The barrier between J3 and J4 was done around 2010. It's unusual in that it has lighting installed on top of it, whereas most CSB installations of the period shifted this to the verges. It is therefore possible the repairs are related to the cabling and ancillary features rather than the structural concrete itself.SJobson wrote: ↑Wed Aug 18, 2021 14:31 I commute along this stretch now; it was interesting to see the lane drop with no reduction in speed limit for the first few days, then a 40 limit but the lane drop removed for another few days, before the 40 combined with lane drop finally appeared in (I think) the second week. Nothing seemed to be going on during the first couple of weeks; it looked like the restrictions were a knee jerk reaction to a sudden finding of issues.
Yesterday morning I had the opportunity to look at the repairs being done. The central barrier had a few metres of nice fresh concrete in three or four places; there were markings on quite a number of crumbling edges where there were joins or joints in the barrier so I guess they're scheduled for repair in the same way. It looks like a fair bit of work, I guess done overnight.
What I can't remember is exactly when this section of the M5 had its concrete barriers installed. Googling hasn't brought up the answer because there are too many results about the Somerset section being replaced. It does seem quite early to require substantial repairs which knock out such a chunk of capacity for a decent length of time. Just glad my commute is the opposite direction to the main queues.
Also remember barriers installed in that period have been prone to serious failure - the M25 crossover was a good example. Far be it from me to suggest corners were cut to save money, but the method of installing the barriers changed around this period and the foundations were altered. This appears to have been a huge error given the M25 incident that has since been corrected.