The impact of the proposed congestion charge for London, UK, which comes into effect on 17th February 2003, on construction firms that operate in the capital is discussed. Hauliers and the construction supply chain are not happy about the charge and are likely to pass the cost on to clients. However, main contractors have expressed little concern about the charge. Spokesmen for Skanska and Bovis Lend Lease were not expecting the charge to have an immediate effect on their businesses. The Construction Confederation expects to talk to TfL about how the impact can be lessened. A potential option for those seeking to avoid the congestion charge would be for fleet operators to adapt their trucks to use alternative fuels.
This article describes a joint venture project to build a bypass road in the UK which made use of environment-friendly measures to reduce waste in the road construction. A cut-and-fill strategy was developed to deal with excess earth, using it to create bunds to reduce work and road noise, and as back-fill for bridges, underpasses and culverts. Lime stabilisation reduced the need to import stone aggregate. Use of on-site material reduced traffic movements. Another method of easing site congestion was to create a temporary haul road through the site. The contractors were able to fulfil sustainable design demanded by the UK Highways Agency. Other measures include changing road gradients to reduce tree felling, and habitat creation for displaced wildlife. Using these measures has not slowed down the project.
The route of the Egnatia road project across northern Greece requires the construction of 75 tunnels and 45 km of bridges. The bridges include the Metsovitikos suspension bridge and the Votonossi balanced cantilever box girder bridge. Nine vertical axis trunk roads will link into the route. Egnatia Odos was set up by the Greek government to take over the management and speed up construction. Project management firm Brown and Root won a Greek government contact in 1995 to introduce international experience into the team. A new system of design guidelines was created. A separate design and bidding contracting system was introduced. The project was divided into western, eastern and central sections, each with an independent construction manager and three international consortia. Environmental guidelines were introduced to minimise the impact of the highway on the countryside.
This article investigates why motorway gantry structures in the UK are at least #20,000 more expensive than those in France. Gantries and cantilever signs are usually much lighter structures in continental Europe than in the UK. When portal gantry signs were first introduced on British motorways, they were made of steel or concrete, and cost about #100,000, but their signalling and surveillance equipment cost only #15,000 to #60,000. The Telematics Group of the Highways Agency (HA) drafted revisions to existing design standards to encourage light-weight construction, faster erection techniques, and easier maintenance. It also suggested using cantilever gantries mounted on the road verge, which are easy to access and much cheaper than a portal frame gantry. However, the cost difference between Britain and France is still large, despite the HA's issue of BD 51/98 in 1998. J Wallsgrove of the HA, who was responsible for drafting BD 51/98, explains that the cost is higher in the UK, because its gantries are designed to reduce the risk that they will fall on the road after being hit by a heavy vehicle. This risk is more in the UK than in France, because of denser traffic on British motorways. The HA is now studying three innovative gantry designs by British companies, in an attempt to reduce the cost of safe gantries.
This article describes the trial use of construction management (CM) in the UK. The trend is developing towards framework agreements covering large parts of the country and combining large quantities of minor works, which the Highways Authority believes will enable better co-ordination, continuous improvement and lower costs. CM includes the contractor at the design stage and includes partnering, currently favoured by the government. The trial was designed to allow the Highways Authority to exercise control over the firms used, raising quality, and to bring design and construction closer together for best value for money and minimum delays to road users. Contractors and suppliers found it attractive to have the government as direct client. Selection was based more on quality issues than on cost. A virtual board was set up to run the framework, which plays an important role in allocating work and measuring success. So far the project seems to be succeeding, but further performance assessment will be necessary.
The UK Government says that it wishes the private sector to adopt sustainable development and construction. It is trying to persuade the industry that sustainable construction involves competitiveness, survival, corporate responsibility, and enlightened self-interest. This article discusses what 'sustainable' means in this context, and how far it makes good business sense. The construction industry is doing much to promote sustainability, but there is little understanding there of what needs to be done, what it will cost, and what benefits it will bring. It was soon realised that economic and social issues should play a key part, while defence of the environment is the central objective. The industry has emphasised economic sustainability. The Construction Confederation has set up the Sustainable Construction Focus Group to provide input to Government thinking. The Group has suggested developing a sustainability culture in 13 areas, including building design, energy, pollution and waste prevention, and relating land use to transport. Several contractors have attempted to introduce comprehensive environmental management systems, but it is hard to develop a business case for the social aspects of sustainability. Whole-life costing has become a powerful incentive for economically more sustainable building.
