I am trying to design a pavement using the MEPDG method in africa. since it can be calibrated anywhere how best can i go about the methodology without the AASHTOware software for a thesis?
You may need access to software, only to model and calculate the developing stresses and strains at specific points within the pavement structure. I frequently use Bisar or Rubicon.
That being said, you can do everything by hand. The SAMDM (South African Mechanistic Design Method) is described so well in this book (free download): http://www.nra.co.za/live/click.php?u=%2Fcontent%2FSAPEM-Chapter-10-2nd-edition-2014.pdf&o=Item%2B232
If you follow that as a step-by-step guideline, you'll be fine. You can ask many questions along the way and I'll try my best to answer them.
There are hundreds of parameters involved, and to do all different calculations by hand would be tremendously strenuous if not impossible. I would suggest to use AASHTOWare trial/student version to use for research purpose which can be less expensive to get license. Best wishes!
You can calculate the stresses and strains induced by your representative truck loads and at the different temperatures using any existing free software (Kenlayer, ELSYM 5, Bisar), then use the failure model (Fatigue, rutting) to calculate the damage using Excel or any other spreadsheet software. Of course, the MEPDG software uses models to find the temperature at different depths, etc. For your case just use uniform temperatures. The same applies to the water content of the subgrade soil and untreated base materials.
Most of the people agree that the methodology of MEPDG is quite simplified and overlooks many important variables such as viscoelasticity of asphalt, 3-D contact stresses and so on. The only powerful and attractive feature of MEPDG is the fact that its distress predictions are calibrated based on climate, trafic and mixture properties and so on. Thefore, using MEPDG software for a region for which its not calibrated can likely lead to inaccurate designs and in my opinion, the study becomes accademically debatable. That being said, if you just do comparison between two things and report your findings in terms of relative differences (e.g., percentage and so on), i think it becomes more academically acceptable.
Without proper calibration, any computer program or method is as accurate as a shot in the dark. However, if you are interested in incremental pavement design, you may take a look at Universidad de Costa Rica's software, developed by Lanamme.
Check their work in this link (It is in Spanish, but Google may give an accurate translation):
http://www.lanamme.ucr.ac.cr/index.php/inicio-mp.html
They have and MEPDG-like method calibrated to their conditions. All software is free to download prior registration. Their researches frequently publish in English so that you can obtain papers about their work without the translation hassle.
You can use 3-D Move Analysis sotware which was developed based on ME pavememt design. Free downloadable from this link.
http://www.arc.unr.edu/Software.html
Respected Mohammed
The calculations cannot made by hand and the software is necessary. I recommend other software such as MnPave from Minnesota DoT.
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