The two halves of Chernobyl’s New Safe Confinement have been joined together, a development that marks a significant milestone in sealing off Reactor 4 at the stricken site. The operation to slide the two arches together required 24 precise connections on the 28,000 tonne structure to be aligned within millimetres of each other across the full 260-metre arch span. Operation “skid back” was successfully completed within a day and work has subsequently focussed on adjusting and tightening nearly 1,000 bolts to seal the two halves together. In a statement, Vince Novak, EBRD (European Bank for Reconstruction and Development) director, Nuclear Safety said: “The construction of the New Safe Confinement steel structure is nearing completion and good progress is also being made on fitting the steel frame with the auxiliary systems and equipment essential for operation of the facility and deconstruction of reactor 4. We are confident that all work will be concluded by end-2017 as planned.” The New Safe Confinement is being constructed to seal off reactor 4, which was destroyed in the 1986 nuclear accident at Chernobyl. The 110m high steel structure – which is 165m long and has an arch span of 260m – has been designed to protect the environment from radiation releases and provide the infrastructure to support the deconstruction of the shelter and nuclear waste management operations. According to EBRD, remaining tasks include the installation of a sophisticated ventilation system which will keep the structure corrosion-free during its lifespan of 100 years, the construction of a technological building as the future control centre and fitting the arch with fully-automated cranes, tools for deconstruction and other auxiliary systems. The New Safe Confinement is being constructed by the international consortium Novarka, led by Vinci Construction and Bouygues Travaux Publics. The New Safe Confinement is being financed by the Chernobyl Shelter Fund and the EBRD.  

New technology developed by a spin-out from  the Technical University of Denmark can give insights into materials properties that were previously only available by using high-powered X-rays sourced from a synchrotron, according to its developers. The technique allows non-destructive testing of samples which are undergoing processing, all within a laboratory setting, and could be valuable for the development of lightweight metals and ceramics with applications in aerospace and power. X-ray studies are important for developing new materials, because they give information about the arrangement of atoms within the sample and how this structure is related to the material properties. However, such studies generally require the use of a synchrotron to provide the type of X-rays needed to probe the sample. Such facilities are scarce, and time needs to be booked on them to perform studies. Moreover, there is limited opportunity to study processes taking place in the sample, for example the formation of cracks in the structure, because the facilities are generally remote from the lab where the samples are made and studied. Erik Mejdal Lauridsen explains the Xnovo LabDCT system Xnovo technology, based in Køge, Denmark, has developed a module which adds onto a standard X-ray microscope — a standard piece of equipment in many modern materials laboratory — which it claims can provide comparable results to synchrotron studies for many types of sample. “In a synchrotron, we use monochromatic X-rays,” Xnovo chief executive Erik Medjal Lauridsen explained to The Engineer. “You essentially throw away 95 per cent of the energy flux, because you are producing so much flux from these high-power sources, and then use your single wavelength to produce about 2000 projections of your sample. When we thought about bringing this to a laboratory X-ray source, we had to find a way to compensate for the much smaller flux that you produce. The trick was to use every single photon that come put of the source; the entire spectrum that the source produces.” The advantages of this include providing much more information in a single image, but that information has to be processed to understand it, he added. It also means that many fewer projections are needed to extract information from the sample. “We only need a few hundred frames instead of a few thousand, so we can spend more time on each frame. A scan takes 2-20 hours, but normally 8-10 hours. Synchrotrons are optimised, so they take about half an hour. We consider eight hours a reasonable time for a lab system, because of the increased convenience.’ Xnovo has worked with optics specialist Zeiss to develop the module that attaches to the X-ray microscope (Zeiss manufactures this equipment), but the company’s main expertise lies in the algorithms to decipher the X-ray diffraction patterns, Lauridsen said. “We started by developing these algorithms for the synchrotron, and that experience helped us to develop the software for the lab system. During the processing we figure out what X-ray energy the different diffraction signals correspond to, which effectively separates out all the diferent X-ray frequencies.” The processing system is also contsined within the module. The grain size in the sample is limited, Lauridsen said. “The smallest size we have proven is of the order of 20micron, we could go smaller but we’d have to expose for longer. There the synchrotron has an advantage; it can go down to 4-5micron; but most of the experiments at a synchrotron are in the 30-100micron grain scale. Officially, we recommend 40micron grain sizes.” The LabDCT system allows researchers to look at how structures develop and deform over time in 3D The system, which is called LabDCT (diffraction crystalline tomography), and works with Xnovo’s 3D Grainmapper software, will be particularly useful for subjects undergoing change. ‘If you’re annealing a sample, you can easily look at it at different stages of the process and see how crystals are forming, without having to destroy the sample; that can be valuable when you need a specific alignment of crystals for specific properties.” Lauridsen said. “If you’re interested in failure mechanisms, with a synchrotron you haven’t been able to correlate the crack propagation to the surrounding microstructure. You can look at crack propagation, by initiating a crack and looking at how it moves through the sample; but one big advantage here is that the system is 3D, so it also gives information on the material surrounding the crack. This is valuable, because to stop a crack propagating, you need control of the surrounding structure. Prof Philip Withers of the University of Manchester, who works in fields including metal matrix composites and welding of aluminium, nickel and titanium has been testing the system and is enthusiastic about its potential. “The unique capabilities of the  module and the software will definitely help to accelerate our research,” he said. “It can significantly contribute  to a better understanding and optimisation of materials within a large range of industries and sciences.”

