【摘要】 为研究超吸水聚合物(SAP)对含氧化镁膨胀剂水泥砂浆早期自愈合性能的影响,在掺氧化镁膨胀剂的水泥砂浆中加入经过预吸水处理的SAP,通过对不同损伤程度下的水泥砂浆抗压强度恢复率、毛细吸水率及超声波脉冲速度(UPV)进行试验分析。研究结果表明:复掺SAP与氧化镁膨胀剂的试件抗压强度恢复率较空白组均提高显著,提高幅度约为30%～43%;预压破坏荷载70%及以下的初始损伤试件,在28d时的毛细吸水率更接近未损伤试件,对预压破坏荷载超过70%的初始损伤试件与未损伤试件的毛细吸水率相差接近20%;相同损伤程度下,复掺SAP与氧化镁膨胀剂的试件UPV恢复率较单掺氧化镁膨胀剂的试件提高了10%左右,且随着氧化镁膨胀剂掺量的增加,UPV的恢复率也更为显著。更多还原

【Abstract】 In order to study the effect of superabsorbent polymer(SAP) on the early self-healing performance of cement mortar containing magnesium oxide expansive agent, pre absorbent SAP was added to the cement mortar mixed with magnesium oxide expansive agent, and the compressive strength recovery rate, gross water absorption rate, and ultrasonic pulse velocity(UPV) of cement mortar under different damage levels were tested and analyzed. The results show that the recovery rate of compressive strength of the specimens mixed with SAP and magnesium oxide expander is significantly higher than that of the blank group, with an increase of about 30% to 43%; The capillary water absorption of the initially damaged specimen with a preload failure load of 70% or less is closer to the undamaged specimen at 28 days, and the difference between the capillary water absorption of the initially damaged specimen with a preload failure load of more than 70% and the undamaged specimen is close to 20%; Under the same degree of damage, the UPV recovery rate of the specimen mixed with SAP and magnesium oxide expander is increased by about 10% compared to the specimen mixed with magnesium oxide expander alone, and with the increase of the amount of magnesium oxide expander, the UPV recovery rate is also more significant.更多还原