Braxton Kyle Bensel
G#: 801101065
Click this, this is cool!Return to my home page.
Return to my 2156 Portfolio.
Learn more about me!
Assignment 3A: Engineering Disaster Analysis
The HMS Titanic
The HMS Titanic was a British passenger liner that is infamous for its wreck that resulted in hundreds of lost lives. The Titanic was owned by the British shipping company the White Star Line. On April 15th, 1912, it sunk while on its maiden voyage to the United States. There were around 2,500 souls aboard, of which 700 survived. The disaster had a plethora of reasons, ranging from poor rivets to poor steel to a failure to notice the iceberg to a failure of another boat to provide assistance. We'll be taking a closer look at the mechanical failures (and successes) of the RMS Titanic.
The Initial Impact and Effects
The initial impact of the iceberg resulted in the rupturing of five of the sixteen compartments on the ship. Ships are designed with the hull being split into a number of compartments that can be sealed off in the event of a rupture. This means that the boat limits the amount of water that can enter the ship. With five of the fifteen compartments filling with water, the Titanic began to quickly gain mass on it's front side and tip towards the front greatly. This then pulled the ship out of the water, giving it the iconic forward tip. The split of the boat was a simple result of the forces of the boat exceeding that of the Shear Force of Steel (80 GPa).
As is visible by the image, as more and more water filled the ship, the bouyant force was reduced and the forces due to gravity were increased. This, combined with the fact that the opposite end was not being filled with water created uneven loading that caused the steel in the center of the boat to shear and the boat split in half. The forces of the boat were simply too much for the steel to handle.
The Rivets
Another key element that historians believe resulted in the failure of the ship was the quality of the metal used in the rivets. Wrought Iron, as mentioned in MEGR 2180: Manufacturing Systems, typically has a slag content of around 2-3%. The slag is a byproduct of iron production, and is typically removed through refinement. The slag content of some of the analyzed rivets had slag levels of nearly 9%, which could have been a contributing factor to the failure of the ship. If the actual maximum bearing stress of the pins was less than what was believed, then the bearings could have failed sooner than expected which would result in the ship sinking.
This image shows how the rivets would have been set up. If the Modulus of Elasticity was different due to the metal quality, this would have impacted the maximum bearing stress which means the rivets would pop and break sooner than expected.
Why did it happen?
All in all, the mechanical failures of the Titanic were somewhat inevitable, although they definitely did not help slow the process. There was a MAJOR overconfidence in the ship, and it was believed that even if there was any sort of issue with the Titanic, it could stay afloat for three days (when it only stayed afloat for three hours). The force limits on the ship were exceeded due to the collision with the iceberg, but perhaps the safety factor could have been greater than what it was.Lessons Learned
From an engineering perspective, the quality of iron and steel used nowadays has improved quite considerably, which may have prevented the sinking of the Titanic (although this is not guaranteed by any means). One of the large lessons learned was in humility and in the importance of how any engineering product is marketed. Part of the tragedy of the Titanic is how it was marketed as "unsinkable" and yet sunk on its maiden voyage. While it isn't related to the design of a product, it is still a very prevalent part of engineering as a whole and MUST be considered at all times.I've learned a lot from falling down the rabbit hole of the Titanic wreck. (As an aside, it's really interesting and worth your time to look into the SS Californian, which was within visible range of the Titanic but failed to help). One of the most important lessons as stated before is humility. While common engineering practices have come a long way, there were so many issues (both mechanical and human) during the sinking of the Titanic that all just compounded the failure to the extremes that it reached. The sinking of the Titanic caused major revamps in naval protocol and the design process of naval vessels. The structural integrity and safety mechanisms of boats were massively overhauled in the years following the wreck, for the betterment of any future events.
Resources
National Geographic CGI Titanic SimulationThis video gave me a strong understanding of the process of the wreck itself, and I was able to look at the video and notice the engineering concepts at work and the failure points as they happened.
Scientific Journal on Titanic Steel Quality
This interesting scholarly article gave me a glimpse at the maximum stresses of the steel used on the Titanic. While it didn't contribute to any of my failure notes, it did let me analyze the strength of the Titanic.
SimScale Article on the Sinking of the Titanic
This article gave me a common starting ground to look for information regarding the wreck. It linked me to both the National Geographic video as well as the information on the ruptured compartments and weak rivets.
NYT Article on the Sinking of the Titanic
This article on the sinking of the Titanic gave me more specific information on the faulty rivets, elaborating on the samples retrieved from the Titanic as well as information from the Titanics sister boats.