Closure of the launched deck on an unusual new bridge in Reunion Island has just been achieved. Helena Russell reports

A campaign to save an historic bridge over the Hudson River in the USA will come to fruition next year when the former railway bridge is planned to reopen as a dramatic river crossing for cyclists and pedestrians. Eric DeLony reports on the work so far, and what has still to be achieved

The recent introduction of European conformity marking and a technical approval process for post-tensioning kits has caused some confusion in the bridge industry. Here Marcel Poser, Markus Traute, Erik Mellier and Hans Rudolf Ganz explain the system and what it means for clients, designers and contractors.

Forensic engineering can provide in-depth understanding of bridge deterioration and failure, says Dr Jonathan Wood, but it is essential for the information to be disseminated rapidly.

Speed is not the only thing that makes the new bridge in Minneapolis special, reports Helena Russell.

Engineers building a new bridge over the Volga River in Ulyanovsk in Russia came up with some interesting solutions for lifting in the main spans. Vladimir Guryanov, Aleksandr Dankovtsev, Stanislav Pshenichnikov and Valeriy Kotov report.

To increase road capacity in the state of Queensland in Australia, the iconic Brisbane Gateway Bridge is being expanded - by building a near-duplicate alongside. Report and photographs by Adrian Greeman.

Formwork being used for construction of some parts of Brisbane’s new Gateway Bridge has been designed to be adaptable for piers and deck alike.

A maintenance inspection of cables coated with polymer paste showed promising results, eight years after it was first applied.

The French island of La Réunion, situated in the Indian Ocean, is noted for its many steep gorges; in fact it used to be thought that the island’s jagged nature made the construction of a modern road network impossible. However, in 2002, a decision was made to substantially improve the island’s coastal road network in an attempt to attract more tourism.

Construction work on one of South Korea's biggest infrastructure links is in full swing, with substructure erection of the two main bridges under way and the first units of the immersed tube tunnel in place. Don Fraser reports on progress so far

Pedestrians entering Spain's 2008 Exposition will cross a dramatic new bridges which is designed as a building and footbridge combined. Helena Russell reports

A new ‘living bridge’ over the River Shannon in the Republic of Ireland is designed to allow students at Limerick University to enjoy the natural landscape as they traverse the campus. Keith Brownlie and Conor Lavery report

Despite earlier setbacks, North America’s longest arch bridge is now making progress over the Colorado River

Manufacturers of expansion joints are putting great efforts into developing systems to cope with the world’s ever-lengthening bridge stock, say Gianni Moor and Colm O’Suilleabhain

To the south of the Indian metropolis of Mumbai, construction work is proceeding apace on the Bandra-Worli Sealink project. With its 500m-long main span and striking architectural design, the main bridge ranks as one of the most spectacular construction projects on the Indian subcontinent.

Refurbishment of a tourist railway in the Kalavrita valley has required engineers in Greece to come up with some imaginative solutions. Narrow and restricted access, steep slopes and historic structures made the contract, to replace bridge bearings and improve the seismic response of the structures on the line, particularly challenging.

Next year the scheme to build a new gateway bridge for the USA's capital city is expected to move another step forward with the completion of the environmental impact statement. The owner of the new crossing, District Department of Transportation, will also be moving forward with funding plans for the new movable bridge structure. With the alignment of the new crossing in advanced study, and four alternative designs presented to the public, there is growing excitement about the prospect of the replacement bridge.

Peter Vygodin reports on a dramatic new bridge that is proposed for the Neva Bay in St Petersburg

Authorities in the Russian sea port of St Petersburg are planning construction of a new landmark bridge to provide a route across the Neva River delta for the Western High Speed Diameter Ring Road, which is an express motorway. Tenders for the privately-financed design and construction of the project are currently being invited, with site work expected to start some time next year.

A new bridge over the River Seine in Rouen introduces an innovative concept for lifting operation. Michel Moussard reports

A large lift bridge is currently reaching completion in the city of Rouen, France, and when it opens next year it will provide the sixth crossing of the River Seine in the city. To fit with its environment, halfway between the historical city centre and the harbour, the team of engineers and architects designed a structure which combines efficiency, reliability and elegance.

