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Code Related Data

Codes with strength reduction factors

Codes with partial safety factors on materials

Current tabular codes

Codes with resistance factor on materials

Superseeded codes with partial safety factors on materials

American Codes

These codes use strength reduction factors.

ACI318-08ACI318-11ACI318-14
Concrete strength fc{f'}_c fc{f'}_c fc{f'}_c
Steel strength fyf_{y} fyf_{y} fyf_{y}
Strength reduction factor for axial compression*  fc{f}_cf = 0.65
[9.3.2.2]
f = 0.65
[9.3.2.2]
f = 0.65
[21.2.2]
Strength reduction factor for axial tension*  fs{f}_sf = 0.9
[9.3.2.1]
f = 0.9
[9.3.2.1]
f = 0.9
[21.2.2]
Uncracked concrete design strength for rectangular stress block  fcdu{f}_{cdu}0.85  fc{f'}_c
[10.2.7.1]

0.85  fc{f'}_c
[10.2.7.1]

0.85  fc{f'}_c
[22.2.2.4.1]

Cracked concrete design strength (equal to twice the upper limit on shear strength) fcdc{f}_{cdc}(5/3) fc\sqrt{{f'}_c}  ( fc{f'}_c  in MPa)
20 fc\sqrt{{f'}_c}    ( fc{f'}_c  in psi)
[11.2.1.1 & 11.4.7.9]
1.66 fc\sqrt{{f'}_c}   ( fc{f'}_c  in MPa)
20 fc\sqrt{{f'}_c}    (  fc{f'}_c  in psi)
[11.2.1.1 & 11.4.7.9
11.9.3]
1.66 fc\sqrt{{f'}_c}  ( fc{f'}_c  in MPa)
20 fc\sqrt{{f'}_c}      (  fc{f'}_c  in psi)
[11.5.4.3]
Concrete tensile design strength (used only to determine whether section cracked) fcdt{f}_{cdt}(1/3) fc\sqrt{{f'}_c}  ( fc{f'}_c  in MPa)
4 fc\sqrt{{f'}_c}      ( fc{f'}_c  in psi)
[11.3.3.2]
0.33 fc\sqrt{{f'}_c}   ( fc{f'}_c  in MPa)
4 fc\sqrt{{f'}_c}      ( fc{f'}_c  in psi)
[11.3.3.2]
0.33 fc\sqrt{{f'}_c}  ( fc{f'}_c  in MPa)
4 fc\sqrt{{f'}_c}     ( fc{f'}_c  in psi)
[22.5.8.3.3]
Compressive plateau concrete strain ϵctrans{\epsilon}_{ctrans}0.002
[assumed]
0.002
[assumed]
0.002
[assumed]
Maximum axial compressive concrete strain ϵcax{\epsilon}_{cax}0.003
[10.2.3]
0.003
[10.2.3]
0.003
[22.2.2.1]
Maximum flexural compressive concrete strain ϵcu{\epsilon}_{cu}0.003
[10.2.3]
0.003
[10.2.3]
0.003
[22.2.2.1]
Proportion of depth to neutral axis over which constant stress acts β\beta0.85-0.05( fc{f'}_c -30)/7
( fc{f'}_c  in MPa)
0.85- 0.05( fc{f'}_c /1000-4)
( fc{f'}_c  in psi)
but within limits 0.65 to 0.85
[10.2.7.3]
β1\beta_1
0.85-0.05( fc{f'}_c -28)/7
( fc{f'}_c  in MPa)
0.85- 0.05( fc{f'}_c /1000-4)
( fc{f'}_c  in psi)
but within limits 0.65 to 0.85
[10.2.7.3]
β1\beta_1
0.85-0.05( fc{f'}_c -28)/7
( fc{f'}_c  in MPa)
0.85- 0.05( fc{f'}_c /1000-4)
( fc{f'}_c  in psi)
but within limits 0.65 to 0.85
[22.2.2.4.3]
β1\beta_1
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations  (xd)max{(\frac{x}{d})}_{max}11+0.004ϵcu\frac{1}{1 + \frac{0.004}{\epsilon_{cu}}}
[10.3.5]
cdmax{\frac{c}{d}}_{max}
11+0.004ϵcu\frac{1}{1 + \frac{0.004}{\epsilon_{cu}}}
[10.3.5]
cdmax{\frac{c}{d}}_{max}
11+0.004ϵcu\frac{1}{1 + \frac{0.004}{\epsilon_{cu}}}
[7.3.3.1 & 8.3.3.1]
cdmax{\frac{c}{d}}_{max}
Elastic modulus of steel EsE_s200 GPa
[8.5.2]
200 GPa
[8.5.2]
200 GPa
[20.2.2.2]
Design strength of reinforcement in tension  fydf_{yd} fyf_{y}
[10.2.4]
 fyf_{y}
[10.2.4]
 fyf_{y}
[20.2.2.1]
Design strength of reinforcement in compression  fydcf_{ydc} fyf_{y}
[10.2.4]
 fyf_{y}
[10.2.4]
 fyf_{y}
[20.2.2.1]
Maximum linear steel stress  flimf_{lim} fyf_{y}
[10.2.4]
 fyf_{y}
[10.2.4]
 fyf_{y}
[20.2.2.1]
Yield strain in tension ϵplas{\epsilon}_{plas} fyf_{y} / EsE_s
[10.2.4]
 fyf_{y} / EsE_s
[10.2.4]
 fyf_{y} / EsE_s
[20.2.2.1]
Yield strain in compression ϵplasc{\epsilon}_{plasc} fyf_{y} / EsE_s
[10.2.4]
 fyf_{y} / EsE_s
[10.2.4]
 fyf_{y} / EsE_s
[20.2.2.1]
Design strain limit ϵsll{\epsilon}_{sll}[0.01]
assumed
[0.01]
assumed
[0.01]
assumed
Maximum concrete strength---
Maximum steel strength-
-
-
Minimum eccentricity0.10 h
[R10.3.6 & R10.3.7]
0.10 h
[R10.3.6 & R10.3.7]
0.10 h
[R22.4.2.1]
Minimum area compression reinforcement-