About 2500 days after construction began on the 5.5km long M11 Link Road near London, the first few vehicles began to move slowly along one lane of its first section. The whole project is now two years behind schedule and its cost has risen by over 200% to #380M. The Highways Agency (HA) claims that the road will reduce journey times by up to an hour at peak times and save 100 accidents per year on local roads. Since work began in September 1993, there have been many problems. Firstly, both local and national road protesters succeeded in halting the project and also turned the tide of public opinion against road builders. Credible arguments have been presented both for and against further road construction projects in the UK. Other problems, which caused delays and increased costs, included services diversions and additions, and delays to two of the contracts due to new public spending constraints.
Over the next three years, the UK Government is hoping that Private Finance Initiative (PFI) deals totalling #11 billion will be signed. By early March, Sir Malcolm Bates is due to submit the second part of his review of the PFI to Alan Milburn, the Chief Secretary to the Treasury. His report will suggest ways of streamlining the PFI process. Among the ideas being considered are: (1) a proposal to set up a unit of top PFI experts who will negotiate with contractors before seeing the funding institutions; and (2) establishing a government investment bank to buy equity stakes in problematic PFI projects. However, both ideas have received cautious or hostile comments from some industry leaders. This article quotes from a wide selection of these and other comments. Some of the leaders wish to speed up the PFI process and reduce the present very high cost of bidding. Some suggest various other ways of improving the PFI process.
This article investigates the claim that hydraulic lime mortar is now as workable as cement mortar, and is better for many applications. Cement mortars and cement renders have dominated the British building construction and repair market for nearly a century, because of their many favourable properties. However, in recent years, more and more architects and conservationists have begun to question the suitability of cement mortar repairs for historic buildings. J Allen of consulting engineering company Ellis & Moore points out that one disadvantage of cement mortar is its brittleness. Because this causes a risk of cracking in many buildings, he advocates a weaker bonding material that is easy to handle, workable, able to absorb small amounts of masonry movements without cracking, allows evaporation of entrapped moisture, and encourages the construction of monolithically built brick walls without expansion joints. He claims that a modern hydraulic lime mortar, which has been produced in the UK since 1994, would be the best engineering material for many building applications. It is also environmentally friendly. The key question is how much lime mortar would cost if it replaced cement mortar. Its cost per cubic m is about #82, compared with about #30 for a cement mortar; even so, its use may often be justified.
The article outlines some of the latest developments in road maintenance techniques and materials. Cooperation between highways authorities, research organisations, and specialist contractors is stimulating valuable developments in road maintenance in the UK. The Highways Agency and County Surveyors Society Network are jointly developing a system for materials approval that extends design to approval for use. One of the most significant recent asphalt surfacing developments has been the introduction of thin surfacing to the range of wearing course materials. The two types of thin surfacing available in the UK are UL-M and Safepave. Other recent wearing course materials include: (1) Stone Mastic Asphalt, a binder-rich mastic designed to fill the void of a coarse aggregate skeleton; (2) micro-surfacing, a thin durable wearing course; and (3) permanent cold-lay surfacing materials for roads and footways. Developments for lower pavement layers include Foamix, a foamed bitumen product, and porous asphalt. Many of these developments rely on polymer-modified bitumens and on development of binders such as Multiphalte. There have also been improved surface dressings, anti-skid materials and materials for concrete and blacktop repair.