A complex multi-level bridge in Saudi Arabia is designed to provide safe access for millions of pilgrims taking part in a key Islamic ritual in the city of Mina.

China's bridge capital Chongqing will open another world-record bridge later this year, reports Man-Chung Tang

Chongqing, a city with a population of 32 million people, was part of the Xichuan Province in the mid-western region of China until about ten years ago, when it became an independent city with the same rank as a province. Most of Chongqing is mountainous and intersected by several big rivers: the Yangtze and the Jialing, which divide the metropolitan area, the Wujiang River and so on. Consequently, development of the area requires the construction of many major bridges.

The Port of Los Angeles and the Port of Long Beach are separate facilities that were founded about 100 years ago in San Pedro Bay, California. Terminal Island, which is in the centre of the bay, was originally a mudflat that was expanded when shipping channels were dredged in the bay. Today, about 70% of the container terminals for the Port of Los Angeles and about 30% of the container terminals for the Port of Long Beach are located on the island. As well as container terminals there are passenger terminals, automobile terminals, dry and liquid bulk terminals and so on. Oil fields and refineries in the area mean that there are also oil terminals at the ports. More than 40% of all the shipping containers that move through the United States go through these ports, making them the two busiest ports in the United States.

Construction of the main towers is under way on the Second Geo-Geum Grand Bridge which will be part of the fixed connection of the Geo-Geum Island to the South Korean mainland. The two lane highway bridge with its total length of 2,028m is the second stage of this fixed-link project and will connect Sorok Island to Geo-Geum Island passing Dae Hwa Island. Erection of the superstructure and cables is intended to start in 2008 with completion of the whole link currently scheduled for 2010.

About 30km upstream of the busy Forth Road Bridge in Scotland, the Kincardine Bridge also struggles with rising congestion. But relief is already on the way for this ageing road bridge, and motorists on the old bridge can now see the leading edge of the incrementally-launched deck creeping slowly out across the estuary. The design and build contract for the new bridge is being carried out by Morgan Vinci, a joint venture of Morgan Est and Vinci Construction Grands Projets with consultant Benaim responsible for the detailed bridge design.

Its location on the flood plain of the Neva River means that St Petersburg has been plagued by floods since the city was founded in 1703. It is particularly prone to tidal storm surge floods originating in the Gulf of Finland. In order to protect the city, a flood protection barrier which is more than 25km long is currently being built across the estuary. But the barrier will also incorporate a major highway, which requires several bridges across the navigation channels and sluices.

Road building in Japan involves the construction of large numbers of tunnels and bridges because of its naturally mountainous terrain. This type of topography can make construction of even modestly-sized bridges a difficult, intrusive and expensive task. In an attempt to try and address these problems, engineers in Japan have been developing a new method of building composite truss bridges using suspension systems. In 2004 (Bd&e issue 37) construction of the Seiun Bridge in Yamashiro demonstrated how the steel truss and deck of a road bridge could be built on suspension cables. Once the deck was complete, the force in the cables, which were initially taken by ground anchors, were tranferred into the concrete upper and lower chords as prestressing forces. By using this construction method, it was possible to build a single-span composite truss without using temporary supports or falsework. Benefits were realised both in terms of construction cost and sustainability, requiring less excavation and minimising the environmental impact of the bridge.

As the new century dawned over Columbus, Ohio, civic leaders faced a difficult transportation challenge. Time, weather and traffic had taken their toll on one of the city's primary arteries, a multiple-span, open-spandrel concrete deck arch bridge built in 1937, degrading it to such an extent that it had to be closed. Its deteriorated condition meant that the Main Street Bridge needed replacing - and with a structure that suited the city's unique heritage and bright future.

