矿渣-粉煤灰地聚物注浆材料配比优化方法研究

Optimization Method of Slag-Fly Ash Geopolymer Grouting Material Ratio

地聚物作为绿色环保、价格低廉的注浆材料,要达到良好可注性需兼顾强度和流动性等注浆性能指标。为此,以液固比、水玻璃掺量和水玻璃模数为试验因素开展室内配比优化试验,构建了抗压强度、流动度和终凝时间的多元二阶响应面回归模型,并通过方差分析获得单因素及其交互作用对各注浆性能指标的影响规律。试验因素对注浆性能指标的影响程度依次为液固比、水玻璃掺量、水玻璃模数,液固比和水玻璃掺量交互作用对抗压强度的影响显著,其余两因素交互作用对注浆性能指标的影响均不显著。采用层次分析法并结合专家赋值法获取各注浆性能指标相对权重,构建多目标满意度函数对矿渣-粉煤灰地聚物注浆材料配比进行优化,据此对注浆性能指标综合最佳配比的浆液结石体进行SEM测试。结果表明,体系中仍能观测到少量球形未反应粉煤灰颗粒,矿渣颗粒和水泥颗粒基本反应完全,低聚态凝胶类反应产物重新排列和沉积延伸,相互交叉搭接构成致密且完整的空间网络状结构。

As a green,environmentally friendly,and cost-effective grouting material,geopolymer requires consideration of grouting performance indicators such as strength and fluidity in order to achieve good injectability.For this reason,indoor ratio optimization experiments were conducted using liquid-solid ratio,water glass content,and water glass modulus as experimental factors.A multivariate second-order response surface regression model was constructed for compressive strength,flowability,and final setting time,and the influences of single factor and its interaction on various grouting performance indicators were obtained through variance analysis.The degree of influence of experimental factors on grouting performance indicators is as follows:liquid-solid ratio,water glass content,and water glass modulus.The interaction between liquid-solid ratio and water glass content has a significant impact on compressive strength,while the interaction between the other two factors has no significant impact on grouting performance indicators.Using the analytic hierarchy process and expert assignment method to obtain the relative weights of various grouting performance indicators,a multi-objective satisfaction function was constructed to optimize the ratio of slag-fly ash geopolymer grouting materials.Based on this,SEM testing was conducted on the slurry stone body with the best comprehensive ratio of grouting performance indicators.The results show that a small number of spherical unreacted fly ash particles can still be observed in the system,the slag particles and cement particles are basically fully reacted,and the oligomeric gel-like reaction products are rearranged and extended by deposition,and cross-lap with each other to form a dense and complete spatial network-like structure.