的变化再生砂浆强度表现出的变化趋势不同。在再生细骨料取代率为50%的情况下同时在水泥砂浆中掺加矿物掺合料,无论是单掺粉煤灰还是复掺粉煤灰和硅灰,再生砂浆在水化早期的强度均有明显下降,到了28d时强度均基本接近。从微观结构来看,掺加再生细骨料后,水泥石内部结构中有比较大的孔隙和微裂纹,但如果同时加入矿物掺合料,水泥凝胶体内部的孔隙减少,结构趋于致密。By mixing two series recycled fine aggregates derived from different origins and mineral admixtures into cement mortar, the influence on the microstructure and strength of recycled mortar is studied. It is demonstrated that with the increasing of recycled fine aggregate replacement rate, the change of the strength of the mortar with this two series recycled fine aggregates are different. When the recycled fine aggregate replacement rate is 50%, mixed fly ash and silica fume into recycled mortar separately and jointly, the variation tendency of compressive strength and microstructure were studied. It is demonstrated that the early strength of recycled mortar decreased, but the 28d is very closely. There are many voids and cracks in cement gel when mix recycled fine aggregate into mortar. But if mixed mineral admixtures into recycled mortar together, the microstructure of the cement gel tends to be more dense.

关 键 词：再生细骨料 再生砂浆 水泥石 矿物掺合料 再生细骨料取代率 

分 类 号：TU522.09[建筑科学—建筑技术科学]