Optimal Proportion of Similar Materials and Rockburst Tendency of White Sandstone

Table 5

Analysis of the extreme difference in compressive strength of each factor covered by the study.

Factor level	(A) Quartz sand (%)	(B) Iron powder (%)	(C) Plaster : cement	(D) Sand size (mm)
I1	12.64	11.37	10.71	11.38
I2	11.52	11.16	11.42	12.18
I3	11.40	11.59	11.85	12.23
I4	10.49	9.92	12.07	10.26
Range	2.15	1.67	1.35	1.98