This is very late. The autumn of 2018 has been a busy time. I am now in New Zealand for Christmas with my family and trying to catch up. Back in August I had a tour of Germany, Austria and Hungary. There is a string of bridges from that trip and here is one. More in the next few days.
As usual, there is a pdf file to download
Erfurt is in what used to be part of East Germany, the DDR. Amazing that it is nearly 30 years since the wall came down. I heard about the KraemerBruecke long after Sue had been there for a summer course. Indeed, I hadn’t even engaged with masonry at that stage. I have known of it for a few years but my grand tour in August was the first chance I had to visit.
This picture of the downstream side shows how modest the river is. We must assume that there are occasional floods justifying the ten spans. If you look at the map you will see a flood channel round the edge of town. The spire in this view belongs to the bridge chapel. The climb was worthwhile as it provided perhaps the best view along the bridge.
View from the new bridge.
From the guard tower at the end you get a lovely view of the street.There is obviously much more building than “highway”. It seems reasonable to suppose the buildings were originally supported on timber but the bridge has been widened on both sides.
Here we see the original bridge in the middle with a widening each side. The dressed voussoirs are a give-away that the central strip is original.
This display plan shows a number of interesting features. First, the bridge is obviously slightly skew over 8 spans from the left. There is then a kink and some much more questionable construction.
The piers vary considerably in width and it seems possible that the widest one near the middle might have originally been an abutment. On the other hand, the two river piers are very narrow for a bridge of this age, being less than half the span.
Something I would not have noticed otherwise is that the piers contain cellars, even under the roadway. They must either have been later excavations or the bridge was designed to carry building from the start. The income from ground rent would not be trivial so that is a reasonable assumption.
Both upstream and down, the buildings are carried on timber supports and the variation in these is also interesting.
Here you can see the original beam and inclined struts then a new leg supporting a further extension.
The prop and cantilever is an interesting structure. Three layers of beam of progressively greater length with shear keys to try to make them work together.
It doesn’t work as well as hoped judging from the tension crack by that central key.
This multi-tier gallery is an interesting variation.
The trussing format is quite interesting this is practically an arch with a beam on top.
This is definitely DDR work. A reinforced concrete imitation.
This is perhaps the most complex joint
To those looking for arch bridges, this is perhaps short change but in this bridge the arches are perhaps the least interesting feature. I have been in New Zealand for nearly four weeks and am finally finding the head space to catch up with these. There may be another before Christmas but just in case - Merry Christmas and Happy New Year to all our readers.