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Re: [SPAM] - Country Factor on AASHTO Loading for Bridges - Please Help

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Dear Iqbal,
I think it is a very good idea. I also believe that proposed Class-A-1 loading by NHA is also very similar to AASHTO truck loading as far as axle spacing and number of axles is concerned. I wish you best of luck in your work. I would be very interested in knowing the results of your research. Please also advise me of any upcoming seminars of NHA.
* My guess is that this factor would be somewhere between 1.40 - 1.60 or even higher with the current situation of overloaded trucks.
----- Original Message -----
From: CM Iqbal
Sent: Friday, October 29, 2004 10:48 PM
Subject: Re: [SPAM] - Country Factor on AASHTO Loading for Bridges - Please Help

Dear Faiz and Hamid,
    In Pakistan we are still using only Class-A and Class-AA loading along with AASHTO codes. This particular loading pertains to an age old code of 1967, therefore, it needs to be revised. Some time back I had organized a Seminar on Bridges held at National Highway Authority, most of the speakers stressed on the need for the revision of the existing code of 1967.
    During this Seminar it was stressed that instead of developing and maintaining a new Bridge Designing Code, which will be  difficult for a developing country like Pakistan, it would be rather convenient to use AASHTO codes and its loading but using a Country Factor as our bridge loading is higher than those specified by AASHTO. The examples they had given was of Dubai who are using a Country Factor of 1.25, similarly some other countries have also adopted this design procedure.
    Any how I am working on this project, where I will be designing about 20 bridges of different lengths both on AASHTO loading as well as on Class-A/ Class-AA loading keeping all other factors the same and the find out a safe Factor which will be a comparison of the two loadings. It will take me about two to three months but I will let you know about the findings. There after, we are also planning to have a Discussion Seminar where we will invite all leading bridge consultants to discuss this issue and give their recommendations. 
    No doubt you have never heard of a Country Factor, but it doesn't mean it does not exist. It is a very convenient way of designing of bridges for many countries.
CM Iqbal
----- Original Message -----
Sent: Thursday, October 28, 2004 9:18 PM
Subject: Re: [SPAM] - Country Factor on AASHTO Loading for Bridges - Please Help

Dear Iqbal & Faiz,
In Pakistan, even now Class-A and Class-AA (70 ton tank) loadings are used for the design of highway bridges. However, recently a new loading, Class-A1, has been introduced which, I believe, is still at proposal stage. Class-A vehicles are spaced at 65 ft. whereas class-A1 loading consists of closely spaced trucks. I agree that I have never heard of this country factor thing. In Pakistan,  loadings of West Pakistan Highway Code-1967 are used with AASHTO-92 and 96 codes for the design of bridges.
----- Original Message -----
From: Syed Faiz
Sent: Thursday, October 28, 2004 2:10 PM
Subject: RE: [SPAM] - Country Factor on AASHTO Loading for Bridges - Please Help

Never heard of this "country factor" thing before.
In Pakistan (and for that mattter in India and other parts of the sub-con), I believe they use Class A and
Class AA (70-Ton Tank-Track loading) for the design of bridges.
At least, this is what I knew before; although I am out-of-touch from the scene for quite some times now.
Can you update me if things have changed now?
Syed Faiz Ahmad; MEngg, MASCE
Senior Structural Engineer
Saudi Oger Ltd
P.O. Box: 1449
Saudi Arabia
Cell: +966-508-169304
-----Original Message-----
From: CM Iqbal [mailto:cmiqbal(--nospam--at)]
Sent: Monday, October 25, 2004 8:00 PM
To: seaint(--nospam--at)
Subject: [SPAM] - Country Factor on AASHTO Loading for Bridges - Please Help - Bayesian Filter detected spam

    For designing of bridges, nearly every country is adopting her own specific design loads which are normally higher those specified by AASHTO loading.  As an alternate solution to have their own specifications written, a number of countries have now adopted AASHTO Specifications for designing of bridges along with a 'Country Factor', which is a multiplier ( 1.5 to 2.5) to cater for the local enhanced loading.
    I am writing a research paper on adoption of Country Factor, Could any one please let me know such details or its source related to Country Factors being adopted by different countries.
    Specially if you are in a Middle East country which has adopted AASHTO specifications with a specific Country Factor, please let me know its details.