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Tawfik | Expert Forensic & Materials Engineers
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FORENSIC INVESTIGATION TO DETERMINE IF METAL FATIGUE WAS LINKED TO RECENT FATAL AMUSEMENT RIDE ACCIDENT

An engineering failure investigation is underway to determine the cause(s) of the sudden structural failure and catastrophic detachment of a steel spoke section from a spinning thrill ride during mid-flight while carrying multiple riders resulting in one fatality and multiple casualties on July 27, 2017 at Ohio. The investigation findings into the 19 year old ride should ascertain the failure mechanism(s) and determine whether it was inappropriately operated, poorly designed, poorly fabricated, operated beyond its usable design life, poorly maintained and/or routinely inspected.

Examination of the fractured section(s) including metallurgical/mechanical testing of the steel spoke section associated with the failed section will ascertain the failure mechanism(s) and identify any associated defects. The type, extent and location of the routine inspections/maintenance and non-destructive examination records should reveal whether incipient damage, and/or progressive deterioration were known particularly in the location associated with this tragic accident. Similar rides in service may need to cease operation to assess the risk of a similar failure mode.
http://www.wkyc.com/news/local/ohio/was-something-missed-during-inspections-at-the-ohio-state-fair/460059121
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ENGINEERING MODELLING CAN NOW SIMULATE THE DETAILED COLLAPSE SEQUENCE OF COMPLEX STRUCTURES IN EARTHQUAKE PRONE LOCATIONS INCLUDING THE EFFECTS ON SEARCH AND RESCUE ACCESSIBILITY.

CASE STUDY: Burnside Bridge, Portland, Oregon USA
( CLICK ON THE LINK https://lnkd.in/gKxUk77)

BRIDGE TYPE: Bascule span, truss (deck: concrete, truss: wrought iron/steel)

AGE OF THE STRUCTURE: 91 years

EARTHQUAKE MAGNITUDE THRESHOLD: 8.0

LIKELIHOOD OF EARTHQUAKE MAGNITUDE: HIGH

DEVASTATION: Catastrophic, destroyed (layman: finito)

Click on the link below to watch the simulation of the burnside bridge collapsing under an 8.0 magnitude earthquake.

https://lnkd.in/gKxUk77
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Role and ethics of a forensic engineer while undertaking an investigation. Contrary to popular social belief, its isn't akin to the CSI tv drama...unless you read their complicated report findings http://thevarsity.ca/2017/01/08/forensic-engineering-isnt-all-csi/
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"FAILURE RISK OF AGED AWNINGS IN PUBLIC PRECINCTS" https://www.linkedin.com/pulse/failure-risk-aged-awnings-public-precincts-dr-david-tawfik by @Tawfikgroup on @LinkedIn
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Accelerated wheel wear paralyses Victorian regional train network
The rapid wheel wear detected on a fleet of regional passenger rail cars has reportedly been implicated with the suspension of approximately 80% of Victorian train services across the regional network since January 2016.

The immediate suspension of the affected Vlocity DMU (Diesel Multiple Units) train sets from service was implemented by the operator, V/line for safety precautions to avoid the elevated risk of any derailment incidents.

The consequence of this incident has caused extensive transportation delays to regional train passengers, and activated an impromptu maintenance/replacement regimes for the track infrastructure and train wheel sets for several months.


http://www.linkedin.com/pulse/accelerated-wheel-wear-paralyses-victorian-regional-train-tawfik?trk=pulse_spock-articles
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Growing fire risk in residential towers amid poor quality aluminium facades infiltrating construction

An investigation in to November 2014 fire incident at the Lacrosse high rise apartments by the Melbourne Fire Brigade (MFB) revealed that the external walls were constructed from combustible materials and hence, contravened the Building Code of Australia. 
The external walls of the Lacrosse high rise which consisted of aluminium composite panels had contributed to the vertical propagation of the flames, leading to an uncontained fire over numerous floors in a matter of minutes.
Further investigation suggest the aluminium composite panels comprised of a polyethylene core. Polyethylene is consistent with a common type of plastic/polymer type material.  Independent tests were undertaken in accordance with Australian Standards 1530.1 Combustibility Test for Materials to interrogate the combustion and flame propagation characteristics of the aluminium composite panels used in the Lacrosse high rise. The test findings confirmed that the aluminium composite panels did not comply with AS 1530.1-1994 which condemns it as a prohibited combustible material for use in this type of building structure.
Aluminium composite panels implicated with spreading of vertical fires in high rises has been widely reported in literature for over eight years particularly in the United Arab Emirates;  See table below & images below. Approximately 70% of high rise tower constructed in the United Arab Emirates comprise of aluminium composite panel with a combustible thermo-plastic type cores similar to that used in the Lacrosse residential tower in Melbourne.
 It is not uncommon for foreign cladding suppliers to endorse a fire resistance grade to their construction products in accordance with international standards or designation without proper testing or independent certification. This can lead to false interpretations about their actual combustibility characteristics in accordance with Australian Standards unless carefully review by an appropriately qualified expert.

