Materials Man

some more selected M 74 pics

[View with PicLens]

I went to a presentation tonight on the concrete ambassador series of four talks throughout the UK, Professor Karen Scrivener gave the talk on “cementing the future of concrete – science & sustainability” She ably demonstrated that concrete was needed and demanded as a unique material worldwide and went on to get us to the nana technology that enables them, the scientists, to tell us, the users and practitioners how a better understanding of the material and its constituents can deliver concrete with less CO2 emissions. It is the constituents that hold the key to CO2 reduction along with techniques like additives to the grinding process that reduce CO2 emissions. Download the full presentation at www.concrete.org.uk/

I am  convinced by applied advanced science in concrete technology that it will reduce CO2 emissions, but at the other end of the electron microscope the production people can assist, how? clients like Transport Scotland (TS) ignore all design rules and state a free W/C ratio of 0.4, why? well they don’t say, but let me put words in their mouth, they do not believe the free W/C ratios from proffered mix designs and the quality of supplied concrete is less than desired.

So they (TS) as ultimate buyers specify what they desire through employers requirements, which at the moment means more CO2.

My point is, the rmc  industry has really to do what they say they will do and help the nano technology to produce better sustainable concrete. Why should I have a bad day just because the batcher man is having one? I know about accreditation and I will repeat here that QSRMC is not worth the paper it is printed on. Wake up QSRMC guys and realise your future is not hiding behind a QA system, it is in producing a competitive science based product independently assessed (eg BSI) for quality.

My thanks to Helen for the champagne I won in the prize draw, the only bonus I’ll see this year !

As a PS  I note TS, are, on the Forth replacement crossing moving away from ERs for specifying their full requirements and part filling in the designers appendices, noting that the designers should adopt these. Like I have said for years, not Design and Build but Proscibe and Build.

The post on Osprey diary 7 includes some remarks about Spey bay, I was at our laboratory for the Fochabers by pass, so could visit Spey bay during spare time. The reason I had spare time was our lab was being assessed for accreditation by UKAS assessors, and I was the virtual spare person at a wedding. This, because my assistants were the builders and I was the architect, so well done Jamie and Sandy, master builders.

Everyone who has achieved UKAS accreditation knows the difficulties, so I would like to thank John Macavoy, chief materials engineer  for the M74 completion for his considerable assistance in helping us to achieve the milestone we reached on the 27th of May.

[View with PicLens]

M 74 construction aerial photos, may 2010

It cannot have escaped any drivers notice that the severe winter has caused sudden deterioration in road surfaces. The concrete section of the M90 was no exception where the fast lane was under traffic management for some weeks due to the micro surfacing  not being there any more. The micro surfacing (slurry sealing?) was a complete success as I watched it being applied with some wonderment, it did give a smoother and quieter ride, and the joints from slab to slab did not cause cracks, what was that wonder material?  I don’t know. However the repairs to these extensive areas have been done with a thin surfacing, a modified SMA, I did enquire from Ennstone who manufactured and laid it what was in it to resist the joint in the concrete pavement not reflecting through the new SMA. Kind of got the brochure answer, much modified and very expensive, but I know SBS, a liquid rubber binder was in there. I have delayed putting up this post as I wanted to see the if it worked for a few months, it has.

Well done the techys at Ennstone, if this lasts for a year, through minimum and maximum expansion and contraction, then you have the solution to resurface this whole concrete section of carriageway, that has been of tremendous value to us the tax payers, but needs resurfacing. Hence the micro resurfacing section that was done but in part the weather claimed.

I have to point out when working for Wimpey Asphalt in Hong Kong in the 90s we devised (before I arrived) a mix to replace joints on bridge approaches, the annual pavement temperature range in Hong Kong is considerable, I will guess it at 20 degrees C, but these asphaltic plug joints showed no cracking where the line markings over them did. I recall 3 litres a tonne of SBS as an additive on its own with straight run 50 pen bitumen being added.

This is what happens when engineers and asphalt technologists ignore the specification for highway works, or any other imposed spec, and come up with a solution presumably backed by PI to give client comfort. It is now acknowledged that we imported a surfacing material called SMA and modified it to give a surface texture identical with the HRA WC it replaced. This was the government doing technology, must have skid resistance which equals a macro texture of 1.5mm, it hasn’t worked, particularly on roundabouts, stressed sites and where laying conditions are compromised. If you get rid of the thick binder coating on the surface on SMAs after laying, the skid resistance is adequate with 1.0mm texture giving a much enhanced durable to fretting mix. (exactly what the Germans do from whom we copied it and modified it to make it “frettable”) This has only taken ten years for the trunk road responsible agents to learn.