The article examines the prospects for expenditure on roads by local authorities in the UK, and predicts what work will be available in this sector. The Department of Transport (DoT) continues to allocate Transport Supplementary Grant money (TSG) for: (1) bridgeworks; (2) structural maintenance of certain roads; and (3) safety schemes. The UK's county and metropolitan authorities are struggling to come to terms with an overall reduction in funds. Highways authorities are now required to treat structural repairs of all their principal roads as capital expenditure. Thus there have been warnings that funds will be shifted to main roads, at the expense of lower class or unclassified roads. The Association of Metropolitan Authorities has two principal concerns: (1) their total allocation of funds for roads is too low; and (2) maintenance on non-principal roads is suffering. The latter effect is due to a combination of cuts in capital spending and the slower than usual rise in Standard Spending Assessments for road maintenance. The Government has also been reducing TSGs and substituting borrowing approvals, which could in practice mean further loss of money. An area of controversy is the high expense of additional bridge works, to meet the European requirement to carry 40t lorries by 1 January 1999.
The article examines the prospects for expenditure on roads by local authorities in the UK, and predicts what work will be available in this sector. The Department of Transport (DoT) continues to allocate Transport Supplementary Grant money (TSG) for: (1) bridgeworks; (2) structural maintenance of certain roads; and (3) safety schemes. The UK's county and metropolitan authorities are struggling to come to terms with an overall reduction in funds. Highways authorities are now required to treat structural repairs of all their principal roads as capital expenditure. Thus there have been warnings that funds will be shifted to main roads, at the expense of lower class or unclassified roads. The Association of Metropolitan Authorities has two principal concerns: (1) their total allocation of funds for roads is too low; and (2) maintenance on non-principal roads is suffering. The latter effect is due to a combination of cuts in capital spending and the slower than usual rise in Standard Spending Assessments for road maintenance. The Government has also been reducing TSGs and substituting borrowing approvals, which could in practice mean further loss of money. An area of controversy is the high expense of additional bridge works, to meet the European requirement to carry 40t lorries by 1 January 1999.
This special feature focusses on progress in two major tunnelling projects in London (the tunnels associated with the Jubilee Line Extension and the Heathrow Express Line), and also covers a number of developments in UK tunnelling and in drilling and tunnelling machinery.
This article examines the advantages of whole-life costing, which could revolutionise road maintenance in the UK. The Transport Research Laboratory (TRL) is developing a new road maintenance whole-life cost model for the UK's Highways Agency. TRL's model is expected to be applied for the first time in 1996, when whole-life costing is likely to make a major contribution during the next few years. The Highways Agency intends to apply whole-life costing to all its contracts eventually, so that contractors should consider applying it now. In 1996, the Agency will provide 510 million pounds for capital expenditure on maintenance work, of which 360 million will be for carriageway work and 150 million for bridge work. The bridge maintenance programme aims to: (1) maintain bridges as they are; (2) upgrade structures by improving parapet rails, etc.; and (3) strengthen structures, especially where they must carry heavier lorries. The Agency's drive to improve maintenance techniques and technology will have many applications to bridges. Carriageway design is also improving continually. Maintenance technologies seem likely to progress rapidly with the introduction of Design Build Finance and Operate (DBFO) road contracts.
The article describes the recent use of porous asphalt surfacing with modified binders on two heavily trafficked trunk roads in southern England. In both cases this type of surfacing was chosen to reduce noise and spray and needed to be laid in one single quick operation. A polymer modified binder was chosen because its improved viscosity characteristics enable a higher content to be used to ensure maximum durability of the surfacing. Their performance properties have enabled porous asphalt to be applied in many situations in Europe but widespread use has not yet occurred in the United Kingdom. In Cornwall the wearing course was laid over a hot rolled asphalt base course using a vibrating roller. Porous asphalt contains voids in the structure and requires regular cleaning. A specialised machine has been developed in which a combination of high pressure jets, suction units and brushes clean accumulated dirt from the inner 2m channels on both sides of the road. Cleaning action of the tyres was found to remove accumulated detritus towards the sides of the road. It is possible that the enhanced performance of porous asphalt with polymer modified binders will enable it to be used to overlay concrete motorways.
