7th October 2010, 11:09 PM
Unitof1 Wrote:Not sure that you would want the weight of stone baring down on piles as this might cause them to differentially subside and pull apart the stonework. The planks might have been a way to form a flat base on which to distribute the stone work. That they are ashlars would suggest that they were intended to fit/lock neatly together. Possibly there are two phases (of construction if not of use) going on with an original construction based on wooden piles followed by a consolidated stone bridge.
(I make this up as I go along)
I came across a very strange roman use of wooden piles this week. 1000m up on a mountain in Turkey, piles were densely packed to form the foundation of stone walls. The soil conditions were sound so why use a foundation method which is for unstable soil conditions? Getting back to planks, I still think they must be a squashed beams, if they were planks how thick do you think they would be 2000 years on, less than 1mm?