huangyhg

titanic
the sinking of the titanic nearly a century ago can be attributed to low-grade rivets that the ship's builders used on some parts of the ill-fated liner, two experts on metals conclude in a new book.
what about the big block of ice?
i think the quote you've taken from the article is very misleading.
i have never studied the sinking of the titanic
but imho nothing could have prevented from sinking after it hit the iceberg. the article states that the revits with lower strength iron where increased in size to account for the weaker iron, thus you cant blame the manufacturer.
i am biased though as i come from n. ireland
it appears that the sub-standard rivets may have allowed greater damage... article was posted for information and any discussion. i haven't done any studies on titanic, either.
dik
from the article the material for some rivets were sub-standard but these revits where increased in size to compensate for this, therefore there were no sub-standard rivets from a strength point of view, however ductility may have been affected.
the article states that more revits should have been used at the connections, thus it was possibly more likely a design issue rather than a construction issue (cant believe i've just said that as these days when something goes wrong on a construction project first finger is usually pointed at us designers, when 9 out of 10 times its the contractors fault for not following our drawings correctly). however i would think that the design would have followed standard practice at the time thus this cant be blamed either.
therefore i conclude that neither the structural design or construction was to blame.

read the article, and to me it seems like specularion rather than proven facts that the rivets were to blame. sure the contruction/design may not have been the best, but it was industry standard, and many ships were build to that standard that did just fine.
one article i read many years ago talked about the quality of steel used to make the hull. it refered to the brittle nature of the steel due to a transition temperature which was substandard. in the cold waters of the north atlantic, it was thought that the steel became very brittle and that the impact with the iceburg cause a tear in the hull which propagated under it's own. this is what they felt was the cause with liberty ships and why the cracks propagated around the hulls.
it is ironic to think that had the captin steered into the iceburg rather than away from it, the ship would have stayed afloat.
jetmaker
the titanic story seems to be one of those never ending ones ,like the jfk assasination where every few years another theory pops up !! previous metallurgical studies showed three problems with the hull plates ;excessive grain size, excessive inclusions and high brittle transition temperature. while poor steel by todays standards it was typical in those days with the technology available...there was a sonar [iirc] study done of the plates now buried in mud that showed that instead of a large tear there were a series of small cracks due to the brittleness. the crack opening volume was calculated to have sunk the ship in the time it actually took....the wrought iron use in those days was fairly common for many things . i have a fascinating video taken in those days of a british company showing making of anchors and chains for ships of wrought iron in large part by hand !!!
i always thought it was a design flaw. the designers were so sure this was an "unsinkable" design, they cut corners. one of the bad things they did was not design the vertical bulkheads to reach up to the main deck, thus they never had a truly "compartmentalized" ship design. when the holds began to flood, the ship pitched down, and water was able to rise above the bulkheads flooding the next compartment. and so on, and so on.
"art without engineering is dreaming; engineering without art is calculating."
there's an old old saying from where i come from that says "man proposes, but god disposes"
nothing anyone can design or build is indestructible or unsinkable. titanic is another confirming example.
the titanic was built to survive any two adjacent holds being opened up, and four forward holds being opened up. the iceberg ripped a 300 foot hole through six forward holds. some experts worked out that the cross sectional area was twelve square feet. the titanic's design conditions were exceeded. the height of the bulkheads is a minor technical detail. does anybody know that the standards are today? for any given structure, you can do enough damage that it will fail.
i watched a tv show about a great lakes freighter sinking some time in the mid-sixties. the ship was built about the same time as the titanic, and a survivor attributed the sinking to the same crummy material used on the titanic. there may be another explanation.
my understanding is that there were very few structural failures of ships built around the time of the titanic. the engineers back then understood what they were doing and they understood their materials. their calculations were not as exact, so they used larger safety factors.
if there was any failure, it was the white star line. titanic's sister ship olympic rammed a royal navy cruiser shortly before titanic's launching, and it rammed a light ship off new york city some time around 1930. racing in the fog was a very bad habit, but olympic hit things littler than it was.
jhg
civeng80,
as you said;
"nothing anyone can design or build is indestructible or unsinkable. titanic is another confirming example."
very true! when i discussed this with one of my non-engineer friends, he said;
"titanic was built by professionals; noah's arc was built by amateurs."
clefcon

track the logic of the events that lead to the titanic disaster:
captain's disdain for iceberg reports; high speed thru potential ice field; too fast for effectiveness of lookouts; ice spotted too late; ineffective turn; iceberg strike; damage to ship's hull; flood water successively overrunning bulkheads; progressive sinking; broken hull; rapid sinking.
the root cause was the captain's actions leading up to the iceberg strike. the strength of the rivets is almost immaterial to the sinking. would failure by tearing of the plates be a more satisfying failure mode? hardly.

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