How is bridge demolition done?

[longhorn]

https://twitter.com/i/status/1382792924312739843

Curious how did they get deck to pancake like that? Minor explosives on the supports? Yet traffic is flowing on the other side.

[bwana39]

My guess is the jackhammer on the boom of the excavator finally made the final cut to release the tension. 

[The Ghostbuster]

I suppose using dynamite would be too dangerous and too messy.

[abqtraveler]

My guess is the jackhammer on the boom of the excavator finally made the final cut to release the tension.

Just weaken the support columns enough and the bridge will collapse under its own weight.