With standards often being changed, revised, and having additions made, a history of what standards may have been applicable at the time of build is a resource well worth having.  Below is a summary of some of the previous reinforcing steel Standards in New Zealand.  All current Standards are available for purchase from the Standards NZ website www.standards.co.nz

Please note this table is a summary for reference only and should not be deemed as a true and correct record.

 

 

 

 

 

 

 

 

Standard number

Year Issued

Title  (Details)

Yield Strength

Tensile Strength

Elongation

C

%w/w

P  

%w/w

S  

%w/w

CE  

%w/w

NZSS 197

(BS 785:1938)

1949

Rolled Steel Bars and Hard Drawn Steel Wire for Concrete Reinforcement

(Adoption of BS 785.  Most properties varied with diameter)

Not stated

62,720 – 73,920psi

min. 16/20/24% on 5x diam’

---

0.060

0.060

---

39200/ 41440/ 43680

73,920 – 85,120psi

min. 14/18/22% on 5x diam’

---

0.060

0.060

---

NZSS 1693

1962

Deformed Steel Bars of Structural Grade for Reinforced Concrete  (Deformed hot-rolled bars)

min. 33,000 psi

55,000 – 75,000 psi

min. 20% on 5x diam’

---

0.060

0.060

---

NZSS 1879

1964

Hot Rolled Deformed Steel Bars of HY 60 Grade

(High Yield 60 000 psi) for Reinforced Concrete.

(Not normally weldable.  Deformation factor of 0.925 meant the bars really only needed to be 55,500 psi)

min. 60,000 psi

1.2 x YS, but min. 90,000 psi

min. 12% on 5x diam’

0.40

0.050

0.050

---

NZSS 1693

Amendment 1

1968

 

min. 40,000 psi

55,000 – 75,000 psi

min. 20% on 5x diam’

---

0.060

0.060

---

NZSS 1879

Amendment 1

1970

(added 1.5 inch bar)

min. 60,000 psi

1.2 x YS, but min. 90,000 psi

min. 12% on 5x diam’

0.40

0.050

0.050

---

NZSS 1879

Amendment 2

1972

(reduces testing frequency from once in every 10 tons to once in every 25 tons)

min. 60,000 psi

1.2 x YS, but min. 90,000 psi

min. 12% on 5x diam’

0.40

0.050

0.050

---

NZS 3423P

1972

Hot Rolled Plain Round Steel Bars of Structural Grade for Reinforced Concrete  (Metric & imperial units)

min. 40,000 psi

55,000 – 75,000 psi

min. 20% on 5x diam’

0.25

0.060

0.060

---

NZS 3402P

1973

Hot Rolled Steel Bars for the Reinforcement of Concrete

(Metric units, superseded 1693, 1879 & 3423P.  Non specific bar mark introduced for 380 grade )

min. 275MPa

380 – 520MPa

min. 20% on 5x diam’

0.25

0.060

0.060

---

min. 380MPa

min. 570MPa (min. 1.2 ratio)

min. 12% on 5x diam’

0.40

0.050

0.050

---

NZS 3402

1989

Steel Bars for the Reinforcement of Concrete

(Use of characteristic ranges for yield and tensile ratio. Both grades are readily weldable.  Bar marking of all deformed bar and plain 430 grade for grade and manufacturer )

300 - 355MPa

1.15 – 1.50 ratio

min. 20% on 5x diam’

0.22

0.050

0.050

0.45

430 - 500MPa

1.15 – 1.40 ratio

min. 15% on 5x diam’

0.22

0.050

0.050

0.51

AS/NZS 4671

2001

Steel Reinforcing Materials

(Joint materials Standard.  Change to grade 500E for NZ, further development of the characteristic values to include uniform elongation)

300 - 380MPa

1.15 – 1.50 ratio

min. 15.0% uniform

0.22

0.050

0.050

0.43

500 - 600MPa

1.15 – 1.40 ratio

min. 10.0% uniform

0.22

0.050

0.050

0.49

AS/NZS 4671

Amendment 1

2003

(Amends reference to external documents, changes some testing frequencies and the application of statistical analyses)

300 - 380MPa

1.15 – 1.50 ratio

min. 15.0% uniform

0.22

0.050

0.050

0.43

500 - 600MPa

1.15 – 1.40 ratio

min. 10.0% uniform

0.22

0.050

0.050

0.49

 

NB: Italicized underlined figures are characteristic limits