钢渣的膨胀性抑制方法及其路基填料路用性能的研究

发布时间：2018-01-19 13:38

本文关键词： 矿物材料钢渣膨胀性抑制方法路基填筑材料路用性能　出处：《南京林业大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着钢铁工业的发展，钢渣的排放量逐年扩大。多年来对钢渣作为道路工程材料的研究和应用表明，钢渣的膨胀性是影响其大规模应用的主要因素。开展钢渣膨胀性抑制方法的深入研究符合工程实际的迫切要求，有重要的学术意义和工程实际意义。本文研究了常温浸水处理、单掺矿物材料和复掺矿物材料三种处理方法对钢渣体积膨胀性的抑制效果，并通过XRD物相分析和游离CaO含量测定来分析矿物材料抑制钢渣膨胀性的机理，，在此基础上对钢渣混合料的加州承载比、回弹模量和无侧限抗压强度等基本路用性能进行了研究，得出如下主要结论：（1）对钢渣采取常温浸水处理的措施可以降低钢渣的体积膨胀，但是浸水处理过以后，钢渣混合料试件的强度极低，试件的完好性差。钢渣中掺入矿物材料可以抑制钢渣的膨胀性，同时提高了试件的完好性和抗压强度。（2）单掺矿物材料时,钢渣混合料的膨胀率均随掺量的增加而减小，相同掺量时，硅灰的改善效果好于矿渣微粉，矿渣微粉的改善效果好于粉煤灰。复掺矿物材料时，矿物材料的掺量对钢渣体积稳定性的影响要比矿物材料的种类和配比的影响大。复掺矿渣微粉、粉煤灰与硅灰，掺量为10%，配比分别为1:1:2、1:2:1与2:1:1时，对钢渣的膨胀性有较好的抑制效果。（3）XRD物相分析及游离CaO含量测定结果表明，矿物材料掺入钢渣中不仅降低了游离CaO含量，还生成了可以增加钢渣混合料强度的硅酸盐类产物。随着矿物材料掺量增大，C3S、C2S特征峰增多，游离CaO特征峰减少，峰强度降低，直至消失，并有C3MS2钙镁尖晶石、铁酸钙和钙铝尖晶石C2AS等可以增加钢渣混合料强度的钙硅质盐类产物生成。（4）钢渣中掺入矿物材料可以提高钢渣混合料的CBR值和水稳定性，随着压实度和龄期增大，CBR值增大，水稳定性良好。随着压实度的增加，钢渣混合料的回弹模量增加，矿物材料的掺入增强了钢渣混合料的抗变形能力；养护龄期为28天时，钢渣混合料的回弹模量均在2000MPa以上，且增长幅度较大。（5）掺入矿物材料可以提高钢渣混合料的无侧限抗压强度，含水率为最佳含水率时，复掺矿物材料（矿渣微粉、粉煤灰和硅灰比例为1:1:2，掺量为10%）可以显著提高钢渣混合料的抗压强度。
[Abstract]:With the development of iron and steel industry, the discharge of steel slag is increasing year by year. The intumescence of steel slag is the main factor affecting its large-scale application, and it is of great academic and practical significance to carry out the in-depth research on the inhibition method of steel slag expansion in accordance with the urgent requirements of engineering practice. In this paper, the effects of three treatments, I. e., immersion treatment at room temperature, single mineral material and mixed mineral material, on the volume expansion of steel slag were studied. The mechanism of inhibiting the expansion of steel slag by mineral materials was analyzed by XRD phase analysis and free CaO content measurement, and the California bearing ratio of steel slag mixture was also analyzed. The basic road performance, such as springback modulus and unconfined compressive strength, are studied. The main conclusions are as follows: 1) the volume expansion of steel slag can be reduced by soaking steel slag at room temperature, but the strength of steel slag mixture is very low after soaking treatment. The addition of mineral material into steel slag can inhibit the expansion of steel slag and improve the integrity and compressive strength of the specimen. The expansion ratio of steel slag mixture decreases with the increase of the content of steel slag, and the improvement effect of silica fume is better than that of slag powder. The improvement effect of slag powder is better than that of fly ash. When the mineral material is mixed with mineral material, the effect of mineral material content on the volume stability of steel slag is greater than that of mineral material type and ratio. When the fly ash and silica fume are 10%, the ratio of fly ash and silica fume is 1: 1: 2: 1 and 2: 1: 1, respectively, the expansion of steel slag can be inhibited better by fly ash and silica fume with the ratio of 1: 1: 2: 1 and 1: 1: 1, respectively. The results of phase analysis and free CaO content determination showed that the addition of mineral materials into steel slag not only reduced the content of free CaO. The silicate products can increase the strength of steel slag mixture. With the increase of mineral material content, the characteristic peak of C _ 3SN _ 2S increases, the characteristic peak of free CaO decreases, and the peak strength decreases until it disappears. C3MS2 calcium and magnesium spinel, calcium ferrate and calcium aluminum spinel C2AS can increase the strength of steel slag mixture calcium siliceous salt formation. (4) the addition of mineral material into steel slag can improve the CBR value and water stability of steel slag mixture. With the increase of compaction degree and age, the water stability is good, and with the increase of compaction degree. The elastic modulus of steel slag mixture is increased, and the deformation resistance of steel slag mixture is enhanced by the addition of mineral material. When the curing age is 28 days, the elastic modulus of steel slag mixture is above 2000MPa, and the increase range is larger. The unconfined compressive strength of steel slag mixture can be improved by adding mineral material. When water content is the best, the ratio of mineral material (slag powder, fly ash to silica fume) is 1: 1: 2. The compressive strength of steel slag mixture can be improved significantly.
【学位授予单位】：南京林业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U414

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