by sebastianbear » Tue May 31, 2016 8:58 pm
Soil conditions may be difficult in Tooting than in Balham, but a number of people have suggested using different technologies that have been used successfully in other challenging locations. The most recent suggestion was a comment on a profile piece on Michele Dix in The Engineer 15th April -
"Geoff NH wrote on 6th May 2016
The boring through different sub soils can easily be countered by using the Dutch method of “Freezing the surrounding ground”, no matter whether it has water in or not. The biggest under ground use was on the “Boston Big Dig” and went very easily. Also with directional drilling as used in the Oil Industry. Any freezing support equipment can be place away from areas where it could interfere.
Just think outside the box about using this technique for under ground boring through different soil structures, will save having to divert routes around a problematic soil. So by freezing the soils allows the tunnel boring; till the surrounding soils can be supported by the tunnel support structures and sealants, then allow the soils to thaw out as the systems goes forward."
I have no idea whether this would work, but given the economic and social benefits of choosing Tooting, I hope Crossrail are looking at a variety of techniques - and will be prepared to be a little more open about what they are considering and the assumptions behind their models - than they have been so far.
Soil conditions may be difficult in Tooting than in Balham, but a number of people have suggested using different technologies that have been used successfully in other challenging locations. The most recent suggestion was a comment on a profile piece on Michele Dix in The Engineer 15th April -
"Geoff NH wrote on 6th May 2016
The boring through different sub soils can easily be countered by using the Dutch method of “Freezing the surrounding ground”, no matter whether it has water in or not. The biggest under ground use was on the “Boston Big Dig” and went very easily. Also with directional drilling as used in the Oil Industry. Any freezing support equipment can be place away from areas where it could interfere.
Just think outside the box about using this technique for under ground boring through different soil structures, will save having to divert routes around a problematic soil. So by freezing the soils allows the tunnel boring; till the surrounding soils can be supported by the tunnel support structures and sealants, then allow the soils to thaw out as the systems goes forward."
I have no idea whether this would work, but given the economic and social benefits of choosing Tooting, I hope Crossrail are looking at a variety of techniques - and will be prepared to be a little more open about what they are considering and the assumptions behind their models - than they have been so far.