TOPICS
Specification
for Highway Works, Volume 1 (and the Notes for Guidance)
HAPAS
Articles and Reports
Local
Authority Websites
Motto
of the Month
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Introduction
Things are happening at a very quick pace at the
moment and we all need to keep up if we are not going to
make ourselves look foolish by quoting old information.
Do not make the mistake of thinking I am able to keep you
abreast of everything that is occurring, I will indicate
what I can, but the responsibility is yours to keep yourself up to
date.
There was an almost complete amendment of Volume
1, of the Specification for Highway Works issued in May
2001, if you have not got your copy yet you had better
order it, and the Notes for Guidance ( Volume 2 ) that
goes with it.
Many suppliers of bituminous materials now have HAPAS approval/certification for their
proprietary thin wearing course systems, ( be aware, this is not
quite the same as product approval ), more on this
subject further down the page.
And, Sector Schemes for various products and procedures
are now included in Volume 1 of the Specification for
Highway Works.
Full details of the various Sector Schemes can be
purchased from UKAS.
To find a "Publications List" containing a
summary of the schemes you will need to access (even
better download) this list (which is in .pdf format) from
their publications page.
It takes some looking to find the reference to the Sector
Schemes, but it is there if you keep searching, I could
just give you a straight link to the .pdf list, but then
you would not have to explore the UKAS website which is
well worth a browse.
You need to be up to date in all these matters or you are
going to get caught out, fortunately, at the moment,
these items are only specifically relevant to Highways
Agency funded work but as the "White Book"
tends to be a standard document in the highways
maintenance industry these issues will tend to drift
through into local work.
And, if one or two strong lobbying groups have
their way this will be sooner, rather than later.
Specification
for Highway Works, Volume 1 (and the Notes for Guidance,
Volume 2)
You really do need to have the new version (May
2001) of Volume 1, and study those sections which apply
to your work area quite thoroughly.
Let me give you just one example, Clause 803, Type 1
Sub-base, a material many in the U.K. will be familiar
with.
As I read the amended clause a contractor or supplier can
now supply you with a Clause 803 material that has 50%
recycled material in it, this can be bituminous material,
and you have to consult another table and a separate
clause to be able to verify its quality.
I am not going to pursue the implications just this one
change in the "White Book" will have, again, it
is up to you to do some work.
Let me just say I am 100% in favour of recycling
materials but I am also a profound believer in being able
to specify the materials you require for particular road
pavement and site situations, that is what highways
maintenance engineering is all about.
Note : Where ever possible
it is my opinion that the most cost effective way of
recycling bituminous material is back into fresh
bituminous material
HAPAS
Articles and Reports
I am aware many of you will be in
the same line of work as myself and therefore will have
access to the same publications as I do and you may well
have already read these articles.
However, many will be accessing this site to build up
there knowledge of highways maintenance and I like to
refer to as many documents as I can that are written by a
cross section of the industry, this way I hope engineers
and technicians will acquire a sufficient width of
knowledge to be able to make their own decisions.
The three articles/reports I would
like to bring to your attention at this time are :-
1) "HAPAS certificates for
procurement of thin surfacing"
This can be found in
"H&T" the journal of the The Institution of
Highways and Transportation, the July/August edition.
I find this an excellent and informative article, I
particularly like it because it mentions two words not
linked with HAPAS materials as often as I believe they
should be, the words are "audit" and
"recipe".
It is not possible to produce a proprietary thin
surfacing without a "recipe" in the computer at
the batch plant to produce the particular bituminous
mixture. If, you have a "recipe" for a material
it is possible to audit the material produced to see that
it complies with the formulation derived from all the
trials undertaken to arrive at the correct blend of the
"premium" priced bituminous material.
Please note I am talking "audit" testing, if
the sampling and testing indicates the material is
correct the HAPAS process will be shown to be a way of
supporting confidence in proprietary materials, if the
results are not as they should be it will show that the
HAPAS process needs further development before it is to
have the full trust of the "purchaser".
2) TRL Report 496 : Review of
protection provided by surface dressings and thin
surfacings to structural pavements
Prepared for Quality Services (Civil Engineering)
Highways Agency
Because this is a report it is able
to go into some depth on the subject, it is excellent
reading and I recommend that you try and get access to a
copy, it is not expensive ( £25:00 I think ) and can be
purchased from TRL.
You can buy it "on-line" if you visit their
website, you will find a link to their site on the "links page".
3) Thin layer surfacing systems : an
overview
This article can be found in
"Network: The Nynas Digest of Bitumen", which
is a free newsletter published by Nynas, a company that
is one of the big suppliers of bitumen to the industry.
The copy you need is Issue No.11 - Winter 2001, I believe
this is the last copy the have published.
If you cannot find a copy in the office where you work,
they are available free by visiting the Nynas website,
(you can even request back copies if they are available)
or you can ring, 0151 326 2938, ask to be put on the
mailing list because although these newsletters are
industry orientated I have found they include a lot of
straight forward technical information on bitumen and
bitumen products.
This is another excellent article on thin surfacings,
explaining the subtle differences between porous,
semi-porous and non-porous materials, and it has some
nice photographs to support the text.
Note : All the above refers
to proprietary "brand name" products that have
somehow achieved the title of "thin
surfacings", do not forget there are many bituminous mixtures that can
be laid thinly (
i.e. below 40mm. ) specified in BS 4987 and BS 594 and
they will possess very similar properties to HAPAS
approved materials, according to which material you
select.
These British Standard
(generic) materials will not be permitted for use as
wearing course on motorways and trunk roads in England,
but are still the main source of bituminous mixtures used
on the 95% ( by length ) of the highway network that is
not motorway or trunk road.
Local
Authority Websites
This site is an excellent find, many
of you may already know of it but for those of you who do
not you should give it a try.
Once on the Local
Government Web Sites access to the individual
authority sites is gained by using your mouse and
pressing on the correct outline on a map displayed on
your VDU, (quite a good geography lesson).
Many authorities have information on their sites relevant
to highways maintenance matters if you take the time to
look, as well as all the other interesting historical and
tourism stuff.
As examples of what can be found,
look for the "Cornwall Design Guide" in their
Publications List, and on the Leicestershire website look
for the "Highway Requirements for Development"
under the heading Planning and Transportation Department.
The Leicestershire information is able to be downloaded
in convenient size .pdf files, which is nice.
I am sure other local authority websites also present a
wealth of useful information to the highways maintenance
engineer, it is just waiting to be discovered.
It is unlikely you will find this type of information on
the website of a highways maintenance consultant.
Motto of the Month
"Ability
is the power of applying knowledge to practical
purposes"
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