Medieval Structural Design
Medieval Structural Design
(OP)
I have always been fascinated with old medieval structures, castles in particular, but also cathedrals, churches, abbeys etc but I have always wondered how they were designed.
Was it done by rule of thumb, if so do we still know these rules? Was it trial and error? If something fell down did they just start again? or did they actually do design calculations to substantiate things?
And another thing, I wonder if they did drawings or just arrived on site and thought 'OK, that stone there, that one over there'.
I find it amazing that we were able to build such enormous structures all those years ago.
Does anyone have any ideas? If there were designs/calculations/drawings made, and they still exist I would be really interested in seeing them?
Was it done by rule of thumb, if so do we still know these rules? Was it trial and error? If something fell down did they just start again? or did they actually do design calculations to substantiate things?
And another thing, I wonder if they did drawings or just arrived on site and thought 'OK, that stone there, that one over there'.
I find it amazing that we were able to build such enormous structures all those years ago.
Does anyone have any ideas? If there were designs/calculations/drawings made, and they still exist I would be really interested in seeing them?





RE: Medieval Structural Design
RE: Medieval Structural Design
Rick Kitson MBA P.Eng
Construction Project Management
From conception to completion
www.kitsonengineering.com
RE: Medieval Structural Design
I am sure that most European castles, churches and etc. probably used some sort of trial and error. Unfortunatedly, history usually preserve the stuff that works. All the errors are usually lost (demolished by the original builder/owner since it didn't work, or nature took it down since it didn't work).
Now, the questions of drawings is interesting. We produce massive amounts of drawings in my industry for things that are much small in scope than a castle or church. I wonder what type of document control they had back then?
RE: Medieval Structural Design
Much Masonic lore is rooted in the carefully guarded knowledge of building craftsmen. This goes back hundreds (thousands?) of years.
RE: Medieval Structural Design
You might want to explore the history of the Beauvais Cathedral in France. There was a great discovery channel (or was it NOVA) show about the engineering that went into it. It is infamous for collapsing, more than once, and being rebuilt with lessons learned. I believe the story goes that the Bishop in Beauvais got in a disagreement with the french crown and the cathedral was ment to be grander than the Notre-Dame cathedral in Paris, kinda a one-ups-manship to spite the crown.
Timelord
RE: Medieval Structural Design
A lot of cathedrals in the UK have very dodgy foundations... almost to the extent of having next to none.
I seem to recall that Salisbury cathedral is built on gravel with little in the way of foundations and the ground water level is a matter of inches below the floor.
RE: Medieval Structural Design
A.
RE: Medieval Structural Design
The Vikings were pretty good at naval architecture, fer sure, man.
RE: Medieval Structural Design
One trick they probably used was to build an upside down model of the crosssection of the nave and its supports in string, and then added weights to represent the roof and so on.
By adjusting the angles and the weights (those pointy spires on top of arches and pillars aren't there just for looks) they could get the whole thing square. The line of each string then showed the thrust line through that member, and had to be kept to the middle third of the column.
I am told Gaudi used the same method, but in 3d.
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Medieval Structural Design
Cool, I wonder if it is still classed as temporary works then?
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Give me a lever long enough and a fulcrum on which to place it, and I shall move the world.
Archimedes
RE: Medieval Structural Design
RE: Medieval Structural Design
RE: Medieval Structural Design
Whether you could get to all of it, dismantle it without having to cut beams in-situ, or get any of it out without turning it to matchwood first could well be another matter.
Although 800 years old, Salisbury has a supremely efficient acoustical design - it is one of the easiest and most pleasing buildings to sing in I've ever come across. Does anyone know whether that was just down to long experience, or might there have been some clever modelling tricks there too?
A.
RE: Medieval Structural Design
I have heard the buildings in Antigua, Guatemala described as being of the "Darwinian school of architecture".
The town is prone to earthquakes and only the fit survive.
RE: Medieval Structural Design
It achieves it's acoustic performance rather more elegantly than the silver slug on Gateshead's quayside, which also claims to have excellent acoustics.
htt
Wonder if it will still be standing in 800 years? One would rather hope not!
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I don't suffer from insanity. I enjoy it...
RE: Medieval Structural Design
A.
RE: Medieval Structural Design
http://www.oldcastleshop.com/index.html
http://www.oldcastleshop.com/blick-burgtor.htm
RE: Medieval Structural Design
Dik
RE: Medieval Structural Design
Hard to be critical when it worked until big cracks started to appear in the 20th Century and a diver spent some years replacing it all section by section with concrete.
(By the way, I like the Sage a lot more than I like the tower block behind it, though I am not agreat fan of Sir Norman Foster's other "Gherkin", Reichstag dome etc.)
The keeping of secrets, a masonic code etc. is possibly the cause of more lost skills than anything else. The Romans knew how to use concrete and cement yet this was lost for centuries after the collapse of the empire.
However, lime mortar, which served in its place, has its advantages... since the core of a castles walls would be rubble and lime mortar, the lime mortar had an important advantage over the Roman materials... it acted like a jelly when struck by a stone from a catapult.
Also, and you can see this in old buildings where the foundations have sagged or the building settled, the fact that lime mortar never actually sets means that it yields and adapts where modern cements would crack and the structure fail.
Stone is/was difficult to work with the available tools yet some stone is easier to work when fresh from the quarry and still "green" i.e. with the quarry sap still in it... i.e. moisture. Once cut and errected the moisture would escape through the open air surface and the minerals dissolved in it would be carried to the surface and form a crust as the moisture evaporated. A good natural protection until the advent of modern air borne pollutants.
Its perhaps why the Towere Of London was built (faced) with Reigate sandstone which is now in trouble.
Builders could and would work to the limits of their capabilities, the available technology and the available materials.
Some cathedrals took so long to build that the advances in knowledge are evident in their structure; the transition from the norman arch and huge columns at lower levels, to the gothic pointed arch and light delicate columns and, my favourite, the flying butress... all of which indicates increasing knowledge and confidence and the greater understanding of engineering involved.
Had these buildings been built with todays philosophies, financing and fear of failures, I wonder just what sort of structures we would have inherited.
Perhaps more importantly, one wonders how much our approach today, in some fields, might not be limiting our achievments?
Today conservatism rules almost every approach, that and a focus on the bottom line.
Back then they were not driven by the same commercial objectives or financial constraints.
One wonders if they were not far more adventurous than we are today.
JMW
www.ViscoAnalyser.com
RE: Medieval Structural Design
I distinctly remember from a college lecture that the Doric-styled Greek Parthenon was built with inversely cambered columns designed to force eye-level perspective to see an aligned and falsely right angled ceiling line.
It only appears to be a true right angle, but the difference is something like a matter of feet.
I wonder if these Greek (pre-medieval) structures could have even been erected in the absence of calculations. I imagine the engineering and constructing business was impressively numbers driven even compared to modern standards.
RE: Medieval Structural Design
RE: Medieval Structural Design
Cheers
Greg Locock
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
RE: Medieval Structural Design
One should pay attention in class. I would be willing to bet he mention that he was going to be or was an author during a lecture.
Back to the subject.
In the US the History Channel has be running a series of programs on Stonemasons, Templar's, and Freemasons. The Stonemasons was so revered that they were able to roam freely all over Europe and the British Isles to work anywhere that suited their fancy, thus the original Freemasons. "Boomers" in today's vernacular.
RE: Medieval Structural Design
The books, Why Buildings Stand Up and Why Buildings Fall Down by Mario Salvadori provide some insight into the historical approach to structural design, including a discussion on the Bent Pyramid at Dahshur mentioned by Ashereng.
Cheers
NB