Brighton i360Newsletter - Issue 6 - January 6th 2015Welcome to the 6th project newsletter for the Brighton i360 and happy new year!

A momentous year! It seems hard to believe that this time last year, we were still working on raising the £46m funds and here we are 12 months later with the Brighton i360 fully funded and construction well underway on Brighton beach and off site in Holland, France and Australia.

It has been a long hard road to get us to this point. When the architects David Marks and Julia Barfield dreamt up the i360, none of us imagined we would be faced by a global financial crisis and it would take us 8 years to get to this point. But we had a shared vision (and sheer determination!) to bring this engineering wonder – the world’s tallest moving observation tower and ‘son of the London Eye’ – to reality in Brighton.

If 2014 was all about moving from

concept to reality, 2015 is about moving from the ground up into the sky - our tower will become a very real presence on the Brighton seafront this year, and we can’t wait!

A big thank you!None of this would have happened without the unwavering support of our partners. As we enter 2015, we want to give a big thank you to our landlords, the West Pier Trust, Brighton and Hove Council and the Coast to Capital LEP.

We also want to extend our thanks to our neighbours . It was great to see so many of them at our December c o m m u n i t y meeting; it can

Keep up to date with our news! If you know anyone that might enjoy our newsletter, please pass this on to them - they can sign up on our website. You can also follow us via our social media channels:

If you would like us to come and talk to your community or business group, please get in touch with our Public Liaison Officer, Ruth Chapman, at enquiries@brightoni360.co.uk.

be tough living and working next to a building site and we really appreciate their support.

Here’s to 2015!!

@thebrightoni360

Brighton-i360

Brightoni360

brightoni360.wordpress.com

Our Progress: a Focus on Flanges

The big news in December was the arrival of our flanges to the SIF factory in Southern Holland, where our tower cans were originally manufactured. This is really exciting news for all those following the progress of our build as the flanges are crucial to the design – without them there would be no way of building the i360 tower.

What is a flange?A flange is an external or internal ridge / rim that is welded onto an object so that it can attach more effectively to another. Imagine two gas pipes – you need to keep them firmly together to stop gas escaping, so you would either weld the pipes to create a seal, or weld flanges to the pipes so that they could be moved into and out of position easily, forming a pressure seal once bolted together.

Why do we use flanges?We have 17 cans for our tower and we need to keep them firmly together! The problem we have is that each one is a perfectly smooth tube with walls that are, in ratio, the thickness of a bean can. We are building from the top down, so as we lift each can we need to attach it to the one below. High strength bolts “clamp” them tightly together so that they are firmly fixed.

If they don’t need to be moved, why don’t we weld?The best way to attach each can would be to weld them together, but for a tower of this scale we face a welder’s biggest problem: moisture. Although the South East may get less rain than the rest of the country, it does get rainfall all year. It also gets some incredible winds – great news for the Rampion Wind

Farm, not so great for the welders! We also have the sea air to cope with – anyone who lives close to the coast will tell you, once the salt gets in to your metalwork, it doesn’t come out easily. The only way to build the i360 safely would be to do it indoors, which is why we are welding our flanges in a factory.

What do our flanges look like?The image to the left shows a pile of flanges ready to be welded to the cans in the background. There are 33 of them in total – 16 of the cans need one at each end but the top can only needs a flange at one end.

How are they made?Each of the 33 flanges is being made by forging a red hot single ingot of steel into a ring shape of the correct diameter. The material used in the ingot is exactly the same strength as the steel used to make the cans.

When the forging is the right shape, the steel is allowed to cool in a very controlled manner. This improves the strength and fatigue resistance of the flange.

Why did we use a factory in Spain?Because of the very precise nature of our cans, we couldn’t just forge them anywhere. The factory we used in Spain is believed to be the only factory in Europe where this operation can be carried out.

How do you ensure a good fit?

The forged flange is only approximately the cor-rect size at the first stage in the manufacturing

Delivering DampersIn the last newsletter we looked at one of the engineer’s biggest challenges - how the weather could affect the i360 and what measures could be put in place to offset the wind. This month we focus on one of the most important measures - the liquid sloshing dampers.

What is a damper?A damper is a device used to offset any vibration of the tower caused by the wind – in particular the movements caused by vortex shedding (the mini-whirlwinds created as the wind moves around the tower’s circular structure and detach).

What do the dampers do?We use what are called “liquid sloshing dampers” that are fitted inside the tower. When the wind hits the tower at a certain frequency and it begins to move, the liquid inside the dampers sloshes to one side. The uneven height of the water produces a force acting on the tower in the opposite direction to the force of the wind, stopping, or at least limiting, the vibrations.

