Tag Archives: comparative geometrics

Parameters (3) vehicle type

So far I have discussed the concept of fundamental parameters in highway geometric design (for example, here) and the fundamental parameter “road type“. This post covers the fundamental parameter “vehicle type“. Vehicle type relates directly to design vehicles – the … Continue reading

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Document on road design standards by country

An update, version 5.2, of the publication “Road design standards” (of which I am the editor) is now available. You can find a link to a free copy of the document if you visit the home page at https://roaddesignstandards.wordpress.com The … Continue reading

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Simplification of standards (3)

Other complications with standards Layout One problem with some standards is not the format – pdf or paper for example -but that you have to search backwards and forwards through many pages of the document before you find all the … Continue reading

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Abu Dhabi streets in new “global street design guide”

The US organisation NACTO is preparing a “Global Street Design Guide (GSDG)”. The NACTO project page (see here) says that this: “… will be a timely resource that will set a global baseline for designing streets and public spaces while … Continue reading

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Road geometric design – control lines

A control line is an imaginary line along a design for a new road. For example, (Ref. 2133)  says that “The horizontal and vertical elements of a road are described in terms of control lines. Control lines are lines mathematically … Continue reading

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New road classification / 1 – too many languages

This is the first of a short series of (short) posts on a new road classification.

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Uncertainty in highway design (1)

I suspect that one of the differences between engineering and science is that  science tends to claim precision, whilst engineering  involves an element of pragmatism. For example , any highway design manual which quoted friction values to 3 decimal places … Continue reading

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