Leading Specialist in Bridge Bearing Replacement
Where the condition of your existing bearings are concerned, no one is more capable, or experienced to advise you than Freyssinet, the UK’s leading bridge bearing manufacturer and specialist in bearing replacement. Freyssinet’s highly trained and experienced engineers, are available to come and complete site inspections throughout the whole of the United Kingdom and Ireland.
The services offered include identification of the bridge bearings, condition assessments, and advising on the practicalities of refurbishment, and/or bearing replacement. As part of the service, a comprehensive report is available, which would be photographically illustrated, and available in an electronic format as necessary. This allows the client to integrate our report into their own tender documentation and reports as required.
Freyssinet are the leading bearing manufacturer and experts in the fields of bearing replacement, you can be assured that your new bridge bearings and bridge bearing replacement works will be of the highest quality. Freyssinet offer the full range of bearing manufacture and bearing replacements, both elastomeric and mechanical, from their UK factory. The designs are to BS 5400, and the quality control of bearing manufacture and bearing replacement exceeds the requirements of BS EN ISO 9001.
The team of leading designers at Freyssinet are able include suitable modifications into original designs of bearing manufacture, so that later bearing replacement operations can be made easier.
The replacement of bridge bearings and other operations, such as bridge expansion joint replacement, require extremely specialised jacking and propping solutions to facilitate the work. Freyssinet can offer a wide range of appropriate techniques, no matter how demanding or challenging the situation is. Freyssinet are able to supply vertical jacks to prop up structures, and also horizontal jacks, to facilitate movement of structures.
1000 tonne capacity, hydraulic jacks are available from Freyssinet with locking collars and swivel heads. To complement these, Freyssinet can use their manufacturing expertise to add to the jack heads, elastomer and PTFE sliding surfaces. These surfaces give the jack heads the ability to accommodate a limited amount of horizontal, and vertical, structural movement.
For both permanent and temporary situations, Freyssinet also supply flat jacks up to a 1000 tonne capacity, which are able to be used in gaps of 50mm or even less. For temporary solutions, where removal of the jack will be required, the inflation would be with hydraulic oil. If the bearing is to be used in a permanent situation, such as structural lifting or bearing pre-loading, a cementitious grout may be used. Alternatively, at a later date, the grout can be transfused under load if the situation requires.
Control over the entire jacking operation, can be monitored either manually or electronically, offering extremely high levels of control. The jacks can be grouped together into complex circuits, where they can be operated either in groups, or individually as required.
If the client has specified a more conventional propping system for a temporary situation, Freyssinet’s in-house designers are well placed to accommodate this, offering big advantages in terms of cost, speed and access. Propping also eliminates the need for excavation and temporary foundations.
Whether you require experts for bearing testing, or a bearing manufacturer for a bridge bearing replacement project, Freyssinet’s are the ones you should turn to.
A14 Orwell Bridge Bearing Replacement
The A14 Orwell Bridge, completed in 1982, is situated to the South East of Ipswich, Suffolk. It is a 1.3km, eighteen span continuous twin post-tensioned concrete box girder viaduct, carrying the A14 Trunk Road over the River Orwell estuary.
The scheme, part of the Highways Agency Area 6 Framework, was the scheduled replacement of two mechanical bearings supporting the North box on Pier Line 5, along with associated temporary works to facilitate jacking of the deck and to control the potential release of stored energy within the existing bridge bearings. Pier Line 5 is approximately 35 metres high.
Freyssinet Ltd was appointed by Principle Contactor Jackson Civil Engineering to design, manufacture and install the new bearings. Jacking and monitoring of the deck was also included within Freyssinet’s scope of works.
The bridge bearing replacement works were carried out during a 52hour closure of the North Deck, carrying the Eastbound A14, over the weekend of 11th-14th February 2011.
Prior to the possession, 3no jacking systems coupled with a computerised monitoring system were installed and commissioned to enable a controlled lift of the deck. The main lifting jacks were positioned on the pier top acting to the underside of the deck with a maximum uplift capacity of 3500Tonnes.
Due to the reduced capacity of the bridge box at the jacking point, a further 2 sets of jacks were installed within the bridge box to effectively brace the box and resist the forces induced via the main lifting jacks. The sets of internal jacks used were Vertical Strut Jacks with a maximum capacity of 2240Te and Diagonal Strut Jacks with a maximum capacity of 1400Te.
Once the deck had been jacked to the required height, the existing bridge bearings were removed and replaced with 2no new mechanical sliding bearings, designed and manufactured by Freyssinet Ltd. Each bearing weighed approximately 3Tonnes and had a vertical capacity of 1600Tonnes at SLS.
The deck was handed back to the Client 2 hours ahead of schedule. Works were completed to the satisfaction of the Highways Agency and Jackson Civil Engineering, on time and within budget.
Why not learn more about Freyssinet’s bridge bearing replacement services for both repair and new structure projects?
The Forth Road Bridge
The Forth Road Bridge is one of the world’s most significant long span suspension bridges. With a main span of 1006 metres between the two towers, it was the fourth longest in the world and the longest outside the United States when it opened in 1964. In total, the structure is over 2.5 km long. A staggering 39,000 tonnes of steel and 125,000 cubic metres of concrete was used in its construction.
Freyssinet were appointed the sub contractors in Spring 2010 by Balfour Beatty to develop a hydraulic jacking and monitoring system to lift the bridge deck at each support structure on the northern and southern approach spans. Each support structure on the approaches (15 piers, 2 towers and 2 abutments) required to be lifted by 2mm whilst maintaining live traffic over the structure and the existing articulation of the deck. A complex system of vertical and horizontal jacks was installed in conjunction with a series of temporary bearings, designed and supplied by Freyssinet, to support the structure temporarily whilst the existing bridge bearings were replaced. Each support pier required 8 temporary vertical support bearings and jack stacks weighing approx 600kg each, and 4–8 horizontal jacks to control any existing locked in forces. These support points were continually monitored to record loading information during and after the jacking operation.
A computerised monitoring system was established by Freyssinet in advance, during and post jacking operation, to record, deflections, pressures and temperatures at each support structure. When the structure was lifted, the 47 year old bearings were removed using hydro demolition techniques and a system of temporary support works. The old bearings were replaced with new Freyssinet bearings; fixed rocker and sliding rocker types. Freyssinet designed the new bridge bearings to very constrictive tolerances with each replacement bearing weighing approximately 2.4 tonnes.
In addition to the bearing works, Freyssinet are contracted to install an impressed current cathodic protection (CP) system, and minor concrete repairs, to areas of the supporting structures. The overall CP system utilises: discreet anodes, titanium mesh ribbon anodes and titanium mesh anode overlay. There is over 14,000 lin m of mesh ribbon to be installed between the 19 support structures alone.
Works are due to complete in Summer 2012.
Why not learn more about Freyssinet’s bridge bearing replacement services for both repair and new structure projects?