砂浆专用改性剂WD对湿拌砂浆的影响

研究了砂浆专用改性剂WD与细骨料对湿拌砂浆稠度保持、保水率、收缩率、抗压强度、粘结强度等影响。结果表明：掺入专用改性剂WD的湿拌砂浆的粘结强度、稠度保持、保水率等性能明显优于未改性空白砂浆,可保持施工性能24 h以上;细骨料细度模数增大,比表面积变小,胶凝材料更好地包裹细骨料;细颗粒砂改善了砂浆保水性,但细度模数过小会导致砂浆收缩率增加并降低抗压强度;细骨料细度模数2.5时湿拌砂浆综合性能较佳。

Influence of Special Mortar Modifier WD on Physical Properties of Wet Mortar

The influence of special mortar modifier WD and fine aggregate on consistency, water retention rate, contractibility, bonding and compression strength of mortar was studied. From experimental results, it could be concluded that the wet mortar containing modifier and sand with moderate fineness modulus（2.5） showed excellent physical properties, which could maintain its operable ability above 24 h. With the increase of fineness modulus for sand, its specific surface area decreased, and then the fine aggregate were coated well with cementing material. However, when fineness modulus of sand of mortar was too low, its contractibility increased and compression strength decreased.