固化污泥的压实特性及微观机理研究

固化污泥进入填埋场需要压实,为探求一种经济有效的方法将其填埋,需要对压实过程中微观结构特征的变化进行研究,揭示污泥固化土的压实机理。对以水泥为固化材料的污泥进行击实试验,通过真空冷冻干燥技术制样,进行扫描电镜试验;借助GIS技术实现了SEM图像的三维可视化及三维孔隙率的定量计算,分析击实过程中微观孔隙的变化规律。结果表明,固化污泥的干密度随着击实功的增加先增加后趋于稳定、孔隙率先减小后趋于稳定。三维可视化模型实现了土体颗粒表面起伏形态的三维显示。对比结果显示三维孔隙率的变化情况,较好地描述了固化污泥击实过程中孔隙体积的变化,可以依据三维孔隙率的变化选取一个经济击实功。研究成果为污泥固化土这种特殊性质土体的基本力学性质研究提供基础参数,并为其实际填埋施工工艺选择提供理论依据。

Study on compaction characteristics and micromechanism of solidified sludge

: Solidified sludge need compacted in landfill disposal, in order to find a cost-effective method to landfill, need to conduct research of the changes of microstructure in the compaction process, reveals the compaction mechanism of solidified sludge. The studies which conducted by compaction test of landfill disposal, sample preparation by vacuum freeze-drying technology, carry on SEM test. The GIS technology is used to realize Three-dimensional visualization of the image of SEM and to calculate three-dimensional porosity, analysis the variation of microcosmic pores in the compaction process. The results show that with the increase of compaction work, the dry density of solidified sludge increases firstly and then tend to stabilize, the porosity reduces firstly and then tend to stabilize. The 3D visualization model realize 3D display of the surface of soil particles. Comparative results show that the changes of 3D porosity describe the changes in pore volume well in the process of compaction, can select an economy compaction work based on the changes of 3D porosity. Research results provide basis parameters for studies on basic mechanical properties of solidified sludge, this special nature of the soil, and provide a theoretical basis for the selection of construction crafts in the actual landfill.