Civil Engineering Association - Traffic-induced ground vibrations (time history data)

Traffic-induced ground vibrations

-time history data-

Friends,

I made digitalization of 4 scanned time history records. Firstly I made the digitalization for myself but I decided to share this data with you as well to help you in your research/ teaching or engineering in general. I'd be more than happy if you make some comments (good or even bad) regarding this work I made. If some of you think this job is worthless I'd be happy to know that because I plan to use those TH's in making my seminar work and some kind of research. Just please, with every comment I expect full explanation “why” and “why not”. Don't just say "this data is bad"!! It took me 6 days to make digitalization of those 4 THs', so at least you can make full comment.

Data provided here has to be used along with the article "Building vibration to traffic-induced ground motion" written by Hong Haoa, T.C. Anga, Jay Shenb that can be found here:

Code:
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or can be downloaded here:
[attachment=1144]

All the info concerning the THs’ I didn’t type here, you can find in the article!

Keywords of this post:
building, vibration, traffic-induced, ground motion, time history, ground acceleration, motorcycle, truck, bus, light vehicle

Idea:
Due to lack of this kind of data I needed badly and due to lack of equipement for doing real-time measuring of traffic-induced ground motion in my surroundings, I used some assumption and made "artificial" time histories. It's obvious that there just can't be two the same nor even two similar THs' taken on the same location and with the same traffic. Those THs' I provided for you are not "perfect" nor the same ones taken by the authors of the article but anyways now you have something for free and something you don't have to make on your own and waste your time. I believe those THs' are good for study and learning things. If you are going to use those THs' for making some serious calculations, do so at your own risk!

How it's made:
Article THs' are zoomed to 280% in Adobe reader, and the screenshots are taken. Those screenshots are copied to AutoCAD and scaled to make the TH fit the line 20 units of measure long (e.g. 20 millimeters long) - so one second equals one millimeter. THs’ (0,0) point of coordinate system was set to overlap the (0,0) of the AutoCAD just to make easier reading of the data (length of ordinates). The 20 second “long” line was divided into 400 segments. Vertical lines were drawn from each of the points defining the line segment. Those vertical lines were drawn in a way to cover the closest and highest peak of the TH. When I had all the segment points covered, I measured each of the vertical lines length and saved it into the excel spreadsheet. Each excel spreadsheet line contains 10 peeks (i.e. we have 10 columns in excel spreadsheet), thus we have 40 rows in excel spreadsheet which equals 400 points of TH. When all the peeks were entered to excel spreadsheet, I measured the absolute highest peak and two random peeks in AutoCAD and compared them to the original values provided in the article. Then I calculated the multiplier which will be used to convert data in excel spreadsheet to match the data in article. When this part of job was done all the data from excel spreadsheet was copied to some .txt file I newly created. To be sure the job was made as properly as possible; I imported the .txt file into SAP2000 to make time history function. Then I rechecked those previously random measured peeks (which matched almost perfectly). I made one more (maybe stupid) check; I took the screenshot of the SAP2000 window displaying TH and paste it to PowerPoint, cropped the screenshot so the TH is the only visible part of the screenshot. Then I copy-pasted the "original" TH screenshot used in AutoCAD to the same PowerPoint file and used option “Set transparent color” over it to remove the white color from the screenshot. I cropped the "original" screenshot, rescale it and moved over the SAPs' TH - the matching was almost perfectly. Do remember I was doing 3 time check per every 10 to 20 points entering to excel spreadsheet taken from AutoCAD just to be sure I didn't skip some of the data and to be sure I haven't made some other mistake in making the digitalization.

The "test" of aaccuracy:

Error I made when making digitalization:

Four heavy trucks TH:
[attachment=1140]
Many cars and motorcycles TH:
[attachment=1141]
One bus and one truck TH:
[attachment=1142]
Three light goods vehicles and two trucks TH:
[attachment=1143]

With regards,
Grunf