Dear Transport Scotland you never have followed the HA, now you’re taking a step forward on the M90 by letting the industry provide the technical solution. Globally this isn’t new, but here a welcome change.

The post title is a book title by Joe Moran, not finished it yet but can still recommend it to you folk interested in our roads’ history. This author is not dilatory when it comes to detail, it is crammed with it. I did have to point out through his blog spot that a central reservation is a central reserve, mere pedantry I know but how often can you correct a University lecturer?

Hope he doesn’t read this as I will no doubt have made several grammatical errors.

I had a meeting today with a newish testing lab in Scotland. CET Safehouse have arrived in the small marketplace in Scotland, and  have a tool that the others do not have, Internet reporting.  An evolved system, some five years in the making, not only does it act as a an electronic booking in system but it also has the worksheets and the report sheets integral to the whole system. In CET safehouse’s system they transfer into your inbox your checked and authorised results, this means you can pick up your results as fast as they produce them. UKAS still seem to rely on your final reporting function as the paper “certificate” being produced and checked and signed.

Wake up to the electronic era UKAS!

And one day after the announcement,  Soil Mechanics have acquired from Bureau Veritas (BV) the whole of their testing labs.

Saynors to Weeks to BV to soil mechanics, a lot of  “us”  have history in those links.

And on the back of the award for the A96 project, Morrison Construction will have their own UKAS site based laboratory.

I did deliver my pavement design talk to my senior colleagues on two separate occasions this week. Fortunately my stumbling performance was politely received, my highland hosts have an imbued politeness, which contrasts with my part weggie assertiveness. (Pure dead aggression, bye the way, know what I mean?)

To the talk, my spreadsheet brings together everything I put in text, and highlights, “where’s the money”. I have set it at 80 MSA  as that would appear to be the “design” standard adopted by Transport Scotland for most trunk roads. Perhaps so, if you have the money, order the best you can.

As I mentioned before class 4 designs are far too expensive, this cost comes from the foundation, the class 4 pavement is the cheapest as it is the thinnest. So I’m not sure where the highways agency thinks a class 4 foundation will be used, perhaps I need to run a few more designs with different foundation CBRs.  All blacktop surfaced foundations are more expensive than hydraulically bound materials at 80 MSA. this should worry the blacktop boys as even the very good EME2 material does not feature as a base. I also believe I can reduce my HBM prices as I have induced cracks in  HBM foundations when I now believe I was being conservative.

Other features that emerged were discussions on what needs cracked, it seems clear that mixes with 10 N/mm2 at 7 days, laid widths more than 4.75m and all HBM bases with a blacktop surface, need induced cracking. the other item was laying tolerances, it is clear that series 700 is not up to speed with the new requirements. No negative tolerances are a particular problem and need careful thought and discussion at tender time and when subsequently placing a sub-contract. Do both pre-tender?

A adjunct to pavement design was raised by me, Transport Scotland have road compliance testing at years 3, 4 and 5, this includes the deflectograph. If this shows potential defects, then investigation follows. If your pavement suffers from debonding, it probably will show as a potential defect. It is vital therefore, to “prove” your design was built to the DMRB, to record your bond coat applications, with all the attendant spraybar and product certificates. This will be necessary till a bond test is introduced. Also have the lab that cores the pavement from the upper layers to record and photograph the whole core before any splitting is performed.

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 !!

[View with PicLens]

These sand martins have found a sand pile between two piles of crushed concrete, on the site of the M74 extension. Is this a statement of desperation for nesting sites? I believe this is the case, should not parks, national trust ground and other publicly held ground not erect artificial nest sites?

see links

http://www.rspb.org.uk/ourwork/conservation/advice/sandmartins/index.asp

http://www.users.freenetname.co.uk/~sandmartin/page2.html

Needless to say the birds have been protected by those cuddly construction chaps.

David Welsh, I know you are a busy man, but the artificial site on concrete legs would be an easy construction project using mostly spare materials. If you could place this  in the land made available near where the martins are now with client permission, how green? how good? how lasting and a precedent for others to follow.

http://www.ukmotorwayarchive.org/

I had forgotten about this site above, for those of us who have constructed a few of these it is a nice trip down memory lane. In those days the testing consultant was appointed by the client and under the control of the consulting engineer. Staff for the summer was the staff for the winter, difficult to find work for ten techs in the middle of winter. In the 70’s and up to the middle 80’s there was no computers either, so no  reports could be complied. We had to do the end of contract reports calculating standard deviations with calculators, nobody read the blooming reports after completion anyway. I am sure all the tedious work put into them is not even at a status of gathering dust somewhere. These reports would never have seen the inside of Victoria Quay.