Plans to restore a cast-iron footbridge at Balgay near Dundee in Scotland have given consultant Gifford the opportunity to make good use of laser scanning - a technology more frequently used by other engineering sectors and the film industry. Gifford has taken the result of the laser scan - a 'point cloud' of around 12 million points - and used it to build and analyse an accurate 3D model of the bridge According to technical direc

How many of today's bridge engineers would expect their structures to ever be designated as World Heritage structures? In fact, how many engineers are even aware that bridges form part of the World Heritage list maintained by Unesco? But engineers can actually play an important role in evaluating and nominating the best of the world's bridges to this distinguished list.

In order to meet World Heritage criteria, a bridge must be of outstanding universal value and must illustrate or interpret world heritage in terms of engineering, technology, material advancement, fabrication, transportation, communication, history, or culture. The two-stage nomination process is not entirely straightforward (see box) but listing can bring obvious benefits in terms of cachet and publicity, as well as the possibility of funding if necessary.

Examples of World

When it is completed in 2008, Hong Kong's 1600m-long cable-stayed Stonecutters Bridge will become one of the world's longest single-span cable-stayed bridges. The bridge, which crosses the entrance to Hong Kong harbour, will have a main span of 1018m.

In order to protect this strategic structure from seismic, wind actions and traffic braking loads, it has been designed with two sets of four 8000kN shock transmission units. During the dynamic action predicted under normal loads, these units are designed to provide a very stiff connection between the deck and the pylons. A specially-designed hydraulic circuit connects all the units installed at the same pylon and enables them to react simultaneously during the dynamic event to avoid torque effects in the bridge structure. The system is also designed to minimise the reaction from slow movements induced by the deck thermal expansion and to prevent unexpected overloads.

Some time at the end of the month, depending on water levels, a dramatic spectacle will take place during a three-day closure of the river Danube just downstream from Budapest. The 312m-long, 162m-high steel tied arch span of the new Dunaujvaros Bridge will be manoeuvred into place across the river using a system of barges, anchors and strand jacks.

The new crossing of the river will form part of the M8 motorway, which is planned to be Hungary's main east-west link connecting Austria and Romania directly through the middle of the country. From end to end the structure, which consists of two approach viaducts over the flood plain, and the central arch span, measures 1,683m, and is being built using a variety of different techniques.

Launching of the deck for the approach viaducts was completed earli

Modern strand-jacking equipment has come a long way from the units that were first used in the bridge industry more than 30 years ago. At the centre of any set up is still the 'work-horse', the strand lifting unit which can have a capacity of anything from 10t to several hundred tonnes per unit. While these units have of course been improved, the main changes in technology have been in the supporting equipment and applications. Thirty years ago the safety aspects of this new technology were the main factor for consideration and while this is still true, today's clients also make increasing demands in terms of cost, speed and more sophisticated applications.

Earlier th

A new road which will connect the towns of Saint Paul and Etang Sale on Reunion Island has to cross 100 ravines, some of which are very deep and cannot be accessed from below. Because of the unusual topography of the island, four exceptional bridges, two cut and cover tunnels, a 300m-long twin tube tunnel and 20 standard and 20 non-standard structures have to be built for the new route.

The contract for the design and construction of the bridge over the Grande Ravine, which is one of the four exceptional bridges, was awarded in 2002 to a joint venture of consultant Setec TPI and architect Alain Spielmann.

Skyscrapers and huge man-made islands are not the only infrastructure projects being planned for the Gulf region. As the states jostle for position with extensive leisure and business developments already under construction and new ones planned, proposals continue and plans are advanced for new transportation links, which range from mundane to spectacular.

Arguably the region's most ambitious and eye-catching project is the recently-revived plan to build a 23km-long road bridge over the Gulf of Aqaba, linking Saudi Arabia and Egypt. Incorporated in this sizeable link, which is being promoted by the Saudi and Egyptian governments, will be a 2.5km-long suspension bridge.

