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55 Fire developed at a partially complete 14 level multistory building at. A fire grew with temperatures estimated at around 1000°C and although structural steel is estimated to become elastic at around 600°C however, some structural beams were deformed but no structural failure occurred and the integrity of the floor slabs were maintained (constructed using longspan lattice trusses and beams supporting concrete slabs) throughout the fire. The building construction was not completed therefore contained no passive fireprotection on the steelwork. The sprinkler systems & other active measures were not yet commissioned and not in operation. Following the fire, it was observed that no connections had failed. However, there were deformations of bolt holes, broken bolt heads, and some of the connection plates had fractured along the length of their beams but had still managed to transfer shear appropriately, various levels of deformation observed in support structures, those deformations were due to tensile forces induced during cooling. The estimated cost of damage was around £25m Structural analysis following the fire proved that fire protection for structural elements are over specified and are not required as much as once thought, fireengineering principles can be applied to reduce the cost of fire protection and therefore cost of construction. This became a catalyst for steel companies to carry out research in order to gain an economical benefit which has shown that the inherent fire resistance of this common structural framing system is far greater than is demonstrated using standard fire tests. In the Cardington large scale fire tests it was shown that unprotected beams which would fail within 20 minutes for a simply supported structure using a standard fire test could in fact survive offering over one hour fire resistance. This finding now underpins much of modern structural fire engineering Broadgate, London 1990 Event Statistics Unknown Lessons Learned Duration of fire Number of casualties Cost to industry References None £25 million Broadgate Investigation. 1990.[Online]. [Accessed 31 October 2014]. http://www.mace.manchester.ac.uk Prof.Andwers. Broadgate incident. Fire Explosion Prediction & Investigation, October, 2014, Weetwood Hall Leeds. Type of fire Construction Fire Unknown Ignition Source

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Page 1: Broadgate,*London* - Fire

55

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Fire  developed  at  a  partially  complete  14  level  multistory  building  at.  A  fire  grew  with  temperatures  estimated  at  around  1000°C  and  although  structural  steel  is  estimated  to  become  elastic  at  around  600°C  however,  some  structural  beams  were  deformed  but  no  structural  failure  occurred  and  the  integrity  of  the  floor  slabs  were  maintained  (constructed  using  longspan  lattice  trusses  and  beams  supporting  concrete  slabs)  throughout  the  fire.  The  building  construction  was  not  completed  therefore  contained  no  passive  fire-­‐protection  on  the  steelwork.  The  sprinkler  systems  &  other  active  measures  were  not  yet  commissioned  and  not  in  operation.  Following  the  fire,  it  was  observed  that  no  connections  had  failed.  However,  there  were  deformations  of  bolt  holes,  broken  bolt  heads,  and  some  of  the  connection  plates  had  fractured  along  the  length  of  their  beams  but  had  still  managed  to  transfer  shear  appropriately,  various  levels  of  deformation  observed  in  support  structures,  those  deformations were  due  to  tensile  forces  induced  during  cooling.  The  estimated  cost  of  damage  was  around  £25m    

2

Structural  analysis  following  the  fire  proved  that  fire  protection  for  structural  elements  are  over  specified  and  are  not  required  as  much  as  once  thought,  fire-­‐engineering  principles  can  be  applied  to  reduce  the  cost  of  fire  protection  and  therefore  cost  of  construction.    

This  became  a  catalyst  for  steel  companies  to  carry  out  research  in  order  to  gain  an  economical  benefit  which  has  shown  that  the  inherent  fire  resistance  of  this  common  structural  framing  system  is  far  greater  than  is  demonstrated  using  standard  fire  tests.    

In  the  Cardington  large  scale  fire  tests  it  was  shown  that  unprotected  beams  which  would  fail  within  20  minutes  for  a  simply  supported  structure  using  a  standard  fire  test  could  in  fact  survive  offering  over  one  hour  fire  resistance.  This  finding  now  underpins  much  of  modern  structural  fire  engineering  

 

Broadgate,  London  1990  

Event    Statistics  

Unknown  

Lessons  Learned  

Duration  of  fire  

Number  of  casualties  

Cost  to  industry  

References    

None  

£25  million  

Broadgate  Investigation.  1990.[Online].  [Accessed  31  October  2014].  http://www.mace.manchester.ac.uk  Prof.Andwers.  Broadgate  incident.  Fire  Explosion  Prediction  &  Investigation,  October,  2014,  Weetwood  Hall  Leeds.  

Type  of  fire  Construction  Fire    

Unknown  Ignition  Source  

Page 2: Broadgate,*London* - Fire

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Fire  at  Hays  business  located  at  Gillender  st,  London  had  a  number  of  events  that  hampered  the  efforts  of  the  fire  fighting  crews.    Firstly  employees  delayed  for  seven  minutes  after  the  fire  alarm  went  off  before  calling  the  brigade.    Fire  crews  located  the  fire  early  in  the  incident  and  laid  a  hose.  However,  it  was  never  used,  despite  the  manual  of  firemanship  stating  that  water  should  be  applied  to  a  fire  as  soon  as  possible.      There  were  major  failings  in    

o Command  and  control,    o Failure  to  debrief  crews,    o Failure  to  protect  members  against  

heat  stress,    o Failure  to  organise  reliefs,    o Failure  to  organise  ventilation    o Failure  to  organise  firefighting  in  

general  

This  unfortunately  these  inefficiencies  led  to  the  deaths  of  two  firefighters  namely  Stokes  and  Hunt.      

2

Mr  Hunt,  33,  from  Chadwell  Heath,  Essex,  and  Mr  Stokoe,  25,  from  Hornchurch,  Essex,  died  after  running  out  of  breathing  apparatus  oxygen    Following  an  investigation  The  HSE  served  two  improvement  notices  taking  action  against  the  fire  brigade    The  serving  of  the  notices  is  revealed  in  a  report  sent  to  all  114  fire  stations  by  Brian  Robinson,  Chief  Fire  Officer  and  director  of  operations  for  London.    The  key  outcome  form  the  enquiry  has  prompted  better  training  for  the  Fire  Brigade  to  avoid  such  failures  in  the  future.          

Gillender  St,  London    July  10,  1991  

Event    Statistics  

 Several  hours    

Lessons  Learned  

Duration  of  fire  

Number  of  casualties  

Cost  to  industry  

References    

2  Fire  Fighter  Casualties  

2  lives  of  fire  service  personnel,  the  rebuild  of  the  building    

Heys  Business,  Gillender  St  London.  1991.[Online].  [Accessed  8  November  2014].  http://www.independent.co.uk/news/uk/fire-­‐brigade-­‐told-­‐to-­‐reform-­‐training-­‐after-­‐blaze-­‐deaths-­‐1555689.html    

Type  of  fire  Hydrocarbon    

Arson  /  Deliberate    Ignition  Source