再生砂制备干混砌筑砂浆保水率的研究

Water retention research of mortar which made by the recycled sand

由于施工现场拌制砂浆的缺点及局限性越来越突出,干混砂浆在技术性能、社会效益等方面的优势得到越来越多人的认可。当利用再生砂制备干混砂浆时,人们普遍采用旧的规范和试验操作过程,导致再生砂制备的干混砂浆泌水现象严重,不能满足砂浆的保水率要求。针对再生砂本身粒径级配较差、内部裂缝较多的弱点,通过改变保水增稠剂的用量、调整胶凝材料比例和改变细骨料粗细程度来研究再生砂所制备干混砂浆的保水性能。试验结果表明:增加保水剂的用量可以显著的提高砂浆保水率;固定水泥用量,通过增加粉煤灰的掺量在一定范围内可以较好的提高砂浆保水率,并且还可以减少砂浆的稠度损失;细度模数小的再生砂可以适当提高砂浆的保水率。

Due to the shortcomings and limitations is more and more prominent of field mixing mortar,the advantage of dry mortar in such aspects as technical performance and social benefit been recognized by more and more people.It is widely used the old specification and test operation when using reclaimed sand mixing dry mortar.That cause the bleeding phenomenon is serious of reclaimed sand mixing dry mortar,and not meet the requirement of the water retention.In view of the weaknesses of reclaimed sand particle size grading and internal cracks.This experiment by changing the dosage of the water retention,adjustment of gelled material proportion and the degree of fine aggregate thickness to research the water performance of recycled dry mortar.The results show that：increase the amount of water retention agent can significantly improve the slurry water retention;fixed dosage of cement,in a certain range by increasing the dosage of fly ash mortar can improve water retention better,and reduce mortar consistency of loss;small fineness modulus of reclaimed sand can improve the water retention of mortar.