-

-

maximum permitted angle between applied and resulting principal stress φΔ{\varphi}_{\Delta}---

*Applied forces and moments are divided by the strength reduction factor to obtain design values for use within RCSlab. The appropriate vales are determined as follows:

M=abs(Mxx+Myy)2+MxxMyy24+Mxy2M = \frac{abs(M_{xx} + M_{yy})}{2} + \sqrt{\frac{{M_{xx} - M_{yy}}^2}{4} + {M_{xy}}^2}
N=Nxx+Nyy2+NxxNyy24+Nxy2N = \frac{N_{xx} + N_{yy}}{2} + \sqrt{\frac{{N_{xx} - N_{yy}}^2}{4} + {N_{xy}}^2}
zmin=min(zt1,zt2,zb1,zb2)z_{min} = \min{(z_{t1}, z_{t2}, -z_{b1}, -z_{b2})}

kuc = εcu/(εcu + fyd/Es)

kut = εcu/(εcu + 0.005)

Mc = φckucβfcdc × (1 - kucβ/2) × (h/2 + zmin)2 - N × zmin

Mt = φtkutβfcdc × (1 - kutβ/2) × (h/2 + zmin)2 - N × zmin

If MMt:ϕ=ϕtM \le M_t : \phi = \phi_{t}

If MMc:ϕ=ϕcM \ge M_c : \phi = \phi_{c}

Otherwise: ϕ=[(McM)ϕt+(MMt)ϕc](McMt)\phi = \frac{\left\lbrack \left( M_{c} - M \right)\phi_{t} + \left( M - M_{t} \right)\phi_{c} \right\rbrack}{\left( M_{c} - M_{t} \right)}

Australian Codes

This code uses strength reduction factors.

AS3600
Concrete strength fc{f'}_c
Steel strength fsyf_{sy}
Strength reduction factor for axial compression*  fc{f}_cf = 0.6
[Table 2.2.2]
Strength reduction factor for axial tension*  fs{f}_sf = 0.8     (N bars)
f = 0.64   (L bars)
[Table 2.2.2]
Uncracked concrete design strength for rectangular stress block  fcdu{f}_{cdu} α2\alpha_2 fc{f'}_c
Where  α2\alpha_2= 1.00-0.003  fc{f'}_c
but within limits 0.67 to 0.85
[10.6.2.5(b)]
Cracked concrete design strength (equal to twice the upper limit on shear strength) fcdc{f}_{cdc}0.4  fc{f'}_c
[11.6.2]

Concrete tensile design strength (used only to determine whether section cracked) fcdt{f}_{cdt}0.36 fc\sqrt{{f'}_c}
[3.1.1.3]
Compressive plateau concrete strain ϵctrans{\epsilon}_{ctrans}0.002
[assumed]
Maximum axial compressive concrete strain ϵcax{\epsilon}_{cax}0.0025
[10.6.2.2(b)]
Maximum flexural compressive concrete strain ϵcu{\epsilon}_{cu}0.003
[8.1.2.(d)]
Proportion of depth to neutral axis over which constant stress acts β\beta1.05-0.007  fc{f'}_c
but within limits 0.67 to 0.85
[10.6.2.5(b)]
γ\gamma


Maximum value of ratio of depth to neutral axis to effective depth in flexural situations  (xd)max{(\frac{x}{d})}_{max}0.36
[8.1.5]
ku,maxk_{u,max}
Elastic modulus of steel EsE_s200 GPa
[3.2.2(a)]
Design strength of reinforcement in tension  fydf_{yd} fsyf_{sy}
[3.2.1]
Design strength of reinforcement in compression  fydcf_{ydc} fsyf_{sy}
[3.2.1]
Maximum linear steel stress  flimf_{lim} fsyf_{sy}
[3.2.1]
Yield strain in tension ϵplas{\epsilon}_{plas} fsyf_{sy} / EsE_s
[3.2.1]
Yield strain in compression ϵplasc{\epsilon}_{plasc} fsyf_{sy} / EsE_s
[3.2.1]
Design strain limit ϵsll{\epsilon}_{sll}Class N 0.05
Class L 0.015
[3.2.1]
Maximum concrete strength-
Maximum steel strength fsyf_{sy}  £ 500 MPa
[3.2.1]
Minimum eccentricity0.05 h
[10.1.2]
Minimum area compression reinforcement0.01
(0.5% each face)
[10.7.1 (a)]
Maximum permitted angle between applied and resulting principal stress φΔ{\varphi}_{\Delta}-

*Applied forces and moments are divided by the strength reduction factor to obtain design values for use within RCSlab. The appropriate vales are determined as follows:

