Application of High-Strength Lightweight Concrete in Gob-Side Entry Retaining in Inclined Coal Seam

Table 5

Analysis of variance (slump).

Factors	Square of deviance	Degree of freedom	Mean square	F	F critical value	Significant
Water-cement ratio	637.556	2	336.778	0.948	6.94	No
Volume rate of sand	6000.222	2	3000.111	8.448	6.94	Yes
Content of fly ash	746.889	2	373.445	1.052	6.94	No
Silica fume dosages	12355.56	2	6177.778	17.397	6.94	Yes
Summation	19776.22	8