Search Results: 'Wirth'

Choices for excavation–part 2
15 June, 2011
In this second and final part of our review of the extended capabilities of modern tunnel excavation methods, we examine the leading role of tunnel boring machines. Maurice Jones contacted some leading TBM manufacturers for their views and developments to expand the envelope of capabilities

Number four goes forth
15 June, 2011
Bhaskar Thapa of Jacobs Associates and Axel Nitschke of Gall Zeidler Consultants report on progress at the Caldecott fourth bore project

Flexible and forceful
09 June, 2011
Another tunnel excavation method that has been utilising design improvements to successfully push the limits of operational efficiency is the use of roadheaders. Originally developed as relatively soft-ground machines, particularly for sedimentary deposit mining, they are being used increasingly in harder rock excavation. They are also challenging drill-and-blast for places in projects requiring flexibility and suitability for urban tunnelling, especially with regard to vibration and accuracy. Maurice Jones reports

Choices for excavation
09 June, 2011

Strabag buys shield machines for Koralm
20 May, 2011

Powering up at Linthal-Limmern
14 March, 2011
The topography of alpine and similar mountainous areas presents both many challenges and opportunities for tunnelling engineers. Whereas the current focus has naturally been on rail base-tunnels, the business of constructing and expanding hydropower facilities continues apace. Maurice Jones summarises recent developments at the Linthal-Limmern hydropower complex

Lining with security and efficiency
14 February, 2011
Second only to the ‘excitement’ of watching paint dry in frustration stakes, at least in tunnelling, is waiting for concrete to cure. Maurice Jones examines how formwork and concrete mixtures are increasing the efficiency of cast in situ concrete tunnel lining

Progress on Brisbane’s trio of road projects
18 January, 2011
A year and a half away from its scheduled delivery, tunnelling for Brisbane’s Airport Link and related projects is on track—with a little help from revising the alignment, Nicole Robinson finds