Earthquake-resistant construction17. November 2020
Earthquakes can have disastrous effects on natural and built surroundings, which is why buildings must be made earthquake resistant. The formation and design of fastenings under seismic load is regulated by EN 1992-4, among others. Prof. Dr. Eng. Jan Hofmann talks about earthquake-resistant construction and outlines the effects on fastenings in our OnlineSeminar. Here we provide the answers to participant questions.
How do I approach anchor designs with seismic requirements and stand-off installation?
In this case please note that stand-off installation for designs under seismic load are not permissible.
Participant question: When are EN 1998-1/NA draft:2020-05 and EN 1998-1/NA-draft:2020-05 expected to be introduced via building laws?
Unfortunately there is no information available about this.
Earthquake-resistant construction: Planning assistance with the Eurocode 8 standards
Participant question: Technical Reports (TR) are available for design purposes in connection with other construction products with an ETA. Is this still required in this case due to the existing 1992-4 standard?
TR 45 was used for design purposes up until recently. Published in early 2019, the EN 1992-4 standard comprehensively regulates the design of fastenings in concrete as Part 4 of Eurocode 2, replacing a multitude of old guidelines and technical reports. EN 1992-4 represents the latest standards in technology and increases the level of safety for the user in addition to the transparency of anchor design. fischer’s white paper provides an overview of everything you need to know about this.
Participant question: Do fastenings with dynamic approval need to be used?
No, anchors with dynamic approval are tested in relation to fatigue. Seismic load anchors meanwhile are tested in relation to larger widths. These are two different approaches.
Solutions for fastening designs
Participant question: What needs to be taken into account when working with masonry?
There are currently no further details on fastenings in masonry. We would generally recommend a fastening that is as redundant as possible and selecting the largest possible anchoring depths and diameters. Prof. Hofmann furthermore recommends oversizing the anchor and using components that permit major deformation and ductility.
Participant question: Which earthquake zones correspond to performance categories C1 and C2?
These performance categories are irrelevant in Germany, where the building’s structural design is decisive, meaning the expected crack width. There are no requirements up to 0.3 mm. C1 is up to 0.5mm and C2 is above that and up to 0.8 mm.
Participant question: Which type of load should anchors with approval in cracked concrete currently be designed for: for static/quasi-static loads or seismic loads?
Both if the design is required for earthquakes, otherwise either just static or quasi-static.
It is difficult to anticipate when and where a strong earthquake will occur, which is why it is better to take precautions in order to protect yourself. Collapsing houses and structures present the greatest dangers during an earthquake. In addition to various methods, anchors can help buildings withstand the tremors. We spoke to fischer Application Engineer Oliver Ernst about earthquake-resistant construction.