Experimental Study on Compression Characteristics of Gangue Grouting Filling Materials: Fid-Bau Portal

Experimental Study on Compression Characteristics of Gangue Grouting Filling Materials

Wu, Jiang / Chen, Bing / Chai, Shunjie / Kong, Wenlei

Abstract In order to study the compression deformation characteristics of filling materials with gangue grouting, the compression test device for filling material with gangue grouting was made, and contrastive compression tests were carried out for different sizes filling materials with non-grouting of gangue and gangue grouting. Compared with the filling material with gangue non-grouting, the results showed that the axial strain-axial stress curves of filling material of gangue grouting was smoother, the slope decreased, the elastic modulus increased, compressibility reduced and the compression deformation decreased. During the compression process, the axial strain increasing rate of filling material of gangue with non-grouting and grouting gradually decreased with the increasing stress, and they can be divided into three stages, respectively, and the three stages was named speed compaction stage, stabilization compaction stage and steady compaction stage, respectively. In the steady compaction stage, when the axial stress applied to the filling material with gangue grouting is 11.5 MPa, as the diameter of gangue particles increased from 0 ~ 20 to 0 ~ 40 mm, the axial strain amplitude greatly, but when gangue particles increased from 0 ~ 40 to 0 ~ 50 mm, the amplification of axial strain decreased. When the gangue particles increased from 0 ~ 50 to 0 ~ 60 mm, the axial strain increased only by 0.009. Small particles gangue was mostly located at the bottom of filling materials, when the proportion was large, the filling effect and gangue cementation effect of the slurry in the gangue gap were affected. Considering comprehensively, the optimal particles of filling materials with gangue grouting selected in this paper was 0 ~ 40 mm. The results of this study are of guiding significance for the reasonable selection of filling materials with gangue particles to control surface deformation.