高吸水性树脂对混凝土收缩开裂的改善效果试验研究

Experimental study on improving effect of superabsorbent resin on shrinkage cracking of concrete

为了降低收缩率,抑制混凝土发生开裂的概率,通过试验研究高吸水性树脂对混凝土收缩开裂的改善效果。选择单掺丙烯酰胺和丙烯酰胺+丙烯酸复掺两种树脂,分别用树脂种类与用量,验证混凝土抗压强度与内部湿度的影响。通过试验确定树脂用量对于混凝土收缩量影响,以及不同温度处理后,树脂对混凝土开裂情况抑制效果。试验结果显示:丙烯酰胺+丙烯酸复掺的高吸水性树脂吸水率更高,能够显著提升混凝土的抗压强度。单掺丙烯酰胺的树脂制备的混凝土湿度会随养护时长增加而显著上升,但是复掺丙烯酰胺+丙烯酸树脂的混凝土湿度会保持稳定状态。丙烯酰胺+丙烯酸复掺高吸水性树脂用量为0.4%时的混凝土收缩量最小,且该用量下树脂在高温环境下也能一定程度抑制混凝土开裂。

In order to reduce the shrinkage rate and suppress the probability of concrete cracking,the improvement effect of high water absorbent resin on concrete shrinkage cracking was studied through experiments.Select two types of resins,single addition of acrylamide and acrylamide+acrylic acid composite,and verify the effects of resin type and dosage on compressive strength and internal humidity.Determine the effect of resin dosage on concrete shrinkage through experiments,as well as the inhibitory effect of resin on concrete cracking after different temperature treatments.The experimental results show that the water absorption rate of the high water absorbent resin mixed with acrylamide and acrylic acid is higher,which can significantly improve the compressive strength of concrete.The humidity of concrete prepared with a single addition of acrylamide resin will significantly increase with the increase of curing time,but the humidity of concrete mixed with acrylamide and acrylic acid resin will remain stable.The concrete shrinkage is the smallest when the dosage of acrylamide+acrylic acid composite high water absorbent resin is 0.4%,and the resin can also inhibit concrete cracking to a certain extent in high temperature environments at this dosage.