Fast and efficient tolling systems are increasingly being sought by road operators as the network of new toll highways around the world continues to expand. But choosing the right system for bridge tolling is even more important, explains Helena Russell

One of the main arguments for the construction of toll roads - apart from reducing the burden on the public purse, of course - is that it provides motorists with a choice. If drivers are willing to pay the toll, they can use well-maintained highways that are usually less congested than public roads, have fewer junctions, and generally get them from A to B in a shorter time. Once you have passed through the toll barrier, you may not have to stop again for a hundred kilometres or more, until you leave the motorway and pay your exit toll. If the route you are travelling has electronic tagging installed, and you have signed up for this service, you won't have to stop at all, the fee will simply be charged automatically to your account.

On the southern outskirts of the South Korean capital of Seoul, a brand new city is being planned. This hugely ambitious, US$12 billion development is aimed at creating a high technology international business destination that the Korean government hopes will become the major trading and commercial hub in north east Asia.

John Mitchell is a contented man. Bridge master of Clifton Suspension Bridge, he is in reflective mood in the bicentennial year of its designer's birth. Although Brunel never saw this elegant marriage of function and form completed, his fondness for the project was clear, describing as 'my first child, my darling'. Mitchell shares this passion for the structure, as have other engineers who have been fortunate enough to look after what is one of the great icons of England's south west, and one of Brunel's more enduring legacies.

The Romans may be considered the champion bridge builders of history, but the legacy of the Inca people in South America is just as significant. The secret of the Inca empire lay in its bridges; hundreds of suspended bridges were necessary to connect the 10,000 mile network of stone roads. These bridges had stone abutments and anchors on each side of the canyon, and they were suspended from massive cables of woven Ichu, a grass with hemp-like qualities. There were two top cables acting as guardrails, and two bottom cables that supported an integrated wooden deck of braided branches. Ironically, the fact that the bridges were strong enough to support the Spanish Conquistadors on their horses, actually hastened the fall of the empire.

Toledo's newest bridge has been officially christened the Veterans Glass City Skyway in honour both of those who have served their country and to celebrate the city's heritage in the glass industry.

The second of two cable-stayed bridges is just starting construction over the Neva River in St Petersburg. The same structural health monitoring system which was successfully installed on the first bridge is planned for the new crossing.

In recent years in St Petersburg, a lot of work has been going on to repair,

The cantilever is one of the world's earliest bridge forms originating in China, Tibet and Japan. Shogun's Bridge built in the 4th century AD still spans 26m over the Daiya-gawa River in Nikko, Japan. In the mid-nineteenth century, this structural bridge form was reintroduced and used extensively. But today, two of the world's oldest cantilevers are struggling to survive in the USA.

On a hot day in late September, it is difficult to understand why Vietnam's new Bai Chay Bridge is being specially designed to cope with storms and high winds. But the end of the season of good weather is fast approaching, and only a day later the precautions seem wise. A new technique of cable construction on this bridge is enabling the contractors to pack strands more tightly in the stay cables, producing the same strength cables within 20% less cross-sectional area. This will be a major boon in terms of reducing the wind loading on the structure.

Bids for construction of the new Ironton Russell Bridge over the Ohio River are due to be invited in November this year. But the designers of the crossing, which will link Ironton in Ohio with Russell in Kentucky, have had to resolve conflicting constraints in order to provide a solution that suited all the parties involved.

Precast segmental construction is now probably the most common method of construction of long or multiple span structures particularly for roads or railways. In basic terms the superstructure is broken down into a series of elemental segments - usually the full width of a structural element over a partial length. Precasting of bridge decks involves an industrialised process which allows the mass production of standardised components.

Two bridge deck overlay replacement projects that have been under way in the Netherlands this summer represent the culmination of a major research effort into solving problems with fatigue damage to steel deck bridges.

After the dramatic flooding of the Vltava River in Prague in 2002, investigations to check the condition of the city's historic Charles Bridge found damage to its foundations that required immediate attention. Now a second tranche of work is about to start, to repair the superstructure and secure its future.