M=abs(Mxx+Myy)2+MxxMyy24+Mxy2M = \frac{abs(M_{xx} + M_{yy})}{2} + \sqrt{\frac{{M_{xx} - M_{yy}}^2}{4} + {M_{xy}}^2}
N=Nxx+Nyy2+NxxNyy24+Nxy2N = \frac{N_{xx} + N_{yy}}{2} + \sqrt{\frac{{N_{xx} - N_{yy}}^2}{4} + {N_{xy}}^2}
zmin=min(zt1,zt2,zb1,zb2)z_{min} = \min{(z_{t1}, z_{t2}, -z_{b1}, -z_{b2})}

kuc = (1.19 - φc) × 12/13

kut = (1.19 - φt) × 12/13

kub = εcu/(εcu + fyd/Es)

Mc = φckucβfcdc × (1 - kucβ/2) × (h/2 + zmin)2 - min(0, N) × zmin

Mt = φtkutβfcdc × (1 - kutβ/2) × (h/2 + zmin)2 - min(0, N) × zmin

Nb = [φckubβfcdc × (1 - kubβ/2) × (h/2 + zmin)2 - M] / zmin

If MMt:ϕb=ϕtM \le M_t : \phi_{b} = \phi_{t}

If MMc:ϕb=ϕcM \ge M_c : \phi_{b} = \phi_{c}

Otherwise: ϕb=[(McM)ϕt+(MMt)ϕc](McMt)\phi_{b} = \frac{\left\lbrack \left( M_{c} - M \right)\phi_{t} + \left( M - M_{t} \right)\phi_{c} \right\rbrack}{\left( M_{c} - M_{t} \right)}

If N0:ϕ=ϕtN \le 0 : \phi = \phi_{t}

If MNb:ϕ=ϕcM \ge N_b : \phi = \phi_{c}

Otherwise: ϕ=ϕb(1+[14(ϕbϕc)×(NNb)ϕb2])2\phi = \phi_{b}\frac{\left( 1 + \sqrt{\left\lbrack 1 - 4\left( \phi_{b} - \phi_{c} \right) \times \frac{\left( \frac{N}{N_{b}} \right)}{{\phi_{b}}^{2}} \right\rbrack} \right)}{2}

Eurocode

These codes use partial safety factors on materials.

EN1992-1-1 2004 +A1:2014EN1992-2 2005
Concrete strengthfckf_{ck}fckf_{ck}
Steel strengthfykf_{yk}fykf_{yk}
Partial safety factor on concrete γC\gamma_{C} = 1.5
[2.4.2.4(1)]
γC\gamma_{C} = 1.5
[2.4.2.4(1)]
Partial safety factor on steelγS\gamma_{S} = 1.15
[2.4.2.4(1)]
γS\gamma_{S} = 1.15
[2.4.2.4(1)]
Uncracked concrete design strength for rectangular stress block  fcdu{f}_{cdu}fckf_{ck} \le 50 MPa                               αcc\alpha_{cc}fckf_{ck}/γC\gamma_{C} 

fckf_{ck} > 50 MPa            (1 - (fckf_{ck}-50)/200) ×\times
αcc\alpha_{cc}fckf_{ck}/γC\gamma_{C}

αcc\alpha_{cc} is an NDP*
[3.1.7(3)]
ηfcd{\eta}f_{cd}
fckf_{ck} \le 50 MPa                 αcc\alpha_{cc}fckf_{ck}/γC\gamma_{C} 

fckf_{ck} > 50 MPa           (1 - (fckf_{ck}-50)/200)  ×\times
αcc\alpha_{cc}fckf_{ck}/γC\gamma_{C}

αcc\alpha_{cc} is an NDP*
[3.1.7(3)]
ηfcd{\eta}f_{cd}
Cracked concrete design strength (equal to twice the upper limit on shear strength) fcdc{f}_{cdc}0.6×\times(1-fckf_{ck}/250)×\times fckf_{ck}/γC\gamma_{C}  
[6.2.2(6)]  
νfcd{\nu}f_{cd}
0.312×\times(1-fckf_{ck}/250)×\times fckf_{ck}/γC\gamma_{C}  
[6.109 (103)iii]   (see also ϕΔ)  
νfcd{\nu}f_{cd}
Concrete tensile design strength (used only to determine whether section cracked) fcdt{f}_{cdt}fckf_{ck} \le 50 MPa    αct\alpha_{ct} ×\times 0.21 fckf_{ck} 2/3/γC\gamma_{C}  

fckf_{ck} > 50 MPa αct\alpha_{ct} ×\times 1.48 ×\times ln[1.8+ fckf_{ck}/10] /γC\gamma_{C}  
αct\alpha_{ct} is an NDP*  

[Table 3.1]  
fcdtf_{cdt}
fckf_{ck} \le 50 MPa    αct\alpha_{ct} ×\times 0.21 fckf_{ck} 2/3/ γC\gamma_{C}  

fckf_{ck} > 50 MPa αct\alpha_{ct} ×\times 1.48 ×\times ln[1.8+ fckf_{ck}/10] /γC\gamma_{C}  
αct\alpha_{ct} is an NDP* 

[Table 3.1]  
fcdtf_{cdt}
Compressive plateau concrete strain ϵctrans{\epsilon}_{ctrans}fckf_{ck} \le 50 MPa 0.00175  

fckf_{ck} > 50 MPa 0.00175+ 0.00055 ×\times [(fckf_{ck}-50)/40]  

