Latest from Tunnels and Tunnelling
Located mostly in Brazilian rainforest, the Tamoios highway and tunnel project is of critical importance to the Brazilian economy. It was the subject of the BTSYM talk in September given by project director Pedro Soares dos Anjos. Report by Divik Bandopadhyaya of London Bridge AssociatesRead more
Two TBMs are being retrofitted in Brisbane, Australia in preparation for the city’s Cross River Rail project which has a total length of 10.2km and includes 5.9km of twin tunnels.
NHI advancing on TBM coal-mining front
China’s Northern Heavy Industries (NHI) – which has a controlling stake in US-based The Robbins Co – has claimed it is creating a new era in China with the use of tunnel boring machines (TBMs) in coal mining on a greater scale than ever before.
Traylor-Shea to design and build RiverRenew tunnel system
US-based AlexRenew – the public utility for water renewal in Alexandria, Virginia – has awarded a US$454.4m contract to Traylor-Shea Joint Venture to design and construct the RiverRenew Tunnel System Project.
Hudson tunnel still suffering from Hurricane Sandy
With a litany of problems, many stemming from the Hurricane Sandy flooding of October 2012, a soon to be published study by Amtrak will urge urgent repairs are needed to the Hudson Tunnel in the next few years if ‘potentially catastrophic failures’ are to be avoided.
UK breaks record for longest hydraulically-inserted pipeline
UK energy company National Grid has completed what has been hailed as the world’s longest hydraulically-inserted pipeline, now officially recognised by Guinness World Records.
Choosing the right steel fibre for FRC precast tunnel segments can have a significant impact on performance, productivity and cost, explains Benoit de Rivaz, Global Technical Manager BP Underground, Bekaert
Melbourne’s big dig
Four TBMs are at work on the Melbourne Metro – a new line comprising two 9km-long tunnels that will run beneath the central business district and where monitoring for ground movement was critical. Julian Champkin reports on the progress
Canadian distance record
Microtunnelling can save costs, surface disruption and inconvenience to the public, while the distances that can be covered are increasing. Julian Champkin looks at a 5km project in Canada and asks whether the technique can stretch even further
Rock Mass Classification Systems
Rock mass’ refers to an accumulation of rock material separated by rock discontinuities, mostly by joints, bedding planes, dyke intrusions and faults. When a rock mass is intersected by a sufficiently large number of weak planes such that rock-mass behaviour is not controlled by failure on individual planes, the mass’s behaviour will tend towards the continuum type of behaviour again. However, the numerous planes in the mass (usually weaker than the rock material), will significantly influence rock behaviour. In such cases, rock mass classification is commonly used to evaluate the rock mass behaviour.
Structural design and classification of FRC for tunnel linings
Axel G Nitschke, Tunnel Practice Leader at WSP USA, looks at the use of fibre-reinforced concrete and suggests a labelling and classification system designed to provide an effective and easy way to specify FRC for tunnel linings