低活性粉煤灰污染物路用材料的性能评价

Performance Evaluation of Low-activity Flyash as Road Material

基于弹塑性力学和有限元的基本思想,分析了粗颗粒粉煤灰路堤在交通循环荷载作用下的累计塑性变形发展的一般规律;同时采用室内试验与试验路场地验证的方法,对3种能够最大程度上利用细颗粒粉煤灰的基层混合料(灰土稳定粉煤灰、二灰、二灰土)进行了全面路用性能评价。分析结果表明:交通重复荷载下粗颗粒粉煤灰路堤累计塑性变形量明显小于一般性粘土路堤,从而有效地减少了路堤工后不均匀沉降对上部路面结构的影响;细颗粒低活性粉煤灰在水泥早强剂激发下形成的灰土稳定粉煤灰基层材料,不仅体现了良好的室内强度特性,同时在试验路路况评定中也表现了比二灰、二灰土基层试验段良好的路用性能。研究成果为低活性粉煤灰的整治利用提供了方向,并为在公路工程中的推广应用提供了充分的理论依据和技术支持。

First, based on the elastic-plastic theory and FEM method, the cumulative plastic deformation of road embankment of coarse particle low-activity flyash was analyzed. Second, pavement performance of the three kinds of fine particle low-activity flyash mixtures （lime soil stabilizing flyash material, lime-flyash material, lime-flyash soil material） was studied by the laboratory performance evaluation and field validation. The analysis results demonstrate that （1） owing to traffic repeat loading, the cumulative plastic deformation of coarse particle low-activity flyash embankment is less than that of normal clay embankment, which reduce the effect of non- even permanent deformation on pavement performance; （2） base course mixture materials of lime soil stabilizing flyash activated by cement exhibits more excellent performance compared with lime-flyash and lime-flyash soil material. The research findings provide a theoretical and technical support to low activity flyash used in the highway engineering.