The Product...
ALC Columns - Inner Sleeve Reinforcement Technology
Passive safety explained
Passive safety in vehicle impacts
Passive safety in roadside structures
ALC Columns - Cost Effectiveness
ALC offers free best cost analysis for your area
ALC Custom Product Services
ALC Columns - Inner Sleeve Reinforcement Technology
All ALC columns have an inner sleeve which extends from above the door aperture down into the root section. This sleeve gives added strength and rigidity to the whole column, and makes it suitable for use in the most arduous conditions.
The sleeve is inserted by pneumatic means. It cannot be removed, and it cannot move within the shaft, so designed performance is maintained throughout column life. The insertion technique is “press-stressed”
The European Standard, under which columns are rated, is very precise about the type of inner sleeve technique which can be included in calculating benefits in rigidity and carrying capacity of a column. The standard says:
BS EN 40-3-3:2003 (E)
5.6.2.3.3
Calculation for reinforcement type 5 (with inner tube)“………If the fit is
not press-stress then the contribution of the inner tube shall be
disregarded.”
No alternative or substitute insertion process is recognised under BS EN 40.
The insertion technique used in all ALC columns ensures complete compliance with this standard.
Back to Top
Passive safety explained
Accidents involving a collision between a car and a lighting column are quite frequent. In 2003, the last period for which figures have been published, there were 3,768 such incidents where injury occurred. This is just the number of “one car, one lamppost” instances; there were more where column impact occurred collaterally in a more complex collision.
Of those 3,768 injury cases, 23% involved death or serious injury to vehicle occupants. You can see some statistical details by clicking accident figures
Aluminium columns offer passive safety in that the material is more energy-absorbent, so that in a collision, vehicle occupants experience slower deceleration, and consequently reduced risk of injury. ALC columns are rated against the current standard BS EN 12767, and qualify as offering enhanced safety. Ratings are determined by crash testing – you can see a video clip of an ALC column being tested by logging into our members area.
At present, passive safety roadside structures are used routinely only on motorways and trunk roads in the UK. There is a very strong case for adopting a similar strategy on urban roads, simply because a large majority of car-column collisions, and the resulting injuries, occur there.
There is a European Standard on passive safety in roadside structures – you can read about the subject in more detail by clicking BS EN 12767
Back to Top
Passive safety in vehicle impacts
For the occupants of a vehicle, collision with a lighting column can be a very serious, even a fatal event. Columns do not have “crumple zones”, and they are routinely anchored firmly in the ground. Colliding with a column therefore involves extremely rapid deceleration of the vehicle, and also its occupants, which often results in injury, and sometimes death to the occupants.
ALC columns are all constructed in aluminium, which has material properties which in themselves offer passive safety - aluminium absorbs impact energy over a longer deceleration time than either steel or concrete, the two most common materials found in lighting columns in the UK. Decelerative forces are massively reduced where collision is with an aluminium construction, and the risk of injury or death is very much reduced.
The material advantages of aluminium are enhanced even further by the unique construction of ALC products, where the integrity of the column is maintained under impact.
The rate of energy absorption available from typical column materials can be seen in the following graph:
You can read more about passive safety by clicking here
“Car into lamppost” collisions are common. You can see some statistics on this by clicking accident figures
Back to Top
Passive safety in roadside structures
BS EN 12767:2000 sets out a method of testing roadside structures, and a set of ratings against which products are qualified in terms of their capacity to offer passive safety against vehicle impact. The crash set-up is carefully prescribed to ensure consistency of testing. The sponsor of the tests determines the type of backfill and foundation for the column, so that the various planting techniques in use across all parts of Europe can all be fairly represented.
The standard ratings include expression of speed of impact, rate of energy absorption, and assessed risk of injury to vehicle occupants.
The components of the qualification are as follows:
Typically, a passive safety rating would appear in the format 100HE3.
A full list of ratings is given in tabulated form in BS EN 12767:2000. To view this table click here
Back to Top
ALC Columns - Cost Effectiveness
Aluminium columns are usually more expensive to buy than their steel counterparts, although large increases in steel material costs over the last couple of years has eroded the difference substantially.
But for the customer, the initial capital cost of an item is only a part of the full “cost of ownership”. The full “through life cost” of a product must include capital cost plus all the other items associated with its use.
Aluminium columns are lightweight and easier to handle than steel. Aluminium columns do not corrode, do not need painting, and do not need the routine testing which is applied to steel to check residual strength left after corrosion.
Aluminium columns have a very long life span, and at the end have a residual value since they can be sent for recycling.
So even leaving aside all the environmental benefits of aluminium sheer economic reality means that aluminium can, in the long term, be a cheaper option.
The full consideration of what is “best value”, looking at all cost factors, make aluminium a strong contender.
Back to Top
ALC offers free best cost analysis for your area
Best Value can be fully assessed with you, for your area or project. ALC will be happy to provide all relevant data, using our software to help you analyze all the costs associated with your area or project, and help conduct a free best value analysis with you. To set this in motion, click Best Value Analysis
Back to Top
ALC Custom Product Services
ALC have well established capabilities in the design and construction
of special products. Whether your requirement is for a simple modification
to a standard product, or an out and out special, then ALC can help not
just with the aesthetic aspects, but are also qualified to design the
mechanical characteristics so that the completed product complies with
current standards.
A custom product will commonly comprise a column and a bracket. Bracketry
can be designed to harmonise with the lantern of your choice, and we have
a substantial portfolio of completed projects to illustrate our successes.
Brackets and columns can be styled to reflect the design themes of a
surrounding area, and finished to add to the total effect.
As well as columns and brackets, a custom product may also be designed to
include a variety of other services, such as supports for seasonal floral
decorations, illuminations for festive events, power outlets, and sign
boards. All such additions have a significant effect on the mechanical
loading of the structure, and must be allowed for in the overall design of
the product. Since we supply a total product you have the assurance that
all aspects of its use have been allowed for.
In some cases, the nature of a custom product is determined more by
mechanical needs, and less by aesthetic considerations. Such cases would
for example include the extra rigidity needed in exposed locations,
special rooting features, and non-standard access door sizes.
Whatever your needs, and no matter how demanding the needs of the project,
we invite your enquiry.
To look at a gallery of completed projects involving custom products,
click here
To email your enquiry, click
here and select Custom Design as your
subject.