Research on microstructure properties of clay-sand mixtures studied by ipp and mip methods

The clay-sand mixtures with diferent partcle sizes were prepared to investgate partcle and pore characteristcs. The microstructure characteristcs of the sand-clay mixtures were studied by the Mercury Intrusion Porosimetry (MIP) test and Scanning Electron Microscopy (SEM). Image-Pro Plus (IPP) image processing sofware was used to quantfy SEM images which investgated the micro-mechanism of structural evoluton of mixtures under diferent gradatons. The research results indicate that the units of mixtures develop from platelets and honeycomb to agglomerated and granular with the increase of sand content. The contact between partcles transits from face-face contacts to edge-face and pointface contacts. This artcle evaluated the fractal characteristc of partcle and pore structure based on the fractal theory. With the increase Circularity of the partcles, the ordered arrangement of the partcles in the mixed soil is further reduced. In general, the distributon of pores changes from intergranular pores to pores in aggregate, which provides a theoretcal basis for further study on the micro-macro correlaton of mixtures.