Crack Opening Behavior of Concrete Reinforced with High Strength Reinforcing Steel

International Journal of Concrete Structures and Materials

Table 1 Direct tension analysis results (1 MPa = 145.03 Psi; 1 mm = 0.03937 in.).

Bar size material properties	R–O parameters	ρ	Initial crack series		Second crack series		Third crack series
Bar size material properties	R–O parameters	ρ	f_s (MPa)	s (mm)	f_s (MPa)	s (mm)	f_s (MPa)	s (mm)
#4 f_u = 1,200 MPa f_y = 965 MPa	A = 0.004 B = 1,186 C = 2.8	0.02	207	159	227	79	nac
		0.015	262	159	289	79	nac
		0.01	386	318	469	159	nac
		0.0075	503	318	613	159	nac
		0.005	737	635	923	318	nac
		0.0035	1,034	635	nac
#6 f_u = 1,110 MPa f_y = 841 MPa	A = 0.0203 B = 1,365 C = 2.4	0.02	207	159	nac
		0.015	262	318	310	159	nac
		0.01	386	318	441	159	nac
		0.0075	503	635	620	318	nac
		0.005	730	635	910	318	nac
		0.0035	1,027	1,270	nac
#8 f_u = 1,069 MPa f_y = 820 MPa	A = 0.0554 B = 1,550 C = 2.9	0.02	207	318	227	159	nac
		0.015	262	318	289	159	nac
		0.01	379	635	462	318	nac
		0.0075	496	635	613	318	nac
		0.005	730	1,270	916	635	nac
		0.0035	1,027	1,270	nac
#10 f_u = 1,069 MPa f_y = 820 MPa	A = 0.0554 B = 1,551 C = 2.9	0.02	207	318	227	159	nac
		0.015	262	318	289	159	nac
		0.01	379	635	462	318	nac
		0.0075	496	635	565	635	586	318
		0.005	730	1,270	923	635	nac
		0.0035	1,027	2,540	nac

f_y is the 0.2 % offset strain (ASTM 1035), f_s is the stress level at the crack appearance and s is the crack spacing.
nac no additional cracks.