Every time that Freyssinet project manager for major projects Bertrand Garin returns to Kosovo, usually about once a month, he notices new signs of regeneration. Whether it is the petrol stations that have sprung up every mile or so along the province's main roads, or the continuing proliferation of half-built houses, or the opening of a new hotel in the capital Pristina, things are now much easier than they were five years ago, he recalls.

With a total length of 2560km, the Orinoco is the longest river in Venezuela and the third longest in South America. Currently, the river is crossed by only one bridge, which is situated at Ciudad Bolivar, the capital of the state of Bolivar, in a region called Guayana.

With its span of 255m and a rise of 50m, the Tilos arch meets the mathematical criteria for the classical ratio of five; making it neither flat nor highly raised. The arch members have been designed to be extremely slender in an attempt to minimise its weight during the erection process, which involves the use of a free cantilever with temporary diagonal stays.

As the sun lowers over the highlands in central Ethiopia I survey the Joregeta Valley: Belie, my lead mason and a former artillery captain, barks orders to the crew with the tarp covering the last course of masonry for the night. Negussu, fresh out of high school and anxious for his college admission results, manages some fifty villagers and donkeys moving stone from the river up to the piers. Mebratu, the engineer, is nearby at the excavation for our next bridge directing the villagers with their picks and shovels. Richard, a volunteer from Silicon Valley, manages sand washing in the faint stream that will soon be a torrent when the summer rains arrive. I squat in the falling sunlight with my calculator and a fresh cup of Tella and make my next quantity list and schedule. This is construction work village style, and we are building bridges.

The Special Administrative Region of Macau includes not only the Macau mainland, but also the islands of Taipa and Coloane. Two bridges connect Macau and Taipa, one is the 1974 Macau-Taipa Bridge and the other is the more recent Friendship Bridge, which was built in 1994.

Engineers working to restore Kuwait's Bubiyan Bridge are reminded daily of the huge strategic importance of the link by the roar of US Air Force fighter jets. The planes fly low in pairs along the waterway before banking off towards Kuwait's neighbours on regular patrols throughout the day.

Several decades of research and development into earthquake hazards have produced sufficient knowledge to allow engineers to protect bridges from risks such as ground shaking and soil failure. But one hazard which has yet to be investigated in relation to bridges is earthquake-induced tsunamis.

The site of the Yamashiro Bridge scores highly in terms of dramatic views, but it is a contractor's nightmare when it comes to logistics. The bridge, which is currently under construction, is perched high up on the steep sides of a river valley with virtually no space for construction. The fast-flowing Dozan River far below is a popular spot for white water rafting.

US bridge engineers and highway administrators are gaining confidence in the performance of cable-stayed bridges. As a result, more and more of these elegant bridges are being built, with the number expanding rapidly over the last decade. The US inventory of 24 bridges that existed in 1992 is expected to nearly double by 2005. Information gathered from evaluating stay cable systems for nearly 25 long-span bridges worldwide, plus the instrumentation, health monitoring, and inspection of eight cable-stayed bridges in the US, have combined to create a comprehensive approach to cable-stayed bridge inspection, condition assessment, and maintenance of these aesthetically-refined structures.

Apart from world-famous structures like Brooklyn Bridge or the Golden Gate, the covered bridge is probably the highest profile type of historic bridges in the USA. America has more covered bridges - around 800 - than any other country. Despite being subject to destruction by arson and acts of God, these bridges enjoy a recognised status, being admired by ordinary citizens and engineers, and generally protected by public officials. There is a national programme to rehabilitate America's covered bridges, but the true bridge heritage at risk is the metal truss.

The Foyle Bridge is a spectacular man-made addition to the natural rugged terrain found to the north-east of Londonderry in Northern Ireland. The bridge was completed in 1984 and carries the A515 across the River Foyle; its elegant curve is enhanced by a minimum depth girder profile at the centre of the main span.

The Viaducto de Cieza, which is under construction at the moment in the north of Spain, consists of a pair of arch bridges. They are being built using a complex construction procedure that has been specially developed for this project in order to save money and time.