[Table 3.1]  
ϵc3\epsilon_{c3}
fckf_{ck} \le 50 MPa 0.00175  

fckf_{ck} > 50 MPa 0.00175+ 0.00055 ×\times [(fckf_{ck}-50)/40]  

[Table 3.1]  
ϵc3\epsilon_{c3}
Maximum axial compressive concrete strain ϵcax{\epsilon}_{cax}fckf_{ck} \le 50 MPa 0.00175  

fckf_{ck} > 50 MPa 0.00175+ 0.00055 ×\times [(fckf_{ck}-50)/40]  
[Table 3.1]  
ϵc3\epsilon_{c3}
fckf_{ck} \le 50 MPa 0.00175  
fckf_{ck} > 50 MPa 0.00175+ 0.00055 ×\times [(fckf_{ck}-50)/40]  
[Table 3.1]  
ϵc3\epsilon_{c3}
Maximum flexural compressive concrete strain ϵcu{\epsilon}_{cu}fckf_{ck} \le 50 MPa 0.0035  

fckf_{ck} > 50 MPa 0.0026+0.035 ×\times [(90-fckf_{ck})/ 100]4  

[Table 3.1]  
ϵcu3\epsilon_{cu3}
fckf_{ck} \le 50 MPa 0.0035  

fckf_{ck} > 50 MPa 0.0026+0.035 ×\times [(90-fckf_{ck})/ 100]4  

[Table 3.1]  
ϵcu3\epsilon_{cu3}
Proportion of depth to neutral axis over which constant stress acts β\betafckf_{ck} \le 50 MPa        0.8  

fckf_{ck} > 50 MPa                   0.8-(fckf_{ck}-50)/400  

[3.1.7(3)]  
λ\lambda
fckf_{ck} \le 50 MPa        0.8  

fckf_{ck} > 50 MPa                   0.8-(fckf_{ck}-50)/400  

[3.1.7(3)]   λ\lambda
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations  xdmax{\frac{x}{d}}_{max}fckf_{ck} \le 50 MPa              (1- k1k_1 )/ k2k_2    

fckf_{ck} > 50 MPa              (1- k3k_3 )/ k4k_4    

k1k_1k2k_2k3k_3  and   k4k_4  are NDPs*    
[5.5(4)]
fckf_{ck} \le 50 MPa               (1- k1k_1 )/ k2k_2    

fckf_{ck} > 50 MPa             (1- k3k_3 )/ k4k_4    

k1k_1k2k_2k3k_3  and   k4k_4  are NDPs*    
[5.5(104)]
Elastic modulus of steel EsE_s200 GPa

[3.2.7(4)]

EsE_s
200 GPa

[3.2.7(4)]

EsE_s
Design strength of reinforcement in tension  fydf_{yd} fykf_{yk} / γs\gamma_s
[3.2.7(2)]
fydf_{yd}
 fykf_{yk} / γs\gamma_s
[3.2.7(2)]
fydf_{yd}
Design strength of reinforcement in compression  fydcf_{ydc} fykf_{yk} / γs\gamma_s
[3.2.7(2)]
fydf_{yd}
 fykf_{yk} / γs\gamma_s
[3.2.7(2)]
fydf_{yd}
Maximum linear steel stress  flimf_{lim} fykf_{yk} / γs\gamma_s
[3.2.7(2)]
 fykf_{yk} / γs\gamma_s
[3.2.7(2)]
Yield strain in tension ϵplas{\epsilon}_{plas} fykf_{yk} /( γs\gamma_s  EsE_s )
[3.2.7(2)]
 fykf_{yk} /( γs\gamma_s  EsE_s )
[3.2.7(2)]
Yield strain in compression ϵplasc{\epsilon}_{plasc} fykf_{yk} /( γs\gamma_s  EsE_s )
[3.2.7(2)]
 fykf_{yk} /( γs\gamma_s  EsE_s )
[3.2.7(2)]
Design strain limit ϵsll{\epsilon}_{sll}NDP*
[ϵcl\epsilon_{cl}]

NDP*
[ϵcl\epsilon_{cl}]

Maximum concrete strengthfckf_{ck} \le 90 MPa
[3.1.2(2)]
fckf_{ck} \le 90 MPa
[3.1.2(2)]
Maximum steel strength fykf_{yk}  \le 600 MPa
[3.2.2(3)]
 fykf_{yk}  \le 600 MPa
[3.2.2(3)]
Minimum eccentricitymax{h/30, 20 mm}
[6.1(4)]
max{h/30, 20 mm}
[6.1(4)]
Minimum area compression reinforcement--
Maximum permitted angle between applied and resulting principal stress φΔ{\varphi}_{\Delta}-

θθel\|\theta-\theta_{el}\| = 15°
[6.109 (103)iii]
(see also fcdcf_{cdc})

*NDPs are nationally determined parameters.

Hong Kong Codes

These codes use partial safety factors on materials.

