The high-speed rail project in Taiwan to link the capital Taipei with its second city Kaohsiung, 345 km to the south, is the largest running infrastructure project in the world with an estimated total cost of US$16bn (£10.6bn).
Hyder Consulting is the lead designer for two contracts covering 45km of the northern part of the route, and the independent checking engineer for another contract further south.
Aside from its sheer volume, the project presents an unusual engineering challenge in that all structures and earthworks must be able to support the different types of stresses caused by both the 350km/h high speed trains and Taiwan's frequent earthquakes.
These demands have opposing engineering requirements: the structures must be stiff enough to withstand vibrations from the high speed trains but not so stiff as to suffer damage from seismic waves.
The dense population and terrain make building conditions along the alignment difficult, requiring much of the route to be carried on viaduct or in tunnels. Accordingly, some 13km of the Hyder designed route will consist of simply supported viaducts and bridges, about 15km in cut and cover and mined tunnels, and 16km in cuts or on embankments.
The line is being built to withstand seismic waves using the capacity design approach. In viaducts this is achieved by designing the base of the columns to develop plastic hinges during a severe earthquake - the base is chosen to facilitate access for repair after earthquake damage.
The arrangement of reinforcement bars in the plastic hinges is detailed so that they can absorb energy by deforming in a predictable and ductile manner while maintaining overall integrity of the column. The rest of the column is considerably stronger to centre all deformation at the plastic hinges using so-called overstrength design. Consequently the hinges will dissipate seismic waves above a set threshold and limit excess energy travelling up the column.
This ensures the structure remains stable during an earthquake.
Recruitment agency Vital Resources will be at the Infrarail exhibition next week for the first time, promoting its services to the industry. The company has a search and selection division that places executives in engineering and technology.
Tel: (0161) 794 3344
Lightening the road load
Aggregate Industries' strategy of using the rail network to serve urban markets is helping direct heavy lorries off congested roads, the company says.
A railhead linked directly to the company's quarry network will feed the latest £4M Super Urban Plant (SU) in north west London.
'Rail now stands as the best way of getting our materials into the region and there are significant environmental and economic benefits, ' says AI business development manager for the south east, Richard Hillam. Around 80% of the company's aggregate requirements in the south east was imported by rail last year.
Although in need of restoration, the necessary rail infrastructure was already in place when the company began developing the Wembley facility, as it had previously been used as coal depot.
Rail freight operator English Welsh & Scottish Railways (EW&S) is managing rolling stock and train paths between Wembley and AI's quarries. 'We have 10 trains coming in every week, ' says plant manager Darren Griffiths. 'But the facility could receive double its intake of around 10,000t a week.'
INFOPLUS www. aggregate industries. co. uk
Time is tight
Screwfast Foundations has developed a piling system that saves time on railway upgrades by screwing tubular steel shafts in to the ground using conventional road/rail plant.
It takes about an hour and a half to remove a bucket and connect a Screwfast torque motor and meter in its place on a machine. No spoil arises from the pile installation.
Piles are screwed in and a steel grillage bolted directly to them, so a signal or stanchion can be bolted to the pile within two hours.
Screwfast is working in collaboration with a specialist signal manufacturer to erect a complete signal with piles, base grill and signal in a single visit of two hours.
INFOPLUS (01438) 833967
Learning the ropes remotely
Infrasoft will display the latest in computer software at Infrarail at the Wembley Exhibition Centre from 18 to 20 September. The software has been developed to allow driver training to take place inside the office. The solvSIGHTING and Sole RL software will be used to train experienced drivers on existing and proposed routes using pcs.
The systems can generate any route scenario in real time, giving trainees the opportunity to experience all variants.
SolvSIGHTING works hand-inhand with solvRL allowing the signal layout data to be migrated directly into the training application, so trainee drivers can learn from up to date, accurate simulations of routes previously unknown to them.
These routes are subject to constant change, especially around stations such as Paddington, due to new track developments and track improvement and maintenance projects leading to track changes and diversions.
INFOPLUS www. infrasoft-civil. com