Despite the ongoing uncertainty surrounding the contract to build the new 'signature span' for the East Oakland Bay Bridge, construction of the skyway which forms the majority of the length of the new crossing is already considerably advanced.

Building a second connection across the Panama Canal is in itself a challenging and difficult task, but to have to build it in record time and open it exactly 90 years after the first ship, the US cargo ship 'Ancon', celebrated the first journey through the canal, carries plenty of additional symbolic importance. The magic day will be 15 August 2004, which is also a year from the date this young nation celebrated 100 years of independence.

Prospective single coat products are to be tested later this year in a study being carried out by the US Federal Highway Administration and the Connecticut Department of Transportation. Tests will be carried out on candidate materials with performance characteristics matching the 'coating performance wish list' that has been put together. Properties include slip coefficient, salt fog resistance and other weathering properties, adhesion, abrasion resistance, edge retention and so on, application criteria such as dry time to handle, temperature range for curing, sag resistance, chip resistance, cure time to measure DFT, pot life, recoat and overcoat with details of the type of tests that should be carried out and the suggested acceptance criteria.

The tale of how the first iron bridge designed by Isambard Kingdom Brunel was discovered and saved from demolition in the nick of time is the stuff of storybooks. At the centre of it is English Heritage inspector of ancient monuments for London, Steven Brindle, whose painstaking work and determination made this hugely important discovery possible.

Many bridge engineers are guilty of treating holidays as a chance to do a bit of structural sightseeing. Even if they can’t persuade their partners to build a vacation around a visit to a particular bridge, at the very least they might drive via a route that includes a particular strait crossing, or take a day trip out of their itinerary to make a pilgrimage to a world-famous suspension bridge.

Imagine you're a client looking to build a new bridge in a prominent spot. Any crossing at this location is going to be in the spotlight, and you want to make sure that the bridge gets the attention for all the right reasons. The obvious way to procure a 'landmark' bridge for this type of crossing, and one which is increasingly common, is to launch an international design competition and throw it open to all engineers and architects.

Construction of one of the most important crossings on the St Petersburg Ring Road, the Neva River cable-stayed bridge, is now well under way and due for completion in November this year. Approximately 40% of the cables had been erected when Bd&e went to press at the end of January, with 16 pairs erected on one tower, and six pairs on the second tower.

Closure of the arch on the new Svinesund Bridge between Norway and Sweden took place as Bd&e went to press. The arch, which uses high strength concrete is currently being built out from both banks of the fjord using the free cantilever method.

Almost two years into a five year construction programme, the legs of the pylons for the new Cooper River Bridge are rising from the huge ship protection islands in the middle of the waterway in Charleston, South Carolina.

One of the key aspects of the construction engineering function for cable-stayed span erection is monitoring the forces in stay cables throughout bridge construction.

One of the most high profile infrastructure casualties of the recent war in the Balkans was the ancient stone bridge in the centre of Mostar, in south-west Bosnia-Herzegovina. This structure, which was a World Heritage site, is now being rebuilt using ancient stonemasonry techniques and specialist engineers.

Roman arch structures absorbed the expansion and contraction of the bridge through tiny movements between the individual stones, but modern structures use high-tech expansion joints to serve even heavily-loaded trucks.

Engineers designing the Kwang Ahn Bridge in South Korea (Bd&e issue no 26) originally envisaged the use of roller shutter expansion joints to accommodate movement in the 5.1km long bridge. However the owner, Busan City Government, subsequently realised that modern modular expansion joints could fulfil its requirements better.

The behaviour of large scale bridges is quite different from that of standard structures. Normally, a bridge is constantly moving in a steady and predictable manner under influences such as temperature, traffic loads, and winds.

In January, the northern section of the Sgt. Aubrey Cosens VC Memorial Bridge in Latchford, Ontario suffered a partial collapse. Three suspenders, which connectc the arch and deck of the bridge, broke as two tractor trailers were crossing the bridge. The two drivers were not injured after the 180mm thick roadway dropped 2m. Officials believe the structure, first built in the 1960s, failed after one of the coldest nights of the winter at –25 degrees C caused the steel to snap.