Hong Kong Buildings 2013Hong Kong Structural Design Manual for Highways and Railways 2013
Concrete strengthfcuf_{cu}fck,cubef_{ck,cube}
Steel strengthfyf_{y}fykf_{yk}
Partial safety factor on concrete γmc\gamma_{mc} = 1.5
[Table 2.2]
γc\gamma_c = 1.5
[5.1]
Partial safety factor on steel γms\gamma_{ms} = 1.15
[Table 2.2]
γs\gamma_{s} = 1.15
[5.1]
Uncracked concrete design strength for rectangular stress block  fcdu{f}_{cdu}0.67fcuf_{cu}/γmc\gamma_{mc}
[Figure 6.1]
0.67fck,cubef_{ck,cube} / γC\gamma_{C}
[Figure 5.3]
Cracked concrete design strength (equal to twice the upper limit on shear strength) fcdc{f}_{cdc}min{17.5, 2fcu\sqrt{f_{cu}}} / γmc\gamma_{mc} 0.55  
[6.1.2.5(a)]
0.6 ×\times (1-0.8fck,cubef_{ck,cube} /250) ×\times 0.8fck,cubef_{ck,cube} / γC\gamma_{C}  
[5.1]
Concrete tensile design strength (used only to determine whether section cracked) fcdt{f}_{cdt}0.36fcu\sqrt{f_{cu}}/ γmc\gamma_{mc}  
[12.3.8.4]
fckf_{ck} \le 60 MPa            [0.025fck,cubef_{ck,cube} + 0.6] /γC\gamma_{C}  

fckf_{ck} > 60 MPa     2.1 /γC\gamma_{C}  

[Table 5.1]
Compressive plateau concrete strain ϵctrans{\epsilon}_{ctrans}0.002 
[assumed]
[0.026fck,cubef_{ck,cube} + 1.1] /γC\gamma_{C}  
[5.2.6(1) & Table 5.1]  
ϵc2\epsilon_{c2}
Maximum axial compressive concrete strain ϵcax{\epsilon}_{cax}fcuf_{cu} \le 60 MPa 0.0035  

fcuf_{cu} > 60 MPa 0.0035- 0.00006 ×\times fcu\sqrt{f_{cu}}-60]  
[Figure 6.1]
[0.026fckf_{ck},cube + 1.1] /γC\gamma_{C}  
[5.2.6(1) & Table 5.1]  
ϵc2\epsilon_{c2}
Maximum flexural compressive concrete strain ϵcu{\epsilon}_{cu}fcuf_{cu} \le 60 MPa 0.0035  

fcuf_{cu} > 60 MPa 0.0035- 0.00006 ×\times fcu\sqrt{f_{cu}}-60]  

[Figure 6.1]
fckf_{ck},cube \le 60 MPa 0.0035  

fckf_{ck},cube > 60 MPa 0.0035- 0.00006 ×\times fck,cube\sqrt{f_{ck,cube}}-60]  

[5.2.6(1)]
Proportion of depth to neutral axis over which constant stress acts β\betafcuf_{cu} \le 45 MPa 0.9  

45 < fcuf_{cu} \le 70 0.8  

fcuf_{cu} > 70 MPa 0.72 

[Figure 6.1]
fckf_{ck},cube \le 45 MPa      0.9  

45 < fck,cubef_{ck,cube} \le 70      0.8  

70 < fckf_{ck},cube \le 85     0.72   

[Figure 5.3]
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations  xdmax{\frac{x}{d}}_{max}fcuf_{cu} \le 45 MPa   0.50  

45 < fcuf_{cu} \le 70    0.40  

fcuf_{cu} > 70 MPa   0.33 

[6.1.2.4(b)]
fckf_{ck} \le 50 MPa 0.344  

fckf_{ck} > 50 MPa             0.6/{0.6 + 0.4/ (2.6 + 35[(90-fckf_{ck})/100] 4^4 )}  

[5.1]
Elastic modulus of steel EsE_s200 GPa
[Figure 3.9]
200 GPa
[5.1]
EsE_s
Design strength of reinforcement in tension  fydf_{yd} fyf_{y} / γms\gamma_{ms}
[Figure 3.9]
 fykf_{yk} / γs\gamma_s
[5.1]
Design strength of reinforcement in compression  fydcf_{ydc} fyf_{y} / γms\gamma_{ms}
[Figure 3.9]
 fykf_{yk} / γs\gamma_s
[5.1]
Maximum linear steel stress  flimf_{lim} fyf_{y} / γms\gamma_{ms}
[Figure 3.9]
 fykf_{yk} / γs\gamma_s
[5.1]
Yield strain in tension ϵplas{\epsilon}_{plas} fyf_{y} /( γms\gamma_{ms}  EsE_s )
[Figure 3.9]
 fykf_{yk} /( γs\gamma_s  EsE_s )
[5.1]
Yield strain in compression ϵplasc{\epsilon}_{plasc} fyf_{y} /( γms\gamma_{ms}  EsE_s )
[Figure 3.9]
 fykf_{yk} /( γs\gamma_s  EsE_s )
[5.1]
Design strain limit ϵsll{\epsilon}_{sll}(10 β\beta -1)×ϵcu\epsilon_{cu}
[6.1.2.4(a) (v)]

Grade 250 0.45

Grade 500B 0.045

Grade 500C 0.0675

[5.1(1) & 5.3(1) CS2:2012 Table 5
UKNA EN1992-1-1]
Maximum concrete strengthfcuf_{cu} \le 100 MPa
[TR 1]
fckf_{ck},cube \le 85 MPa
[5.2.1(2)]
Cmax
Maximum steel strength fyf_{y}  = 500 MPa
[Table 3.1]
 fykf_{yk}  \le 600 MPa
[5.1]
Minimum eccentricitymin{h/20, 20 mm}
[6.2.1.1(d)]
max{h/30, 20 mm}
[5.1]
Minimum area compression reinforcement--
Maximum permitted angle between applied and resulting principal stress φΔ{\varphi}_{\Delta}-

-

Indian Codes

These codes use partial safety factors on materials.