This article describes how the excavations of the Channel Tunnel were carried out. Most of the tunnel was drilled through Lower Chalk Marl, a very favourable tunnelling rock, which is relatively impermeable, has moderate strength, and is highly self-supporting. From the start, there was a strong pressure to finish the excavation within its 60-month civil construction programme. To remain on schedule, the work had to progress from as many points of attack as possible. From end to end, the 50.5km long tunnel has 151.5km of tunnelling, ranging from 4.8m internal diameter for the central service tunnel to 7.6m internal diameter for both the running tunnels. Additional excavations included: (1) two large undersea crossover structures; (2) three large complex undersea pumping stations; and (3) many cross tunnels and overhead ducts. 147km of tunnelling was excavated by 11 full-face tunnel boring machines, and lined with a one-shell segmental lining largely of high-strength precast concrete. The UK tunnellers were able to advance at up to 1000m per month per machine, but geological conditions were more difficult on the French side.
The author discusses methods of bridge widening using a steel and composite method to construct clear spans of up to 45m resulting in minimum conflict with the road user. The three options open for the arrangement of the new carriageway are known as symmetric, asymmetric and parallel widening. The differences are in the new land required to extend the carriageway, whether a narrow strip on each side, or just sufficient width to one side or a wider strip to allow for lateral displacement. In the case of parallel widening, one carriageway is built on new ground, and a strip of former carriageway becomes a soft verge or landscape area. There is reduced conflict between construction work on the substructures and traffic with this method, but twin spans are required with a new intermediate support close to an existing hard shoulder. A further hard shoulder is paved over the existing central reserve containing drainage and services. Provisions for future changes without reconstruction are being built into the designs to avoid the need to demolish bridges of age less than 30 years, as is presently experienced in some cases.
This article describes the construction of a new cross-city rail link in Birmingham, England, which will ease congestion at New Street main line station, and renew some of the city's most neglected areas. The link is funded by Centro, the West Midlands Passenger Transport Executive. It starts at Snow Hill, a former main line station, and runs 6.4km along the route of the old Great Western Railway through Birmingham, which was closed over 20 years ago. Its neglect since then unfortunately means that most of the 42 structures along the route will need major repairs and sometimes demolition and replacement. Centro has appointed British Rail Regional Railways as project manager, and split the work into four main contracts. Trafalgar House is contractor for the largest, for U7.7 million general civil engineering works. Work is at present being concentrated on the three new stations, with contracts for Amec, Kier and Mowlem of total value U7.6 million. The most demanding job is the construction of Galton Bridge Station, whose building is on a steep natural sand embankment, lining a massive man-made valley.
This article describes the environmental, aesthetic and other advantages of steel composite bridges, which are well placed to win a large share of a major expansion in the UK's road bridge market. They are especially competitive, because of their speed of erection, cost- effectiveness, and resistance to bad weather. A 1989 report on the performance of concrete bridges, by G. Maunsell and Partners, challenged the previously held view that steel bridges require more maintenance than concrete bridges. In fact, their maintenance is much more straightforward and predictable. Steel also has many other advantages, including: (1) low superstructure weight; (2) light units for erection; (3) simple site joints; (4) prefabrication; (5) low construction depth; (6) scope for continuous spans; (7) self-support during construction. These advantages also allow a slender and improved appearance. A new book by Iles,G called Replacement Steel Bridges for Motorway Widening, shows that steel technology is fast and flexible enough to allow girders to span a whole carriageway to be lifted overnight. In addition to better site construction methods, steel offers other advantages, in materials, welding technology, and corrosion protection systems, including a high build coating for steel that could last at least 20 years.
This article explains why very little road material is recycled in the UK, and advocates a more adventurous approach. Any recycling technique requires political will and the right economic climate for its application. There are signs that the political will is changing in the UK, but investment in recycling plant is expensive, and some hope of pay-back is required to promote that investment. Many of the techniques are tried and tested but grossly underused. If the full potential of recycling in the UK is to be realised, a more adventurous outlook in both national and local government authorities is needed. Recycling has become much more effective during the last decade, due to the development of sophisticated cold planing or milling machines that grind away existing road surface up to 300mm deep in one pass, pulverising the pavement. Most of the material planed off thus is currently reused. The methods currently used for recycling are: (1) incorporation of old bituminous material into virgin material in a static or mobile coating plant; (2) hot or cold in situ recycling by specialised machinery on the roadway. The former method is used much more often, at least in the USA and the European Community. The two hot in-place methods are Repave and Remix.
