Investigation and practical application of a new cementitious anti-washout grouting material

The inrush water disaster seriously affects the construction of tunnel and underground engineering. In order to improve the efficiency of dynamic groundwater sealing in karst area, a new cementitious anti-washout grouting material (CIS) was prepared which consist of matrix material ordinary Portland cement, coagulant accelerator water glass and flocculating agent xanthan gum. The results show that CIS grout has the advantages of short setting time, high early mechanical strength, high slurry viscosity, high slurry retention rate and non-toxic, and it has the advantages over the cement-water glass slurry which is most widely used in the dynamic groundwater sealing engineering. The mechanism effect of water glass and xanthan gum on the workability of CIS grout was discussed by hardening process, X-Ray Diffraction (XRD), Mercury Intrusion Porosimetry (MIP), Infrared spectrum (IR) and Scanning Electron Microscope (SEM). A design method of grouting parameters was proposed based on the setting time and viscosity evolution, and the contrast application of CIS grout with cement-water glass grout was carried out in water inrush control project of limestone mine in Karst Area, and the water rushing was treated more effectively by CIS grout.