What frequency affects the i360?It is not as simple as one frequency. There are several different natural frequencies that can affect the tower and make it vibrate. We have calculated the three lowest natural frequencies that could occur, which we call Mode1, Mode 2 and Mode 3. There are different dampers in the tower for each of the 3 frequencies.

What do the dampers look like?They are small sealed boxes – about twice the size of a tin of biscuits, made out of stainless steel and half-filled with liquid. The liquid has anti-freeze added to it to ensure that the dampers can still work on freezing cold days. The dampers are stacked on top of each other, with approximately 50 in the tower placed at three different levels, and a further 8 located in the pod.

process, and has to be machined to the exact size required. Now the flanges have arrived in Holland, we join them to the cans and then machine them in another large lathe. This gives them an extremely flat surface that is at exactly 90 degrees to the can. If we did not do this, the i360 could become the Leaning Tower of Brighton! We then measure the cans with a laser to make sure they are exactly the right size.

The integrity of the weld must be checked by Quality Control. Our QA officer from Hollandia joins the team from SIF to inspect each of the welds. The inside of the can is quite dark, so they use flashlights to make sure each weld is good.

Let’s talk bolts…Up to 72 bolts are used at each joint, spaced out evenly around the circumference, and the bolts are up to 75mm (about 3 inches) diameter. A single bolt of this size can carry a load of as much as 440 tonnes. If you want an indication of what this means, a single 75mm bolt could lift 30 double decker buses!

In total more than 1,500 flange bolts are needed at the flanges – the total weight of these bolts is about 100 tonnes. A blue whale weighs a similar amount!

What happens if a bolt malfunctions?Each bolt is galvanised (the steel bolt is submerged into a bath of molten zinc) and then wrapped in a special impregnated tape to give long term protection against corrosion. Even so, the bolts form such an important part of the tower structure that randomly selected bolts will be inspected each year. The bolts can be safely removed and replaced (one at a time, of course) if necessary during the lifetime of the tower.

What’s next?Once we have welded all the flanges, we will move the cans to Hollandia’s factory where they will have all the interior steelwork added (e.g. platforms, tow-ers, bull wheels for the cable car etc.).

The end of a year is a good time to reflect on our achievements so far. 2014 was full of positive progress for us, and although the work in the ground only started in July, behind the scenes it was non-stop!

Landmark decisions!Our first major milestone was on 6th March when Brighton and Hove City Council took the landmark decision to lend the i360 £36m.

The Council has acted as ‘middle man’ borrowing money from the Public Works Loan Board (PWLB) – a government loan pot available for major building projects with a commercial return – and have lent it to us at a higher rate. This innovative funding solution is expected to earn the Council over £1m per year in profit on the interest, providing a much needed new income stream for the Council.

Over 100 contracts were signed on 19th June with our funders and construction partners. Along with the Council loan, Eleanor Harris and her fellow directors put in £6m and the Coast to Capital LEP provided a loan of £4m.

Work commences!Our first spade hit the ground on 29th July. Local firm Dorton Group, immediately began dismantling and removing the wreckage of the ‘root end’ of the West Pier (the sea island will remain). Some of the iron columns will return in our scheme.

Our contractor, Sussex based Mackley, set to work installing our construction road on the beach, put up our hoardings and site accommodation. They then joined forces with CJ Thorne to embark on the huge challenge of rerouting the working Victorian sewer and the 12 electrical cables running beneath the site. Fortunately, we managed to reroute the cables, which power around one third of Brighton and Hove, without cutting off anyone’s electricity supply!

An international project For most people, the progress of the i360 relates to what is happening on-site. In fact most of the work is hidden from view at the moment as it is taking place off-site.

In France, the bull wheels were manufactured for the pod, allowing

it to travel smoothly up the tower, whilst in Holland we finished rolling our tower cans. In Spain, our flanges were manufactured, then shipped to Holland where they have been attached the tower cans. In Australia, the dampers have been produced.

The i360 community2014 saw us give presentations to various business and community groups in the city. We were also party to many discussions about the future of a city as a whole.

Creating a companyWe have a vision to create a sustainable and ethical business. We signed up to pay the Living Wage – the first tourism

business in the City - and also joined the Considerate Constructors scheme.

We also worked with local businesses where possible and forgied links with other tourism and event providers in the city. If you would like to partner with, or work for us, please email enquiries@brightoni360.co.uk.

2014... a Year to Remember