矿物掺合料作为砂浆细集料的水化产物与光谱性能研究

粉煤灰、锂渣和钢渣作为工业废渣，等质量替代水泥时其利用率往往较低，为了大量地使用这些工业废渣。采用X射线单晶衍射仪、同步热分析仪、傅里叶红外光谱仪和电镜扫描分析方法，研究了锂渣、粉煤灰和钢渣替代细集料后砂浆的水化产物、光谱特性、微观形貌，并探讨了砂浆抗折/抗压强度随替代率(0%，30%，50%，70%和100%)增长的变化规律。研究结果表明：四种浆体的水化产物主要为CSH凝胶、Ca(OH)₂、少量的AFt和未水化的颗粒(Al₂O₃，SiO₂)，其中水泥-锂渣浆体、水泥-粉煤灰浆体、水泥-钢渣浆体中的未水化颗粒还含有一定的Li₂O·Al₂O₃·SiO₂，Ca_1.56SiO_3.5·xH₂O和RO phas。四种浆体以3 467，3 438，2 923，2 348，1 638，1 429，1 111，1 000，768，696和462 cm-1为特征峰，但其峰强有所不同，其活性也不同，参与二次水化反应的程度也不同，因此，水泥-钢渣浆体中Ca(OH)₂的含量明显高于水泥-粉煤灰浆体和水泥-锂渣浆体的现象；但不管是矿物掺合料替代水泥还是细集料，都在浆体中发挥着火山灰活性和填充作用。含三种100%矿物掺合料砂浆的抗折强度和抗压强度均高于纯水泥砂浆，分别(锂渣、粉煤灰和钢渣)约高37.77%/51.88%，14.71%/11.70%，91.95%/34.88%，但其达到峰值的掺量不同。因此，采用矿物掺合料替代细集料是可行的，能大幅度提高工业废渣在混凝土行业中的使用，且能达到节能减排的效果。

Stuay of Mineral Admixtures as Fine Aggregate on Hydration Products and Spectral Performance of Mortar

Fly ash, lithium slag and steel slag as industrial waste, replace quality cement to prepare cement mortar and concrete, but its utilization is often low, so using these industrial waste in large quantities by using X-ray diffraction (XRD), thermal analyzer, Fourier infrared spectrometer and scanning electron microscope analysis method, we studied the hydration products, spectral performance and microstructure of mortar after mineral admixtures as fine aggregate, and the change laws of mortar strength with the replacement rate (0%, 30%, 50%, 70% and 100%) were analyzed. Test results showed that the hydration products were CSH gel, Ca(OH)₂, a small amount of AFt and Four kinds of slurry hydration products mainly for CSH gel, Ca(OH)₂, a small amount of AFt and unhydrated particles (Al₂O₃ and SiO₂) for cement paste, cement-lithium slag paste, cement-fly ash paste, cement-steel slag paste, which contain a certain Li₂O·Al₂O₃·SiO₂, Ca_1.56SiO_3.5·xH₂O, and RO phase, respectively. Characteristic peak was 3 467, 3 438, 2 923, 2 348, 1 638, 1 429, 1 111, 1 000, 768, 696 and 462 cm-1 for four paste, but its strong peak was different and activity was also different, which was involved in the level of secondary hydration reaction is also different, so the content of Ca(OH)₂ in cement-steel slag paste was significantly higher than cement-lithium slag paste and cement-fly ash paste. It played volcanic activity and filling effect when mineral admixtures replaced cement or fine aggregate. The flexural strength and compressive strength of mortar with 100% mineral admixture (lithium slag, fly ash and steel slag) were higher than pure cement mortar, it was about 37.77%/51.88%, 14.71%/11.70%, 14.71%/34.88%, respectively, But the flexural strength and compressive strength reached the maximum when the dosage of mineral admixtures was different. Therefore, mineral admixtures as fine aggregate of mortar were feasible, which can greatly improve the use of industrial waste in the concrete industry, and can achieve the result of energy conservation and emissions reduction.