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Chemical anchors - do they have a fire rating? and how much of its tensile and shear capacity reduces due to fire?

Posted by Kirpalalmost 4 years ago
Chemical anchors - do they have a fire rating? and how much of its tensile and shear capacity reduces due to fire?

Chemical anchors - do they have a fire rating? and how much of its tensile and shear capacity reduces due to fire?

Anchor,Fire,Masonry
2 Replies
Posted by Team Ask Hiltialmost 4 years ago
Hilti Verified

7 Days ago

Thank you for your question.  There is published data available for the performance of chemical anchors within Fire Conditions with the load values based upon 30 minute intervals typically up to 2 hours for anchor connections. 

Fire
1 comment on this reply
Posted by Jagodaalmost 2 years ago
Good afternoon, could you please advise where this data can be found? In Hilti technical library I have only found the guidance with the reduced tensile capacity and I would be interested in learning about reduced shear capacity as well. Thank you.
Posted by Team Ask Hiltialmost 2 years ago

Thank you for the question the tensile load is actually the more onerous case. A shear load would be considered as having the same fire resistance value.

4 comments on this reply
Posted by Jagodaalmost 2 years ago
Thank you, could you please confirm if I understand this correctly - the loads in the fire condition will be smaller than in the non-fire case, so checking the non-fire case with full loading should be sufficient for fixings that transfer only shear? Also, could this way of checking shear connections in fire condition be used in the case where there are more than 4 bolts in the connection and hilti filling set needs to be used to ensure the shear force is equally transferred to all anchors?
Posted by Team Ask Hiltialmost 2 years ago
Hello, typically in a fire condition I would expect the load being applied to the anchor to be reduced so by checking if the non fire load condition meets the criteria at the 30 , 60 minutes etc is a conservative approach.
Posted by Jagodaalmost 2 years ago
Hello, one more question from me - so actually, in the case where we only have the shear forces, would you assume it is enough to check the connection in the normal load case? As the Profis Engineering software does not perform fire checks for resin anchors.
Posted by Jagodaalmost 2 years ago
That's good news, thank you for the prompt response!