Indian concrete road bridge IRC:112 2011Indian concrete rail bridge IRS 1997Indian building IS456
Concrete strengthfckf_{ck}fckf_{ck}fckf_{ck}
Steel strengthfykf_{yk}fyf_{y}fyf_{y}
Partial safety factor on concrete γC\gamma_{C} = 1.5
[A2.10]
γC\gamma_{C} = 1.5
[15.4.2.1(b)]
γmc\gamma_{mc} = 1.5
[36.4.2.1]
Partial safety factor on steel γS\gamma_{S} = 1.15
[Fig 6.2]
γm\gamma_{m} = 1.15
[15.4.2.1(d)]
γms\gamma_{ms} = 1.15
[36.4.2.1]
Uncracked concrete design strength for rectangular stress block  fcdu{f}_{cdu}fckf_{ck} \le 60 MPa    0.67fckf_{ck}/γC\gamma_{C}

fckf_{ck} > 60 MPa  (1.24-fckf_{ck}/250) ×\times 0.67fckf_{ck}/γC\gamma_{C}

[6.4.2.8 A2.9(2)]
ηfcd{\eta}f_{cd}
0.60fckf_{ck}/γmc\gamma_{mc}
[15.4.2.1(b)]
0.67fckf_{ck}/γmc\gamma_{mc}
[Figure 21]
Cracked concrete design strength (equal to twice the upper limit on shear strength) fcdc{f}_{cdc}fckf_{ck} \le 80 MPa    0.6×\times 0.67fckf_{ck}/γC\gamma_{C}  

80 MPa < fckf_{ck} \le 100 MPa    (0.9-fckf_{ck}/250) ×\times 0.67

fckf_{ck}/γC\gamma_{C}    fckf_{ck} > 100 MPa    0.5 ×\times 0.67fckf_{ck}/ γC\gamma_{C}   

[10.3.3.2]  
ν1fcd{\nu}_1f_{cd}
min {11.875, 1.875 fck\sqrt{f_{ck}} }/  γmc\gamma_{mc} 0.55  
[15.4.3.1]
1.6fck\sqrt{f_{ck}}γmc\gamma_{mc}  0.55  
[Table 20]
Concrete tensile design strength (used only to determine whether section cracked) fcdt{f}_{cdt}fckf_{ck} \le 60 MPa    0.1813fckf_{ck} 2/3/ γC\gamma_{C}  

fckf_{ck} > 60 MPa 1.589 ×\times ln[1.8+ fckf_{ck}/12.5]/γC\gamma_{C}    

[A2.2]  
fcdtf_{cdt}
0.36fck\sqrt{f_{ck}}/ γmc\gamma_{mc}  

[16.4.4.2]
0.5fck\sqrt{f_{ck}}/ γmc\gamma_{mc}  

[From 6.2.2 (70% of  SLS value / γmc\gamma_{mc})]
Compressive plateau concrete strain ϵctrans{\epsilon}_{ctrans}fckf_{ck} \le 60 MPa 0.0018  

fckf_{ck} > 60 MPa 0.00175+ 0.00055 ×\times [(0.8fckf_{ck}-50)/ 40]  

[Table 6.5 & A2.2]  
ϵc3\epsilon_{c3}
0.002  
[assumed]
0.002  
[Figure 21]
Maximum axial compressive concrete strain ϵcax{\epsilon}_{cax}fckf_{ck} \le 60 MPa 0.0018  

fckf_{ck} > 60 MPa 0.00175+ 0.00055 ×\times
[(0.8fckf_{ck}-50)/ 40]   [Table 6.5 & A2.2]  
ϵc3\epsilon_{c3}
0.0035  
[15.4.2.1(b)]
0.002  
[39.1a]
Maximum flexural compressive concrete strain ϵcu{\epsilon}_{cu}fckf_{ck} \le 60 MPa 0.0035  

fckf_{ck} > 60 MPa 0.0026+0.035 ×\times [(90-0.8fckf_{ck})/ 100]4  

[Table 6.5 & A2.2]  
ϵcu3\epsilon_{cu3}
0.0035  
[15.4.2.1(b)]
0.0035  
[38.1b]
Proportion of depth to neutral axis over which constant stress acts β\betafckf_{ck} \le 60 MPa        0.8  

fckf_{ck} > 60 MPa     0.8-(fckf_{ck}-60)/500   [A2.9(2)]  
λ\lambda

[15.4.2.1(b)]
0.84  
[38.1c]
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations  xdmax{\frac{x}{d}}_{max}[upper limit]   1/{1+frac{\epsilon_{s}}{\epsilon_{cu})   <br />where $\epsilon_{s} = 0.002 +fracfyEsγmfrac{f_y}{E_s\gamma_m}  