But the memories are of sunny days, long hours and good people, life was not so fast then. A lot of the M90 Craigend team are still around, still in materials, some have wandered and got lost, David Hutton, Iain Campbell, John Anthony, the “digger” with his dingo, John Neilson, Graham ??? who was on the Bankfoot job, Ian Bonar, Bobby and Tony Greer, Dave Wylie…………..

come on Geoff , Bill, Henry, Lindsay, Gary help me out with these bloody names, of the disappeared!!

My Palestinian pal has been given his letter for his finalisation of employment, and has had his final redundancy meeting which I attended.  Bassam Haj Ibrahim (Bass or Baz) is our QA and environmental manager and a casualty of our recent round of redundancies. A man, given his Palestinian background, who needs luck now, more than ever. He has an obvious advantage in Middle East employment as Arabic is his first language, so I hope his work search in that direction goes well. Inshallah. Although retrenchment is a tool to use in times such as these, you do wonder at the staff to keep to win work and staff to keep for when work is won. As QA is a fundamental requirement with all/most contracts, who manages QA effectively without a QA manager?

I hear the usual politician blurb about spending to create jobs, well I’m in construction in Scotland and it is not happening, perhaps the statistics on national spending can as usual obfuscate the facts. The facts appear to be TS’s spending is on hold to increase the budget for the new Forth crossing, NIMBYS are blocking renewable energy contracts, in particular windfarms, and every client who can delay a project is doing so to play the “new” marketplace where survival and not margins are the theme. Banks are only lending money to suit themselves. Well capitalism rules so you can’t really argue with a client with a budget. Remember the Golden rule, he who has the gold, rules.

Anyway Bass I am sadder than you will know about your redundancy, as I am a Scottish male and reluctant to show my feelings, but if there is a God, and it seems doubtful given the golden rule and the state of the Palestinian people,  then may your God go with you.

Please keep in touch through this site, so we can all follow your next adventure in life.

Masalama

In the old Morrisons (just a bit before my time) when we were owned by the Morrison family there were two Ian Raes, one was sales and one was techy. I never knew this appellation applied to Ian Rae (techy) until a few months ago when I visited a Tarmac quarry that Morrisons used to own and I was having the crack with the guys.

Well Ian Rae (techy) hung up his boots at the end of June 09 (metaphorically), as Ian will wear them till they have holes in them, not that he is tight, it’s just to get value from them. Well anyway a good materials engineer is now on gardening leave forever, and a good time to exit as IAN 73 and HD 26/06 version 1 hit the specs to confuse and bemuse.

Not that Ian would not have understood them but there comes a point, and the EU specs do this, when you ask yourself. ” how did we build anything successfully before this EU joining”?

Ian Rae like me and others made a living from the motorway expansion in the 70’s, and we successfully incorporated ourselves in organisations that tendered, tested and build said roads.

The market place today is different and more varied, flood prevention and renewables, some new roads. But still we will miss the expertise of those who’s wide experience of materials engineering was built up in pioneering days and had a breadth to it, rather than some of  today’s materials engineers who are one dimensional to the materials section they belong to.

Ian  Rae (techy) will be missed, I especially liked to hear him espouse on place names and we both had a long term liking for Neil Munro’s  Parahandy tales.

Ah Dougie Dougie if Ian Rae waas here he would tell ye himsell

“Chust wan of Brutain’s hardy sons”, he certainly is, and long may he remain so.

I was in good time, having left Whitelee wind farm at 12.30 where for you road techies we are laying blacktop on a floating road, designed by several heads and road note 29, yes road note 29. Without fuss or hindrance got back to the m74 to travel south to Locherbie, when after junction 6 met solid traffic doing that stop starting shuffle. Radio Scotland informed me there was a breakdown on the south bound and traffic was building up, aye, right it was, 4/5 miles of it! there was several breakdowns in the hard shoulder, probable over heating as it was 28 degrees C. I was ever hopeful that having passed a breakdown the traffic would clear, not a bit of it. 40 mins of stop start and i see cones, two lanes into one, some bloody breakdown, it’s roadworks, and as I clear the jam I see the cause, bloody verge grass cutting. Now this is just stupid, how much does it cost to hold back 4/5 miles of traffic for 3 hours rather than pay the guys triple time to do it on a Sunday, they would be happy and so would the travelling public.

Job done

plus whats the point of cutting 1.5 metres of grass next to a verge?, I have seen in Englandshire motorway grass cutting at marker posts only and the like. Sensible cutting focussed on a purpose, not blind exercising of a contract that globally costs the public and private purse more than the spuriously beneficial action.