水泥-粉煤灰-水玻璃注浆材料强度影响因素试验研究

Experimental study on the influence factors of strength of cement-fly ash-water-glass grouting material

为研究不同配比水泥-粉煤灰-水玻璃注浆材料结石体抗压强度的变化规律,在正交实验设计原则指导下,确定了影响浆液性能的水固比、粉煤灰掺量、水玻璃添加比例三个因素以及各因素的水平,设计了正交实验方案,测试了结石体抗压强度。通过极差和方差分析了各因素对抗压强度的影响规律,最终得出水固比0. 8∶1、粉煤灰掺量20%、水玻璃添加比1%的浆液结石体强度性能最好。采用多元非线性回归法建立结石体28d强度与三因素之间定量关系的基础上,分析浆液固化过程和结石体SEM图像,阐明了三因素对结石体强度的影响机理,认为粉煤灰掺量超过20%会减少氢氧化钙(CH)六方晶体的析出,水固比的增大会稀释浆液,直接导致浆液凝结速度变缓,水玻璃添加比过大一方面会导致浆液凝结过快,其他物料不能充分反应,另一方面会抑制氢氧化钙(CH)的生成,导致强度降低。

In order to study the changing rules of compressive strength of stone with different proportions of cement-fly ash-water glass grouting material,the water-solid ratio,the fly ash content,the proportion of sodium silicate and the level of each factor which affect the performance of slurry were determined in this paper based on the principles of orthogonal experimental design. Moreover,the orthogonal experimental scheme was designed and the compressive strength of the stone body was tested. It is concluded that the strength performance of slurry stone body with a water-solid ratio of 0. 8: 1 and a fly ash content of 20% and a sodium silicate content of 1% is the best by analyzing the influence of various factors on compressive strength. Based on establishing the quantitative relationship between 28d strength of stone body and three factors using multivariate nonlinear regression method,the slurry curing process and SEM images of stone bodies was studied and the three factors the influence mechanism of the strength of stone body was illustrated. It is shown through the study that when the fly ash content is more than 20% will decrease that precipitation of calcium hydroxide ( CH) hexagonal crystals,and the increasing of water-solid ratio will dilute the slurry,resulting the slurry coagulation speed becomes slow directly. On the one hand,excessive addition ratio of sodium silicate will lead to excessive slurry condensation and insufficient reaction of other material; on the other hand,the formation of calcium hydroxide ( CH) is inhibited,resulting in a decrease in strength.