A rail consortium funded by the Engineering and Physical Sciences Research Council (EPSRC) has highlighted several ways in which the UK’s track infrastructure could be improved. Source: University of Southampton Engineers investigating ballast migration. The £3.1m research project, entitled “Railway Track for the 21st Century”, took place over five years. It involved a consortium led by the University of Southampton, alongside the Universities of Birmingham and Nottingham plus industry partners who provided additional financial support. Using computer modelling as well as on-train and trackside measurement, the consortium investigated the forces that railway track is subjected to, coming up with proposals to mitigate against some of the most significant problems. It concluded that more effective management of lineside vegetation could help manage water content and improve stability, while better risk assessment of earthworks would reduce the risks of trains encountering landslides during periods of high rainfall. Piles driven into banks of land to stabilise slopes could further lower the risks of landslides, and a wider range of grain size supporting the track could help reduce stress and ease maintenance requirements. Source: University of Southampton Discrete element model of ballast and sleeper interface. “Trains have changed hugely over the last few decades, but the track and earthworks they run on are substantially the same as a century ago,” said Prof William Powrie, University of Southampton. “Increases in the speed and weight of trains are putting our rail infrastructure under growing pressure, while increases in service frequency are reducing maintenance windows. The changes we’ve explored offer ways to help maintain and upgrade the infrastructure for the 21st century.” According to the consortium, a slope stabilisation project in London has already achieved £1.5m in savings, shaving four months off the completion time. It is estimated that savings of between £13m and £20m can be made from improved design based on the research. Source: University of Southampton Scale track model tests for noise radiation and absorption. “This is an excellent example of how research aligned to government transport policy produces significant benefits, in this case for the railways and passengers,” said Kedar Pandya, head of engineering at EPSRC. EPSRC will now provide the bulk of the funding for the £8.2m follow on project, “Track for the Future”, which will take place over the next five years. The same consortium will undertake the research, joined by Huddersfield University. “Our work has shed more light on the many complex factors and mechanisms that determine how railway track behaves,” Prof Powrie said in a statement. “Our conclusions are equally applicable to the UK’s existing rail network and to the high-speed railways of tomorrow.”

Smart motorways programme director says contractors that fail to collaborate and share knowledge while working on its £1.5bn schemes will not benefit from its ‘everybody wins’ incentive scheme

The multi-million pound redevelopment of Waterloo train station could begin as early as October after the station submitted a planning application to local authorities.

The government has green-lit the construction of two new gas-fired power stations worth a combined £400m.

HS2 has begun the recruitment process for members of its design panel.

Origami-inspired folding bridge could aid disaster relief Japanese engineer Dr Ichiro Ario has designed a new mobile bridge based on the principles of origami, which could speed up emergency relief to cut-off areas following natural disasters. Source: Hiroshima University, Japan Construction Method and Machinery Research Institute, Hoshikei-kinzoku People walked on the completed MB over the Hongo river in Fukuyama City at its first construction test. The Mobile Bridge Version 4.0 (MB4.0) can fit in a car trailer, and unfolds in a scissor-like fashion to span small rivers and ravines. Its first construction test took place last month over the Hongo River in Fukuyama City, near Hiroshima in southwest Japan. “From this test of a new bridge concept, the next generation of bridge technology starts on a new stage in the field of bridge engineering,” said Dr Ario, who is assistant professor at the Institute of Engineering, Hiroshima University. “It is possible to use a real deployable and smart bridge with a scissor-type bridge system using this structural theory.” From arrival on site, MB4.0 takes approximately one hour to deploy, with the actual extension time taking just five minutes. It is claimed that the patented scissor mechanism outperforms the older block assembly method of construction, making MB4.0 “the world’s lightest, fastest, largest, strongest and lightest expanding temporary bridge.” Source: Hiroshima University, Japan Construction Method and Machinery Research Institute, Hoshikei-kinzoku The new technology uses a scissor-type mechanism, enabling rapid bridge construction. No foundation construction or crane operations are required to deploy the bridge, and it is hoped that its speed and flexibility could lead to faster relief reaching areas in need following natural disasters such as earthquakes, floods, tsunamis and landslides. Dr Ario believes MB4.0 could also have other applications, such as providing structural support to existing bridges in need of repair, or as an alternative crossing where a bridge is closed for maintenance. “I will further promote the development and evolution of MB4.0 in the future.,” he said. “Making MB stronger, longer, lighter, more compact, and quicker to set up will promote the development of infrastructure construction technology in general.”  

Skanska UK’s operating margin dipped from 3.1 per cent to 2.4 per cent year-on-year in H1 2015, but the contractor will recruit 1,000 staff to deliver major projects as its order book swells.

Network Rail is set to spend up to £20m on an overhaul of its headquarters at Waterloo station.