再生微粉和矿渣粉对再生砂浆强度及抗冻性的影响

Effects of recycled fine powder and slag powder on the strength and frost resistance of recycled mortar

针对再生微粉单掺以及再生微粉、矿渣粉复掺对再生砂浆抗压强度及抗冻性的影响进行试验研究,并结合孔结构及SEM电镜试验,对单掺再生微粉以及复掺再生微粉和矿渣粉再生砂浆的抗压强度及抗冻性的特征加以分析。结果表明,控制再生微粉掺量可改善再生砂浆的孔隙结构,其抗压强度及抗冻性可达到甚至超过空白组再生砂浆。总掺量为20%的复掺再生微粉、矿渣粉再生砂浆的孔隙结构更加致密,抗压强度及抗冻性均优于空白组再生砂浆。掺再生微粉及矿渣粉后,水泥的水化产物及碳化产物相应减少。再生微粉掺量为20%的再生砂浆微观结构较疏松,而复掺再生微粉和矿渣粉后再生砂浆的微观结构更加致密。

The effects of the single dosage of recycled fine powder(RFP)and the double dosage of RFP and slag powder on the compressive strength and frost resistance of recycled mortar(RM)are studied.Combining with the test of pore structure and SEM,the compressive strength and frost resistance of RM of the single addition of RFP and the double mixing of RFP and slag powder are analyzed.The results show that controlling the dosage of RFP can improve the pore structure of RM,and the compressive strength and frost resistance can reach or even exceed that of blank RM.The pore structure of the double mixing of RFP and slag powder with a total dosage of 20%is more compact,and the compressive strength and frost resistance are both better than that of blank RM.After adding RFP and slag powder,the hydration products of cement and carbonization products are reduced accordingly.The microstructure of RM with the 20%dosage of RFP is relatively loose,while the microstructure of RM with the double mixing of RFP and slag powder is more compact.