Feasibility of a Polymer Foaming Agent as a Grouting Material for Broken Coal Masses

Table 2

Main performance parameters of different materials.

Material	Material-water ratio	Apparent viscosity (MPa·s)	Gel time (h)	Volumetric change
SC	1 : 1.0	337	8.97	Shrinking rate of 23.7%
PF	1 : 1.0	81	0.67	Expansion rate of 9.29%