[15.4.2.1(d)]
fy = 250 0.53  
fy = 415 0.48  
fy = 500 0.46  
[38.1f]  
fracxu,maxd{frac{x_{u,max}}{d}}
Elastic modulus of steel EsE_s200 GPa
[6.2.2]
EsE_s
200 GPa
[Figure 4B]
EsE_s
200 GPa
[Figure 23B]
Design strength of reinforcement in tension  fydf_{yd} fykf_{yk} / γs\gamma_s
[6.2.2]
fydf_{yd}
 fyf_{y} / γm\gamma_{m}
[Figure 4B]
 fyf_{y} / γms\gamma_{ms}
[Figure 23B]
Design strength of reinforcement in compression  fydcf_{ydc} fykf_{yk} / γs\gamma_s
[6.2.2]
fydf_{yd}
( fyf_{y} / γm\gamma_{m} )/[1+ ( fyf_{y} / γm\gamma_{m} )/ 2000]
[15.6.3.3]
fyf_{y} c/ γm\gamma_{m}
 fyf_{y} / γms\gamma_{ms}
[Figure 23B]
Maximum linear steel stress  flimf_{lim} fykf_{yk} / γs\gamma_s
[6.2.2]
0.8 fyf_{y} / γm\gamma_{m}
[Figure 4B]
 fyf_{y} / γms\gamma_{ms}
[Figure 23B]
Yield strain in tension ϵplas{\epsilon}_{plas} fykf_{yk} /( γs\gamma_s  EsE_s )
[6.2.2]
 fyf_{y} /( γm\gamma_{m}  EsE_s ) + 0.002
[Figure 4B]
 fyf_{y} /( γms\gamma_{ms}  EsE_s )
[Figure 23B]
Yield strain in compression ϵplasc{\epsilon}_{plasc} fykf_{yk} /( γs\gamma_s  EsE_s )
[6.2.2]
0.002
[assumed]
 fyf_{y} /( γms\gamma_{ms}  EsE_s )
[Figure 23B]
Design strain limit ϵsll{\epsilon}_{sll}[0.01]
assumed

[0.01]
assumed

[0.01]
assumed

Maximum concrete strengthfckf_{ck} \le 110 MPa
[A2.9(2)]
fckf_{ck} \le 60 MPa
[Table 2]
fckf_{ck} \le 80 MPa
[Table 2]
Maximum steel strength fykf_{yk}  \le 600 MPa
[Table 6.1]
-
 fyf_{y}  \le 500 MPa
[5.6]
Minimum eccentricity0.05 h
[7.6.4.2]
min{0.05 h, 20 mm}
[15.6.3.1]
max{h/30, 20 mm}
[25.4]
Minimum area compression reinforcement---
Maximum permitted angle between applied and resulting principal stress φΔ{\varphi}_{\Delta}-

-

-

Chinese Codes

PR China GB 50010 2002
Characteristic concrete cube strength fcu,kf_{cu,k}  (value after ‘C’ in grade description)
Characteristic steel strength fykf_{yk}  – related to bar type in Table 4.2.2-1
Design concrete strength fcf_{c}   - related to  fcu,kf_{cu,k}  in Table 4.1.4
Uncracked concrete design strength for rectangular stress block
fcduf_{cdu}

 fcu,kf_{cu,k}  \le 50 MPa                 fcf_{c}
fcu,kf_{cu,k}  > 50 MPa                  [1 - 0.002( fcu,kf_{cu,k} -50)]× fcf_{c}
[7.1.3]
α1\alpha_{1} fcf_{c}
Cracked concrete design strength (equal to twice the upper limit on shear strength)
fcdcf_{cdc}

 fcu,kf_{cu,k}  \le 50 MPa           0.4 fcf_{c}
fckf_{ck}  > 50 MPa                0.4×[1 - 0.00667( fcu,kf_{cu,k} -50)]× fcf_{c}
[7.5.1]
0.4 βc\beta_{c}  fcf_{c}
Concrete tensile design strength (used only to determine whether section cracked)
fcdtf_{cdt}
 ftf_{t}   - related to  fcu,kf_{cu,k}  in Table 4.1.4
Compressive plateau concrete strain
ϵctrans\epsilon_{ctrans}

 fcu,kf_{cu,k}  ≤ 50 MPa          0.002
fcu,kf_{cu,k}  > 50 MPa             0.02 + 0.5( fcu,kf_{cu,k} -50)×10-5
[7.1.2]
ϵ0\epsilon_{0}
Maximum axial compressive concrete strain
ϵcax\epsilon_{cax}

 fcu,kf_{cu,k}  ≤ 50 MPa          0.002
fcu,kf_{cu,k}  > 50 MPa             0.02 + 0.5( fcu,kf_{cu,k} -50)×10-5
[7.1.2]
ϵ0\epsilon_{0}
Maximum flexural compressive concrete strain
ϵcu\epsilon_{cu}

 fcu,kf_{cu,k}  ≤ 50 MPa        0.0033
fcu,kf_{cu,k}  > 50 MPa          0.0033 - ( fcu,kf_{cu,k} -50)×10-5
[7.1.2]
ϵcu\epsilon_{cu}
Proportion of depth to neutral axis over which constant stress acts
β\beta
 fcu,kf_{cu,k}  ≤ 50 MPa              0.8
fcu,kf_{cu,k}  > 50 MPa             0.8-0.002( fcu,kf_{cu,k} -50)
β1\beta_{1}
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations
(xd)max{(\frac{x}{d})}_{max}
 β1\beta_{1} /[1+ fyf_{y} /( EsE_{s}  ϵcu\epsilon_{cu} )]
[7.1.4 & 7.2.1]
ξb\xi_{b}
Elastic modulus of steel
EsE_s

