measurements of creep and shrinkage in the concrete of the medway bridge (m2), rochester, kent, which is of the cantilever type, have been made since the time of construction in 1963. the movement was found to be generally linear with the logarithm of time, with an imposed cyclic seasonal movement; the creep factor to din 4227 for the top slab, which was prestressed from the day after casting over a period of two months, is estimated to be about 2.2 at 10,000 days, while that for the lower slab, which was loaded much later by dead load stresses, is about 1.5. the corresponding estimated shrinkage is 120 x 1/000000 in the bridge and about 400 x 1/000000 in companion specimens stored in the bridge, thus showing a large size effect. work on german and austrian bridges is reported and it is noted that the order of magnitude of the ultimate creep factors is likely to be similar to that obtained for the medway bridge. calculations using different sets of european recommendations for the prediction of movement showed that the german standard din 4227 gave results near to those obtained from the measurements and yet was simple to use and allowed for the main factors affecting movement (a).

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