室内加固的吹填土微结构试验研究

Microstructure experimental investigation of the indoorreinforced dredger fill

在室内进行吹填土加固试验中,在吹填泥浆中分别掺入水泥和石灰两种外掺剂对吹填土进行加固,针对加固后的代表性吹填土样,利用扫描电子显微镜及图像处理技术对其进行微观结构测试。由微观结构照片可以看出,水泥处理后吹填土主要为团—絮状结构,而石灰处理后吹填土主要为团聚状结构。结构单元体的量化分析表明,生石灰处理后土样结构单元体等效直径较大,两种外掺剂处理后的吹填土中颗粒均以扁圆形颗粒为主,加压前土样结构单元体无明显定向性,而在受压后,土样定向性有所增强。孔隙定量化分析显示,压力作用下土体孔隙直径变小,受压前孔隙多为扁圆形,而受压后等轴孔隙数量增多,且受压前后土样孔隙均无明显的择优取向特征。

Cement and calcined lime was incorporated into the dredger fill mud fluid respectively in the indoor reinforcement test. Microstructure of the representative dredger fill samples reinforced by cement and calcined lime was measured by scanning electronic microscope and image processing techniques. Microstructure photo indicates that the samples treated by cement were crumb-flocculent structure while the samples treated by calcined lime were aggregate structure. According to the quantitative analysis of unit body of structure, equivalent diameter of the samples treated by calcined lime is larger and the grain of treated samples is mainly oblate. Directional property of unit body of structure before compression is weak, while that after compression becomes apparent. According to the quantitative analysis of pore, diameter of the pore becomes smaller under compression. The pore is mainly oblate before compression and equiaxed pore increases after compression. The pore has no apparent directional property.