The use of aluminium cladding in high rise construction have reportedly been used for decades in Australia. It is unclear as to how many high rise developments in Australia have utilised non-compliant aluminium cladding unless a comprehensive audit is undertaken.

A senate inquiry in to the safety and compliance of imported construction materials in Australia has been established amid growing trends in use of non-compliant structural steel, fasteners, glass panels, electrical cabling  and aluminium cladding.



References:
http://www.thenational.ae/business/property/the-torch-blaze-reignites-concerns-over-cladding-used-for-dubai-towers
http://www.telegraph.co.uk/news/worldnews/middleeast/dubai/11427715/Dubai-Marina-Torch-Tower-fire-Londoner-tells-of-how-he-slept-through-a-towering-inferno.html
http://www.constructionweekonline.com/article-19692-fire-and-safety-code-amended-on-exterior-cladding/
http://www.abc.net.au/news/2015-05-27/cheap-cladding-turns-apartments-into-time-bombs/6501716
http://www.thenational.ae/news/uae-news/sharjah-families-back-in-al-tayer-fire-tower
http://www.constructionweekonline.com/article-16634-sharjah-al-baker-tower-fire-caused-by-cigarette/
MFB Post Incident Analysis Report, Lacrosse Docklands 673-675a La Trobe Street Docklands
http://www.fireengineering.com/articles/2010/05/modern-building-materials-are-factors-in-atlantic-city-fires.html
http://www.nickxenophon.com.au/media/releases/show/safety-check/
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Significant deterioration plaguing numerous residential towers on Gold Coast

Dozens of steel reinforced concrete residential towers on the Gold Coast which are nearing the end of their design life (40-50 years) are reported to exhibit significant concrete deterioration in the form of concrete cancer.

Concrete cancer is a natural yet major degradation process in reinforced concrete structures caused by the expansion of the embedded steel reinforcement due to steel rusting.

Rusting of embedded steel reinforcement can be caused by the gradual loss of the concrete’s passive protection to the steel through carbonation and/or exposure of steel reinforcement through Chloride ion (i.e. Salts) penetration.

Concrete cancer is more prevalent in reinforced concrete structures exposed in harsh marine environments (i.e. beach side) where the atmosphere contains high levels of airborne salts from the sea and exhibits higher humidity.

Rusting of the embedded steel reinforcement causes it to expand in volume thus creating tensile stresses in the concrete which leads to cracking, delamination and spalling of concrete segments. This exposes adjacent sections of embedded steel reinforcement to the environment which undergo rusting thus perpetuating and propagating the degradation process of concrete which eventually comprises the structural integrity of the structure if unattended.

The falling of spalled concrete segments from the Gold Coast high rises may also create a serious hazard to human life or property if the issue is left unattended.

The legislation of Queensland’s Body Corporate Community Act is reportedly under review to ensure steel reinforced building structures in the Gold Coast are appropriately inspected, maintained and adequately repaired.

However the repair cost of concrete cancer in some residential towers can be exorbitant to reinstate it to the minimum structural standard requirements. Such a scenario, may result the tower to be condemned and eventually demolished.

http://www.brisbanetimes.com.au/queensland/time-up-for-gold-coast-high-rise-as-concrete-cancer-warnings-loom-20150616-ghop5g.html


Reference:
Time up for Gold Coast high rise as concrete cancer warnings loom, June 16, 2015, Brisbane Times
Warning to check for 'concrete cancer' in older unit high rise complexes, Cairns Post, Nick Dalton, January 15, 2014
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Fatalities and multiple injuries in the Gulf of Mexico accident caused by a collapsed oil platform
 
An incident occurred on Tuesday 5 May 2015, where a Petroleos Mexicanos owned oil platform in the Gulf of Mexico experienced a partial collapse to one its legs during a manoeuvre to undertake offshore maintenance resulting in 2 fatalities, 10 injuries and evacuation of over 100 personnel.
 
The collapse of a platform leg is reportedly implicated with structural failure which ultimately caused the tilting and partial sinking of the entire jack-up type platform.  An oil slick was reportedly detected in the area although the extent of oil leak is unconfirmed.
An investigation to the cause of the accident and structural failure has been announced by federal prosecutors.
 
Reference: Johnson T. 2 dead as Mexican odfshore oil rig collapses in Gulf,  Sunherald, May 5, 2015
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