不同养护条件下内养护补偿收缩砂浆性能研究

研究了28 d干燥、保湿7d后干燥、密封三种干燥条件下复掺高倍吸水树脂(SAP)与MgO膨胀剂对砂浆性能的影响.研究结果表明:在以上三种条件下,复掺均能降低砂浆的收缩变形、提高砂浆7d和28 d的抗折强度、抗压强度和抗冻性.复掺在每种干燥条件下对砂浆性能影响不同,密封条件的收缩变形最小,保湿7d后干燥的抗折强度与抗压强度最大、抗冻性最好.复掺氧化镁膨胀剂掺量为8％时减缩效果最好,强度与抗冻性较单掺SAP砂浆有所提高.

Performance of Internal Curing and Shrinkage Compensating Mortar under Different Drying Conditions

Performance of mortar which mixed with high super-absorbent polymer (SAP) and magnesia expansive agent under 28 d drying,wet maintenance 7 d then drying,closed condition were studied.The results show that super-absorbent polymer (SAP) combined with magnesia expansive agent can not only reduce the shrinkage deformation but also improve flexural strength,compressive strength and frost resistance in the above three drying conditions.The influence of the blending on the mortar's properties under varied conditions is different.The shrinkage deformation in close condition is smallest than others;the flexural strength and compressive strength and the frost resistance is the best when the mortar under wet maintenance 7 d then drying condition.The effect of shrinkage reduction is the best,and the strength and frost resistance are higher than that of SAP mortar when mixing magnesia expansive agent and the amount of it is 8％.