I did a talk to our graduates recently on pavement design with a construction director, I did the technical bit he did the money / risks bit. Directors don't get to be directors in a LTD company without merit. For those of you mentally compiling a list of  directors without merit,  just ask yourself if they were good for the company, ie made money? So there are certain learning opportunities watching a director who has had training and experience that I will never have. It was a complete focus on "where's the money?" " and how can you lose it?" A money risk workshop. Although I am never oblivious to money, it  can be a blinkered vision when you  concentrate on the technical bit, consultant pavement designers take heed!! for what I am about to reveal may sound counter intuitive. So when instructed to do a similar talk to senior staff I decided to take it all of it on board myself, and what I have completed (but not yet delivered) was an introduction to the design principals followed by a lengthy exercise on IAN 73 and HD 26. Now the exercise I speak of is a spreadsheet where teams will fill in the thicknesses from the design charts in IAN 73 and HD 26 for a MSA of 80, for various CBR formations,  and discussion will follow. I have Scottish market prices on the spreadsheet. This reveals certain outputs: performance designs are more economical than restricted. HBM bases are more economical than blacktop bases. The cost of the whole foundation plus pavement has various drivers, but the foundation costs predominate, despite them being around a fifth of the whole pavement + foundation cost. This means  the choice of pavement , ie cheapest with risk analysis applied, should mean that HBM  and performance design will predominate and class 3 and class 4 foundations are far too expensive. This has singular outcomes particularly if oil/bitumen prices soar, which does affect HBMs cost, but not to the same extent as blacktop. I did ask HA if a economical appraisal had been conducted and the answer  was no, but I have read that IAN 73 and HA 26/06 have been subject to an economical appraisal. Well if my spreadsheet is correct then there are two (50% of the available performance designs) that will never be used !!

Leave a Reply

Allowed tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

© 2017 Materials Man - All Rights Reserved

Perth Web Design - Free Web Host