 fyf_{y}  < 300 MPa      210 GPa
fyf_{y}  ≥ 300 MPa      200 GPa
[4.2.4]
EsE_{s}
Design strength of reinforcement in tension
fydf_{yd}
 fyf_{y}  – related to  fykf_{yk}  in  Table 4.2.3
Design strength of reinforcement in compression
fydcf_{ydc}
 fy{f'}_{y}  – related to  fykf_{yk}  in Table 4.2.3
Maximum linear steel stress
flimf_{lim}
 fyf_{y}  – related to  fykf_{yk}  in  Table 4.2.3
Yield strain in tension
ϵplas\epsilon_{plas}
 fyf_{y} / EsE_{s}
Yield strain in compression
ϵplasc\epsilon_{plasc}
 fy{f'}_{y} / EsE_{s}
Design strain limit
ϵsu\epsilon_{su}
0.01
[7.1.2(4)]
Maximum concrete strength
 fcu,kf_{cu,k}  \le 80 MPa
[Table 4.1.3]
Maximum steel strength
 fykf_{yk}  \le 400 MPa
[Table  4.2.2-1]
Minimum eccentricity
max{h/30, 20 mm}
[7.3.3]
Minimum area compression reinforcement
0.2% each face
[Table 9.5.1]
Maximum permitted angle between applied and resulting principal stress
φΔ{\varphi}_{\Delta}
-

Canadian Codes

These codes use resistance factors on materials.

CSA A23.3-04CSA A23.3-14CSA S6-14
Compulsory input parameters
Concrete strength fcf_c' fcf_c' fcf_c'
Steel strength fyf_y fyf_y fyf_y
Code parameters that can be overwritten
Resistance factor on concrete
 ϕc\phi_c  = 0.65
[8.4.2]
 ϕc\phi_c  = 0.65
[8.4.2]
 ϕc\phi_c  = 0.75
[8.4.6]
Resistance factor on steel
 ϕs\phi_s  = 0.85
[8.4.3(a)]
 ϕs\phi_s  = 0.85
[8.4.3(a)]
 ϕs\phi_s  = 0.9
[8.4.6]
Derived parameters that can be overwritten
Uncracked concrete design strength for rectangular stress block
fcduf_{cdu}
Max{0.67, 0.85-0.0015 ×\times  fcf_c' } ×\times  ϕc\phi_c  fcf_c'
[10.1.7]
Max{0.67, 0.85-0.0015 ×\times  fcf_c' } ×\times  ϕc\phi_c  fcf_c'
[10.1.7]
Max{0.67, 0.85-0.0015 ×\times  fcf_c' } ×\times  ϕc\phi_c  fcf_c'
[8.8.3(f)]
Cracked concrete design strength (equal to twice the upper limit on shear strength)
fcdcf_{cdc}
0.5 ϕc\phi_c  fcf_c'
[11.3.3]
0.4 ϕc\phi_c  fcf_c'
[21.6.3.5]
0.5 ϕc\phi_c  fcf_c'
[8.9.3.3]
Concrete tensile design strength (used only to determine whether section cracked)
fcdtf_{cdt}
0.37 ϕc\phi_c  \sqrt{ $f_c' }
[22.4.1.2]
0.37 ϕc\phi_c  \sqrt{ $f_c' }
[22.4.1.2]
0.4 ϕc\phi_c  \sqrt{ $f_c' }
[8.4.1.8.1]
Compressive plateau concrete strain
ϵctrans\epsilon_{ctrans}
0.002
[assumed]
0.002
[assumed]
0.002
[assumed]
Maximum axial compressive concrete strain
ϵcax\epsilon_{cax}
0.0035
[10.1.3]
0.0035
[10.1.3]
0.0035
[8.8.3(c)]
Maximum flexural compressive concrete strain
ϵcu\epsilon_{cu}
0.0035
[10.1.3]
0.0035
[10.1.3]
0.0035
  [8.8.3(c)]
Proportion of depth to neutral axis over which constant stress acts
β\beta
Max{0.67, 0.97-0.0025 ×\times  fcf_c' }
[10.1.7(c)]
β1\beta_1
Max{0.67, 0.97-0.0025 ×\times  fcf_c' }
[10.1.7(c)]
β1\beta_1
Max{0.67, 0.97-0.0025 ×\times  fcf_c' }
  [8.8.3(f)]
β1\beta_1
Maximum value of ratio of depth to neutral axis to effective depth in flexural situations
(xd)max{(\frac{x}{d})}_{max}
[upper limit]
(cd)max{(\frac{c}{d})}_{max}
[upper limit]
(cd)max{(\frac{c}{d})}_{max}
[upper limit]
(cd)max{(\frac{c}{d})}_{max}
Elastic modulus of steel
EsE_s
 ϕs\phi_s   ×\times  200 GPa
[8.5.3.2 & 8.5.4.1]
 ϕs\phi_s   ×\times  200 GPa
[8.5.3.2 & 8.5.4.1]
 ϕs\phi_s   ×\times  200 GPa
[8.4.2.1.4 & 8.8.3(d)]
Design strength of reinforcement in tension
fydf_{yd}
 ϕs\phi_s  fyf_y
[8.5.3.2]
 ϕs\phi_s  fyf_y
[8.5.3.2]
 ϕs\phi_s  fyf_y
[8.4.2.1.4 & 8.8.3(d)]
Design strength of reinforcement in compression
fydcf_{ydc}
 ϕs\phi_s  fyf_y
[8.5.3.2]
 ϕs\phi_s  fyf_y
[8.5.3