入掺偏高岭土的钢渣活性激发机理与固化软粘土效能

The steel slag, a kind of industrial wastes, is difficult to be refined to recycling for it is relatively inert and of the active and expansive calcium oxide, which leads to the land occupation and environment pollution. The activity of the steel slag powder mixed with the metakaolin was chemically excited firstly to form the slag-based composite reinforcement material, and then it was used to solidify the soft clays and realizes the efficient reuse of the waste resources. To arrive this objective, the clinker rate in cement industry was introduced to determine the ratio of the slag to metakaolin, and then it was excited by the materials e.g. lime, cement, sodium silicate and sodium hydroxide. During this period, the strength, composition and morphology of the slag paste were tracked and the reasonable slag-based composite material was formed. Thereafter, the soft clay was solidified with the material, where the mechanism of the strength evolution was focused, and the reaction of the ion exchange, the aggregation and coagulation between the hydration products and clay particles was clarified by the combined microscopic testing methods. At the end of this research, the phase (or the composition) and the pH value of the excitation environment were adjusted, and the solidification of the soft clay was re-conducted again. The mechanism of the each phase of the slag-based composite to synergistically improve the soft clays could be achieved and then the ratio of the composite can also be optimized. Above all, the results will be of the social significance in the efficient use of waste resources and environment protection, and of the important scientific value in the development of the new inorganic cementitious materials and, deepening the cognition of the strength formation mechanism in the soft clay stabilization.

本研究以粉粒状钢渣这一相对惰性且含有活性膨胀性氧化钙的工业废弃物为研究对象，通过入掺偏高岭土和化学活性激发技术，形成钢渣型复合基材，将其用于固化软粘土，实现废弃物资源化高效利用的目标。研究首先引入水泥率值参数，确定钢渣与偏高岭土的比例，采用石灰、水泥、水玻璃和氢氧化钠等材料进行激发，跟踪净浆的强度、胶结产物的成分与形态演化规律，获得钢渣型复合基材；开展复合基材加固软粘土的试验，明确固化宏观效果，结合微观测试手段，探究复合基材水化产物与粘土颗粒间的离子交换、团粒化以及硬凝反应机理；调整基材的各相比例以及激发环境的pH值等参数，再次开展固化软粘土试验，揭示复合基材各相协同固化软粘土的作用机制，提出复合基材配比的优化技术。研究成果在废弃物资源化利用方面具有社会意义和环保效益，对新型无机胶凝性固化软粘土材料的研发、加深固化软粘土强度形成机制的认知具有重要的科学价值。

本研究以粉粒状钢渣这一相对惰性且含有活性膨胀性氧化钙的工业废弃物为研究对象，通过入掺偏高岭土和化学活性激发技术，形成钢渣型复合基材，将其用于固化软粘土，实现废弃物资源化高效利用的目标。研究首先引入水泥率值参数，确定钢渣与偏高岭土的比例，采用石灰、水泥、水玻璃和氢氧化钠等材料进行激发，跟踪净浆的强度、胶结产物的成分与形态演化规律，获得钢渣型复合基材；开展复合基材加固软粘土的试验，明确固化宏观效果，结合微观测试手段，探究复合基材水化产物与粘土颗粒间的离子交换、团粒化以及硬凝反应机理；调整基材的各相比例以及激发环境的pH值等参数，再次开展固化软粘土试验，揭示复合基材各相协同固化软粘土的作用机制，提出复合基材配比的优化技术。研究成果在废弃物资源化利用方面具有社会意义和环保效益，对新型无机胶凝性固化软粘土材料的研发、加深固化软粘土强度形成机制的认知具有重要的科学价值。