I find it interesting to think that workers are slowly digging out the tunnel under Cromwell Road, according to a recent HS2 TH-cam video where they say the tunnel is half complete. It would seem they are doing this from the western side, as you can see that on the eastern side the soil is still in place. A clue is at 3:47 or so in the video: you can see two large black pipes either side of the roof opening connected to green air blowers - giant fans - that I believe are providing an air supply to workers and machinery digging away under Cromwell Road. It looks like they could reinstate the original line of the road some time soon. However, that work will doubtless be delayed by the need to get the utilities companies to restore their pipes and ducts into the new road section - so that could be a year or two away!
any reason as to why u have not put more form shuttering up,could space them out at a certain distance ,then come back and fill them ,as i see it you fill this part ,wait for it to dry ,then strip it down and start another form,hence have forms up already ,its hanging the job out doing this way,the other way at least u have the continuity of it,and not time wasting
It seems an expensive solution given there was a railway in a cutting there for over 100 years previously. I guess the residents are used to their greenway so it's about keeping them happy? Presumably there's a reason they are digging underneath a concrete slab rather than digging a trench and then pouring concrete, risk of collapse maybe?
@garthcox4307 it was, I recall, a single track coal line, which I walked up in 1979 after closure. Wholly inadequate for a highcapacity twintrack segment of the UK's new spine railway for the next 120 years.
Not digging under a concrete slab. Firstly they cut slot trenches in the ground and filled them with concrete to create the tunnel walls. Crossbeams were then poured from wall to wall to brace the structure during excavation. Most of the soil has been lifted out vertically. The floor slab was next, followed by the internal dividing wall. The concrete roof will be next followed by the backfilling, and then the pretty part, the landscaping.
Thank you for a late November update on this section - saves me going down there until Spring. Appreciate your dedication.
I find it interesting to think that workers are slowly digging out the tunnel under Cromwell Road, according to a recent HS2 TH-cam video where they say the tunnel is half complete. It would seem they are doing this from the western side, as you can see that on the eastern side the soil is still in place. A clue is at 3:47 or so in the video: you can see two large black pipes either side of the roof opening connected to green air blowers - giant fans - that I believe are providing an air supply to workers and machinery digging away under Cromwell Road. It looks like they could reinstate the original line of the road some time soon. However, that work will doubtless be delayed by the need to get the utilities companies to restore their pipes and ducts into the new road section - so that could be a year or two away!
any reason as to why u have not put more form shuttering up,could space them out at a certain distance ,then come back and fill them ,as i see it you fill this part ,wait for it to dry ,then strip it down and start another form,hence have forms up already ,its hanging the job out doing this way,the other way at least u have the continuity of it,and not time wasting
It seems an expensive solution given there was a railway in a cutting there for over 100 years previously. I guess the residents are used to their greenway so it's about keeping them happy? Presumably there's a reason they are digging underneath a concrete slab rather than digging a trench and then pouring concrete, risk of collapse maybe?
HS2 isn't exactly going to be an interesting journey if it's mainly in tunnels.
@garthcox4307 it was, I recall, a single track coal line, which I walked up in 1979 after closure. Wholly inadequate for a highcapacity twintrack segment of the UK's new spine railway for the next 120 years.
Seems like the old nineteenth century “cut and cover”.
Not digging under a concrete slab. Firstly they cut slot trenches in the ground and filled them with concrete to create the tunnel walls. Crossbeams were then poured from wall to wall to brace the structure during excavation. Most of the soil has been lifted out vertically. The floor slab was next, followed by the internal dividing wall. The concrete roof will be next followed by the backfilling, and then the pretty part, the landscaping.