Amtrak made a decision to replace an aging bascule bridge with a
vertical lift bridge for their crossing of the Thames River in New London,
Connecticut. The new lift bridge occupies the same alignment and
shares the same foundations as the bascule span. During construction
the deep foundation caisson supporting the bascule span settled and
tilted. Investigation into possible reasons revealed interesting historical
facts, both of the construction of the innovative open well caisson
foundations and of the state-of-the-art in tremie concrete placing
methods in use at the turn of the century. This paper describes both of
these topics.
Author: Alan D. Fisher, Cianbro Corporation
Publisher: DFI