Mechanical Properties of Tunnel Muck with Fly-Ash Geopolymer

Figure 8

Different scale of SEM images of geopolymer sample: (a) the soil particle and fly ashes are strengthened by flocculence; (b) 10-time zoomed out view of (a); (c) the materials that were not involved in the chemical reaction, which are filler and skeleton of geopolymer sample; (d) typical fly ash particle after the reaction with structural holes on the surface.