聚合物改性砂浆强度的回弹法检测试验研究

Detection experimental study on rebound method for polymer-modified cement mortar strength

采用L9(34)正交试验研究了胶粉掺量、水胶比、灰砂比以及硅粉掺量对聚合物改性砂浆表面硬度和抗压强度的影响,通过对散点图的拟合分析确定了聚合物改性砂浆抗压强度与回弹推定值的相关关系.结果表明,各因素对抗压强度和回弹推定值的影响主次顺序一致,影响因素顺序由大到小为胶粉掺量、水胶比、硅粉掺量、灰砂比;抗压强度随胶粉掺量、水胶比的增大而减小,随硅粉掺量和灰砂比的增加而增大;聚合物改性砂浆抗压强度与回弹推定值之间存在线性正相关关系,且在显著性水平α=0.01下其相关关系显著.

The L9 （34） orthogonal test was adopted to study the influences of the amount of rubber powder, water-binder ratio, the content of silica powder and cement-sand ratio on surface hardness and compressive strength of polymer-modified mortars. The correlation between compressive strength and deductive value of springback of polymer-modified mortars is confirmed by fitting and analyzing the scatter plot. The results show that the primary and secondary sequence of the effect of each parameter on compressive strength and deductive value of springback is the same. First comes the amount of rubber powder, next is the water-binder ratio which is followed by the content of silica powder, while the cement-sand ratio has the least influence on it. In terms of the impact trend, the compressive strength decrease with the increase of the amount of rubber powder and water-binder ratio, while increase with the increase of the content of silica powder and cement-sand ratio. There exists a positive linear correlation between compressive strength and deductive value of springback of polymer-modified mortars, and the correlativity is significant when the significant level a is 0.01.