pumpkinstrokemarrow

Ask Google about the Star, and he seems to think that it is primarily, although not exclusively, a Jewish symbol. A motif worked into books, pavements and architectural decoration generally. So the anxious lady might have a point; not the thing you would expect to see in a Victorian chair in a Christian church.

Ask Google about the synagogue, and that certainly exists too, just around the corner from the church, in Synagogue Place. We will have to pay a visit next time we are in the regional capital. Perhaps the chair was the subject of an inter-faith solidarity exchange between the two institutions? Again, something to ask about next time.

The puzzle nearer home is the East Road railway (over road) bridge which was replaced over the Easter weekend, having first been noticed on April 8th. According to our free newspaper, the deck for the new bridge is a piece of steelwork weighing around 150 tons. Each end of the deck sits on three bearers, the three bearers sit on a new concrete plinth and the plinth sits on top of what is left of the brick abutment. The bearers are concrete cubes, with a side length of perhaps one foot and there is a layer of something else, much darker than the concrete and maybe two inches thick, between the bearer and the steelwork. There is probably another layer of something between the bearer and the plinth, but one can't see that from the road.

My puzzle is that 150 tons is a lot of tons. You can't just dump that sort of weight on fresh concrete and the operation of taking one deck out and putting the new deck in must have been completed in under a week. Sadly we were away and were unable to keep a close eye on the operation.

So how was it done? Was the new concrete plinth cast in-situ on top of the truncated brickwork - old brickwork which had been stabilized by the work of the preceding fortnight or so? You would not have to wait very long before it could take the weight of the bearers, but how long before it would take the weight of the deck on top of the bearers? The bearers themselves could have been made well in advance and so would be well up to spreading the point loading of the steel deck out into a spread loading that the new concrete plinth could cope with. Perhaps the key is the stuff between the deck and the bearer and the bearer and the plinth. Being thin it does not have to be terribly strong - a bit of compressive strength would be enough - but it does have to dry quick. Have the deck on jacks, bed it down on the quick drying goo, wait a couple of days and then take the jacks out?

I do recall works in the road under the bridge, consistent with large jacks being installed there.