采用正交试验,以14 d 一次抗渗压力和28 d二次抗渗压力提升率为评价指标,确定了硅酸钠、碳酸钠、偏铝酸钠和催化剂4种活性物质的最优组合,并采用XRD、SEM和EDS对其水化产物进行了分析.研究结果表明:最优组合A3B2C1D3的14 d一次抗渗压力为1.38 MPa,比基础空白试件相比提升了 112.3％;最优组合为A2B3C2D4的二次抗渗压力提升率为31.42％;XRD分析表明水化产物中未出现新的特征峰,亲氧化钙含量减少,水化硅酸钙凝胶增多;SEM和EDS分析表明活性物质能够在氢氧化钙表面和裂缝中生成大量的絮状水化硅酸钙凝胶,封堵了水化产物中的微裂纹和毛细孔,水化产物中硅元素含量增加,钙元素含量下降,C和Al略微增加.
Research on the influence of active chemicals on the surface impermeability of concrete
Using orthogonal experiments,the optimal combination of four active substances,sodium silicate,sodium carbonate,sodium metaaluminate,and catalyst,was determined based on the evaluation indicators of 14 d primary impermeability pressure and 28 d secondary impermeability pressure improvement rate.XRD,SEM,and EDS were used to analyze their hydration products.The research results show that the optimal combination A3B2C1D3 has a 14 day impermeability pressure of 1.38 MPa,which is 112.3％higher than the basic blank speci-men;The optimal combination of A2B3C2D4 has a secondary impermeability pressure increase rate of 31.42％;XRD analysis showed that there was no new characteristic peak in the hydrated product,the content of calcium oxide was reduced,and the content of hydrated calcium silicate gel was increased;SEM and EDS analysis showed that the active substance could generate a large amount of flocculent calcium sili-cate hydrate gel on the surface of calcium hydroxide and in the cracks,blocking the microcracks and pores in the hydration products.The con-tent of silicon in the hydration products increased,the content of calcium decreased,and the content of C and Al slightly increased.
万方数据
维普
