Despite the works extensive works done in the past few years, Concrete cancer has returned to the Uxbridge station roof with a small area fenced off by platform 4. (could be 1) and one or two other areas showing small signs of return.
Dose anyone know if this is just a small area with problems, or if the whole structure has real problems, possibly fatal.
It looks like it's isolated to the area above the buffers end of platform 4 which I believe has been cordoned off for at least a year now. From the photo I took today, it looks like its water ingress caused by poor run off drainage which has been a persistent issue in the past.
My knowledge of civil engineering is about nil, so take the following with a pinch of salt, but that does not look like water damage. Concrete is used for sea walls and has been used for roads and motorways so is not particularly susceptible to water damage from surface contact, provided it has been poured correctly and not suffered mechanical damage.
The section illustrated appears to have delaminated which would imply a faulty mixture that has cracked and allowed water ingress and possibly freezing which could break off chunks.
I'm not a civil engineer either, but I think water ingress is a probable factor here. Also the reinforcing bars are very close to the original surface which is bad practice and can accelerate corrosion and spalling. On a less serious structure one can recall the cast reinforced concrete fencing at Rayners Lane and Sudbury Town that had widespread failing like this and was completely renewed some years ago as part of retaining the heritage appearance.
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