26.08.2016

Earthquake standard for tower cranes

ISO has published its new standard for tower cranes working in areas at risk of earthquakes, the adoption of which should ensure that a compliant crane will not collapse in the event of an earthquake.

The new ISO 11031 can be used to calculate seismic loads, and sets out design principles for cranes destined to work in seismically active regions and for cranes required to be seismically resistant. The standard was developed at the request of Japan, following the 1995 earthquake in Kobe, emphasized the need for a standard to ensure seismic-resistant cranes. The secretariat of the subcommittee that developed the standard is DIN, the ISO member for Germany.
Please register to see all images

The ISO11031 standard can be purchased online

Klaus Pokorny, Secretary of the ISO subcommittee working on design principles and requirements for cranes, said: “To make sure that cranes are safe, we first need to calculate the seismic loads that show how a crane will respond in moderate to severe earthquakes. Then you can use design limit states provided in two forms: serviceability limit and ultimate limit.”

“The serviceability limit state (SLS) ensures that the crane can withstand the effects of moderate earthquake ground motions throughout its service lifetime and continue to operate as intended. The ultimate limit state (ULS) requires that the crane structure should not collapse during severe earthquake ground motions, and that the suspended load or any other part of the crane should not fall or harm the public, operators and workers”.

“Any evaluation should take into account the regional seismic conditions as well as the ground surface conditions at the crane location. It’s also important to consider how the crane will be used and any risks that could result from seismic damage. Not only will ISO 11031 add a layer of confidence to the industry, it also provides a common technical language so that manufacturers, users and owners understand each other clearly, no matter where they are – a boost for global trade”.

A copy of the standard is available from the ISO online store for 158 Swiss Francs. www.iso.org/iso/catalogue_detail?csnumber=46588