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

Table 6

Analysis of variance (slump).

Factors	Square of deviance	Degree of freedom	Mean square	F	F critical value	Significant
Water-cement ratio	98.136	2	49.068	1.953	3.46	No
Volume rate of sand	60.909	2	30.455	1.212	3.46	No
Content of fly ash	13.262	2	6.631	0.264	3.46	No
Silica fume dosages	76.596	2	37.798	1.524	3.46	No
Summation	248.90	8