BSMI revises high strength steel standard to enhance anti-seismic property in buildings BSMI, MOEA August 13, 2018


To reduce the damage of buildings and injury in the event of an earthquake, the Bureau of Standards, Metrology & Inspection (BSMI) has revised the CNS 560 “Steel bars for concrete reinforcement” based on the ASTM International standard. The decision was made after referencing standards from several advanced countries.

High strength steel SD 550 W (W means that the steel can be used for wielding and as anti-seismic construction material) and SD 690 are now under the scope of the revised CNS 560 because they can sustain the stress of 550 MPa and 690 MPa, relatively. The BSMI said that the steels can enhance a building’s anti-seismic property significantly and are expected to be widely applied to the construction of high-rise buildings, adding that they can reduce the cross section area of the construction part and better support buildings during earthquakes.

The key points of the revision are as follows:
1) Addition of high strength steel: In the past, reinforced concrete(RC) was mainly used on buildings less than 20 floors tall because of steel strength limits. With the improvement of manufacturing technology, reinforced concrete can also be used to build skyscrapers. As an example, a 59 floor high RC building has been successfully built abroad.
2) Increase of elongation: Giving the steel more tenacity to absorb energy released from an earthquake.
3) Increase of welding property: Preventing steel fragility caused by cooling after heating during the welding process. Weldable steel is mainly used in the welding of steel and structure in steel reinforced concrete(SRC) structures.
4) Identification of heat tempered steel(also called as controlled-rolling manufactured steel): Heat tempered steel has uneven quality and cannot guarantee anti-seismic property. Although heat tempered steel has been eliminated from the scope of the CNS 560 since 2014, heat tempering identifying method is added to prevent poor quality steel from being marketed.

Taiwan is located on a seismically active region and hundreds of sensible earthquakes take place every year. As 90 percent of the buildings in Taiwan are made out of reinforced concrete, the quality of steel is an important indicator of good anti-seismic property. The revised CNS 560 serves as a guideline for all to follow.

For more information about CNS 560, please visit the CNS Online Service at

Agency in charge: Department of Standards (First Division) Contact person: Ms. Shiu-Nu Chen
Telephone: (02)3343-5110

  • 編修日期:2018/10/02
  • 上稿單位:第一組第一科
Latest Update: 2020年7月3日