Demolition means more road closures
ALEADING formwork and groundwork company has supplied equipment and technical expertise to help the Mersey Gateway stay on track.
Leada Acrow is involved in the project through the company’s long-standing German-based formwork supplier MEVA.
MEVA has a partnership with Spanish company Rúbrica, which specialises in the construction of large bridge structures throughout the world and has been contracted to provide form travellers and wing travellers for the approaches of the Mersey Gateway.
Each wing traveller weighs 280 tonnes and is around 48 metres wide and 20 metres tall.
It acts as a movable concrete mould to complete the full deck A BRIDGE in Widnes is being demolished as part of the Mersey Gateway Project with road closures in the area while the work takes place.
The Desoto Road Bridge near to Stobart and the Tesco Distribution Centre is being knocked down.
A 400m section of Hutchinson Street between Wandsworth Way and Desoto Road roundabout is closed until this Saturday while the demolition is in progress. It is scheduled to re-open the following weekend.
There will be a number of signed diversions in place directing traffic to avoid the closure, but the diversions will be busy and drivers are being advised to allow extra time for journeys in the width, which, at just over 43.5m at its widest point, will carry six lanes of traffic.
The machine is fixed onto two railway tracks that sit on top of the deck section that has already been cast by a movable scaffold system.
Concrete is poured into both sides of the machine at the same time, enabling workers to cast sections of the deck.
Once the concrete has set, hydraulic jacks push the machine forward to the next position and the cycle is repeated.
Leada Acrow sales director Paul Burns said: “Due to the complexity of the formwork involved in this project, we were contacted by MEVA to help design a solution to construct the formwork on the wing traveller.
“The wing traveller is a specialist piece of equipment for helping construct cantilever bridges and approach viaducts with in situ concreting using a main structure area during the demolition works of the double span road and rail bridge.
The demolition work involves the removal of a 72m long by 32m wide section of road which used to connect traffic to the Silver Jubilee Bridge but is no longer in use.
The road bridge is six lanes wide and constructed out of a 230mm thick concrete deck supported by two large concrete abutment walls and a reinforced central wall.
The construction team will employ the same methods used to demolish the Ditton Road Bridge last year.
They will install special timber bog mats to protect the road surface and rail line before they begin the demolition works. supported by the box deck, and a bottom structure which enables concreting of the wings of the deck.
“With two wing travellers used, one for the north approach and one for the south, we designed a solution to construct the formwork which consisted of our Slimlite Soldiers and Super A-Beam with special fabricated sections to allow us to create the required shape of the concrete deck.
“Myself and Leada Acrow technical director Paul Raybone worked very closely with project engineer Javier Fernandez over a six-week period to devise a solution and supply the equipment on-time, thus allowing the construction programme to stay on track.”
Scheduled to open in the autumn, the landmark structure is a 1,000m long cable-stayed bridge, with a load-bearing weight of more than 53,000 tonnes.
Excavators will then break through the bridge deck which will be allowed to fall onto the sterile area of the timber bog mats beneath.
The 19 girders, weighing in at around 44 tonnes, and the three supporting walls will then be removed individually.
Merseylink general manager Hugh O’Connor said: “This significant piece of work will be carried out around the clock to minimise disruption.
“We only do overnight working when it is essential and we are confident that the location and any noise and light will cause minimal disruption.”
There will be no change to the main diversion routes that traffic travelling to or from the Silver
The unique design is based on a cable-stayed structure with three towers; the main bridge deck is made of reinforced concrete and the spans are supported by 146 steel cable stays attached to the three towers.
Mr Burns added: “Once complete, this structure will become recognisable as one of the most impressive looking crossings in the UK.
“Part of the service to this project involved sending one of our technical support engineers to help assist site with the erection of the system and to complete site check certificates to allow them to proceed with the concrete pours.
“This was a highly complex project and after the production of 18 drawings and the same number of design check certificates, we completed a solution to allow the pouring of a new concrete diaphragm deck on the wing traveller.” Jubilee Bridge is currently using to get to and from either Speke Road heading towards Liverpool or towards the Widnes Eastern Bypass.
The footpath which runs alongside this section of Hutchinson Street will also be closed.
A footpath diversion will be put in place via Wandsworth Way, Dock Road and Mcdermott Road to maintain access on foot to and from the area but this will be longer than the current route.
Halton Borough Council leader Rob Polhill said: “This is an essential part of the project and I’d just like to ask everyone to bear with us while these works are ongoing and to watch out for the new diversions.”