With advances in material technology, bridge designers are able to increase the efficiency of structural components and design longer and wider spans, but these designs require innovative construction solutions. Clients, on the other hand, are imposing more and more stringent schedule milestones, forcing contractors to seek solutions that save time and money. The bridge construction industry must find 'out of the box' technical solutions for the erection of superstructures that have been specifically designed for a certain project in order to increase productivity.

The Dong Hai Bridge, otherwise known as the Eastern Ocean Bridge, will link Luchaogang, Shanghai’s new port in Nanhui County, across the sea to Yangshan Island in Shensi County, south of the Yangtze River mouth.

Installation of dampers at bridge deck level on stay cables is the most common countermeasure for increasing the structural damping of cables and reducing vibration. Until recently the most common solution was to install hydraulic or viscous dampers between the stay cable and the deck, near the anchorage.

Given that Scandinavia is a region blessed with plentiful forests, it is not surprising that wood is finding favour as a structural material for a growing number of new bridges. But while many of the projects realised so far have been built on a comparatively small scale, the latest scheme at Flisa, an hour and a half’s drive from Oslo, is claimed to be the biggest wooden bridge in the world.

Sundoya Bridge is situated in one of Norway's most scenic areas, only 100km south of the Arctic Circle. The 538m-long bridge spans Sundet, and when it is complete will provide a ferry-free road connection between Sundoya and the mainland.

Corrosion damage to ageing reinforced concrete bridge decks poses the threat of costly and disruptive repairs. New non-destructive testing technologies such as ground penetrating radar are being used to map defects at an early stage to enable timely and cost-effective repairs.

In recent years, increasingly frequent repairs have been required on the roller-shutter joints of the New Lillebaelt Bridge.

Bangladesh extends across the low lying flood plain of the Bramaputra and the Ganges basin between India and Myanmar, and is splintered by many rivers and tributaries that flow into the Bay of Bengal. Bridge building across its major rivers has been a key feature in the country's drive for better road access and economic stability. The latest in this programme is the Bhairab Bridge, now known as the UK-Bangladesh Friendship Bridge.

When Abraham Darby completed his ambitious project in 1779 to build the first cast-iron bridge in the world, he left behind no clues as to how he had achieved his success. The bridge near Telford in the UK, was the first structure to use the new material, and although there are many images of the finished bridge, there was no evidence of how it was constructed.

At first glance, the new pedestrian bridge being built over the Gave de Pau river in the south of France is just another modest cable-stayed span like hundreds of others being built all around the world.

Performing work over water has always been more difficult and expensive than performing the same work on land. And when the work is performed below water, the difficulties and cost difference can increase geometrically with the depth at which the work is performed. The key to carrying out marine construction work efficiently is to minimise work over water, and perform as much as possible on land. The use of float-in cofferdams to construct marine bridge foundations is a successful application of this principle and one of the first projects on which it was used was the Bath-Woolwich Bridge in Maine, over three years ago (Bd&e issue no 14). Caltrans recognised the advantages of this construction method and applied it to the design of the main tower foundations for the new suspension bridge across the Carquinez Strait.

A new high strength steel reinforcing bar that has just been launched in the USA is aimed at reducing the corrosion problems that can devastate bridges and other reinforced concrete infrastructure.

Over the last 50 years there have been major road building programmes in Western Europe to cope with the increasing growth in traffic. But in most countries the main motorway construction programme is now coming to an end and attention is switching to maintenance of the existing stock. Many of the bridges built in these road programmes are showing signs of deterioration after only a few decades in service, as a result of increasing loads, physical and chemical attack. By contrast highway structures in Eastern Europe tend to be older, have been neglected and are in need of major rehabilitation.

Superload brings together the highway loading programs H-load and Autoloader into a single package. Combined with the analysis suite Superstress and the Wood and Armer equations processor W-armer, Integer is able to provide a complete solution for bridge engineers whether they are involved in new works or assessment.