On case histories of tunnel settlement
It is very much a personal opinion but I’m a big fan of case history in engineering. Our engineering instincts are important but all too often they need to be trained and case history is critically important in training our judgement and instinct.
Over the years I’ve collated a lot of case history of tunnels. Originally I kept the information in an excel spreadsheet but unfortunately that has proved to be too prone to 'improvements' being made by colleagues. Whilst this is always done with the best intention, if the improvement is not in keeping with my approach to managing the data it can cause problems and usually a loss of data. Now I keep it in an online database.
After a discussion with a colleague on Friday about tunnel settlement and volume losses I’ve exposed some of the data, a list of tunnel settlements and trough width values which you can view [here]. It’s not comprehensive, it’s not even my complete data set. It is also imperfect with data coming from a mix of public sources including scaling from graphs, but I do find it is better than nothing.
As it is my personal data source please don’t expect it to be permanently available. Feel free to use it as you wish but it is a live document so if you reference it please make sure that you include the date.