My thesis was about Midland novelist Robert Bage who was also a paper-mill owner. His eldest son Charles was a wine-merchant, surveyor and later a pioneer in structural iron. He designed the oldest iron-structured building in England which still stands today and is a listed building.
His father was a supporter of equal-rights, education for the poor, an end to the dowry system, an end to duelling, an end to slavery. He also took maths lessons and was close to people of the Lunar Society: Matthew Boulton, Erasmus Darwin (very close) and the Midlands’ enlightenment in general. Charles Bage, a qualified surveyor, was aware of the dangers from fire which was quite commonplace at eighteenth century mills, especially paper mills, where a careless person could bring down the whole mill. Charles Bage has his place in the history of iron-framed buildings and communicated with Thomas Telford and William Strutt (who consulted Bage).
As a time-served toolmaker myself I know a little about the properties of metals although I am not a civil engineer. Nevertheless I think I know what would be architecturally sound and what would not, and whether a building is rigidly constructed or not. The twin towers and Building 7, which all collapsed on 11th September 2001, were rigidly constructed and very strong buildings. My contention has long been that they could not have fallen in a top-down collapse, one storey impacting on another in almost freefall, without the lower structures having been compromised.
I noticed during construction that the prefabricated floor sections (before concrete was poured onto them) were stacked on top of one another. Then they were raised by cranes that were standing on the floors of the inner core.
Each of the towers had supported the weight of these upper floors for 28 years without any problem. The undamaged structure below was just as rigid as it ever had been. The arrest was inevitable when the top of each tower failed. The only question to my mind is: when the arrest would have taken place.
Steel-framed buildings are structurally stronger than wood or reinforced concrete. Welded and bolted together they are very, very strong. You can of course bring down a steel-framed building with explosives. The easiest way is to topple it because it would be extremely unlikely to fall directly down due to its rigidity. It has never happened unless you believe it happened on 9/11. Here is the demolition of a steel-framed building.
Notice how the weaker materials have been removed at the base so they do not impede the demolition and it falls in the direction the demolition experts hope. If you stop the Pet Polymer building demolition at 1:20 just before the video ends it shows the aftermath of the demolition and may give you a clue as to why experts expected to see more steel debris in the 9/11 aftermath. The bridge disaster at Tacoma Narrows is another example of the properties of structural steel. It does not give way easily.
Inside Ditherington Flax Mill (courtesy: GooseyGoo)
Something very strange happened at the World Trade Centre on that fateful day. It is why almost 3,000 architects and engineers are calling for a proper investigation. Charles Bage’s iron-framed building at Ditherington still stands after more than 200 years. Steel is stronger than iron.