Investigation of Grade 500E

An investigation into the concerns about Grade 500E was launched in August 2003.

Our investigations included:

  • asking ACENZ members to report any problems with Grade 500E steel (ACENZ members are consulting professionals in the built and natural environment)
  • reviewing available data on specimens that had been referred to the manufacturer Pacific Steel
  • commissioning a report from Beca Consultants on the adequacy and compatibility of the various Standards covering the manufacture, design, welding and handling of Grade 500E reinforcing steel
  • commissioning a series of tests by Auckland testing laboratory, SGS, on bars nominally sold as Grade 500E, both locally manufactured and selected imported products, to determine their physical properties
  • investigating the parameters that govern allowable bend diameters.

Results of the investigation into these issues in general terms were as follows.

  • very few problems were reported by ACENZ members
  • most site problems referred to Pacific Steel, or separately reported to the us, were the result of mishandling the bars and not following the relevant Standards
  • Beca Consultants reported no serious incompatibilities or inadequacies of the various reinforcing Standards. This report did, however, highlight the need for research into safe bend diameters for Grade 500E, as referred to below
  • results of the SGS testing were generally satisfactory, but there were a small number of individual tests that did not reach specified Standards. These anomalies were referred to the specific suppliers.

This information is published by the Ministry of Business, Innovation and Employment’s Chief Executive. It is a general guide only and, if used, does not relieve any person of the obligation to consider any matter to which the information relates according to the circumstances of the particular case. Expert advice may be required in specific circumstances. Where this information relates to assisting people: