Steel Fibre Reinforcing Characteristics on the Size Reduction of Fly Ash Based Concrete

Table 5

Flexural strength for various mixture proportions of concrete.

Mix Id	w/b ratio	F/c ratio	Fly ash (%)	GSF (%)	Acl (%)	PCE (%)	Depth of prism (mm)	Flexural strength at 7 days (MPa)	% of strength gain at 7 days	Flexural strength at 28 days (MPa)	% of strength gain at 28 days
MC1	0.3	0.6	0	0	0	1.5	100	4.28	—	5.63	—
MSF1	0.3	0.6	25	0.5	1	1.5	100	4.32	0.98	5.89	4.60
							95	4.10	−4.21	5.57	−1.07
							90	3.85	−10.05	5.30	−5.86
							85	3.50	−18.22	4.85	−13.85
MSF2	0.3	0.6	25	1.0	1	1.5	100	4.36	1.89	5.89	6.07
							95	4.25	−0.70	5.74	1.95
							90	4.25	−0.70	5.65	0.36
							85	3.75	−12.38	5.30	−5.86
MSF3	0.3	0.6	25	1.5	1	1.5	100	4.65	8.64	6.70	25.00
							95	4.50	5.14	6.45	14.56
							90	4.70	9.81	6.69	18.83
							85	4.30	0.47	5.95	−3.20
MSF7	0.3	0.6	50	0.5	1	1.5	100	3.83	−10.51	5.14	−8.70
							95	3.75	−12.38	5.05	−10.30
							90	3.56	−16.82	4.02	−28.60
							85	3.20	−25.23	3.65	−35.17
MSF8	0.3	0.6	50	1.0	1	1.5	100	3.43	−19.86	5.73	1.78
							95	3.98	−7.01	5.65	0.36
							90	3.75	−12.38	4.39	−22.02
							85	3.41	−20.33	3.12	−44.58
MSF9	0.3	0.6	50	1.5	1	1.5	100	4.13	−3.50	6.16	9.41
							95	4.05	−5.37	6.08	7.99
							90	3.98	−1.87	5.39	−4.26
							85	3.26	−7.00	5.25	−6.75

Note: w/b: water to binder ratio; F/c: fine to coarse aggregate ratio; GSF: glued steel fibres; Acl: accelerator; PCE: polycarboxylic ether based superplasticizer; +ve sign indicates the increasing trend and −ve sign indicates the decreasing trend.