Term
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Definition
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Overload
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To load something to excess
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Redundancy
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The inclusion of extra components which are not strictly necessary to functioning, in case of failure of other components.
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Introduction
Earlier in the year, I read an article on the many different types of failures encountered during the building of the Humber Bridge in the UK. This article put me in search of other bridge-related failures but this time I looked for examples where overload was a contributing factor in the collapse of the bridge itself. Some examples go to great depths detailing how particular bridges were sized, the materials systems and processes used to build them, what caused them to fail, and the various governmental and engineering innovations that followed failure events to mitigate future risk. There is one bridge failure that I explored over a number of books and various online materials as this event was to prove pivotal in the way that it acted as a catalyst for governments and engineers to come up with new approaches for the design, regulation and lifecycle management of bridges in the United States.
The Silver Bridge Collapse
At approximately 5pm on Friday, December 15th 1967 the Silver Bridge collapsed into the Ohio River – tragically killing forty-six people.
At the time the bridge was built in 1928 the typical car was a Ford Model-T that weighed around 1,600 lbs and local law prohibited any truck that was more than 20,000 lbs. The bridge was designed with a safety factor of 1.5 so was capable of supporting cars up to 2,400 lbs and trucks up to 30,000 lbs.
As the years passed, vehicles got heavier, and by the sixties, a typical car now weighed 4,000 lbs, with trucks weighing up to 60,000 to 70,000 lbs. The loads had almost tripled.
In the years before its collapse back to back traffic was typical and the tools and processes at the time used for bridge inspection were not capable of identifying a fracture that appeared in one of the eye-bars. Stress corrosion and corrosion fatigue where listed as the probable cause with loading being a major factor that helped collapse the bridge. The following year, then President Lyndon Johnson and Congress brought into law the National Bridge Inspection Standards, and the United States Department of Transport enforced tighter regulations around weight limits. The regulations also enforced regular inspection and brought with it the start of a national database holding construction and inspection information of all federal bridges.
Inspection, loading and redundancy are key elements associated with bridge engineering, and indeed they are also crucial elements of modern information technology infrastructure systems.
Taking DellEMCs VMAX & PowerMax product range as an example (the other products have similar), some great tools enable the presales sizing function and post-sale performance management.
- Sizing: VMAX Sizer Gives subject matter experts from Dell EMC and selected partners the ability to size a solution based on your business objectives, capacity and workload requirements.
- Performance Management: Unisphere offers real-time component health, response time alerting, component performance utilization, capacity utilization and enables pro-active decision making so you can make informed decisions about when its time to scale-up or scale-out.
- Maintenance: Secure Remote Services (formerly ESRS) gives subject matter experts from Dell EMC secure access to systems during support activities and regular maintenance.
Talk to your local sales team!
Thanks for reading and please feel free to leave comments or feedback.
