Editing Cascading failure (section)

== Cascading structural failure ==
Certain load-bearing structures with discrete structural components can be subject to the "zipper effect", where the failure of a single structural member increases the load on adjacent members.  In the case of the [[Hyatt Regency walkway collapse]], a suspended walkway (which was already overstressed due to an error in construction) failed when a single vertical suspension rod failed, overloading the neighboring rods which failed sequentially (i.e. like a [[zipper]]). A bridge that can have such a failure is called fracture critical, and numerous bridge collapses have been caused by the failure of a single part. Properly designed structures use an adequate [[factor of safety]] and/or alternate load paths to prevent this type of mechanical cascade failure.<ref name="petroski">{{cite book| title=To Engineer Is Human: The Role of Failure in Structural Design| first=Henry| last=Petroski| year=1992| isbn=978-0-679-73416-1| publisher=Vintage| url-access=registration| url=https://archive.org/details/toengineerishuma00petr}}{{pn|date=March 2025}}</ref>

===Fracture cascade===
[[File:Sequential fractures - Fracture cascade -- Smart-Servier.jpg|thumb|Chain reaction of osteoporotic fractures]]
Fracture cascade is a phenomenon in the context of geology and describes triggering a chain reaction of subsequent fractures by a single fracture.<ref>{{cite book |doi=10.1201/9781315151052 |title=Fractals in Soil Science |date=2017 |isbn=978-1-315-15105-2 |editor1-first=Philippe |editor1-last=Baveye |editor2-first=Jean-Yves |editor2-last=Parlange |editor3-first=Bobby A |editor3-last=Stewart |chapter=Fractal Geometry, Fragmentation Processes and the Physics of Scale-Invariance: An Introduction |first1=P |last1=Baveye |first2=C W |last2=Boast }}</ref> The initial fracture leads to the propagation of additional fractures, causing a cascading effect throughout the material.

Fracture cascades can occur in various materials, including rocks, ice, metals, and ceramics.<ref name=spaghetti>{{cite journal |last1=Heisser |first1=Ronald H. |last2=Patil |first2=Vishal P. |last3=Stoop |first3=Norbert |last4=Villermaux |first4=Emmanuel |last5=Dunkel |first5=Jörn |title=Controlling fracture cascades through twisting and quenching |journal=Proceedings of the National Academy of Sciences |date=28 August 2018 |volume=115 |issue=35 |pages=8665–8670 |doi=10.1073/pnas.1802831115 |pmid=30104353 |pmc=6126751 |arxiv=1802.05402 |bibcode=2018PNAS..115.8665H |doi-access=free }}</ref> A common example is the bending of dry [[spaghetti]], which in most cases breaks into more than 2 pieces, as first observed by [[Richard Feynman]].<ref name=spaghetti/>

In the context of [[osteoporosis]], a fracture cascade is the increased risk of subsequent bone fractures after an initial one.<ref>{{cite journal |last1=Melton |first1=L Joseph |last2=Amin |first2=Shreyasee |title=Is there a specific fracture 'cascade'? |journal=BoneKEy Reports |date=26 June 2013 |volume=2 |page=367 |doi=10.1038/bonekey.2013.101|pmid=24575296 |pmc=3935254 }}</ref>