Response Surfaces for Fresh and Hardened Properties of Concrete with E-Waste (HIPS)

Table 11

Analysis of variance for 28-day compressive strength (MPa) response surface quadratic model.

Source	Sum of squares	Degrees of freedom	Mean square	value	value
Model	839.64	5	167.93	49.36	<0.0001
-HIPS (Vol %)	400.00	1	400.00	117.57	<0.0001
- ratio	429.77	1	429.77	126.32	<0.0001
	7.13	1	7.13	2.10	0.1910
	0.71	1	0.71	0.21	0.6625
	1.00	1	1.00	0.29	0.6051
Residual	23.81	7	3.40
Lack of fit	23.81	3	7.94
Pure error	0.000	4	0.000
Total	863.45	12