Flexural rigidity of segmental joints in cantilever casting concrete bridges

Special attention in design and construction should be paid to joints between segments in cantilever casting concrete bridges. These joints introduce discontinuity in the bridge; furthermore they weaken the connection rigidity and strength of corresponding section, which may lead to excessive downwarping of bridge. Experiments were carried out to assess the flexural rigidity of segmental joints section. The parameters studied included monolithic non-joints, joints roughened, joints roughened with bending-key. It was found that the flexural rigidity of jointed section is largely lower than that of non-jointed section; however, the bending-key can effectively enhance the flexural strength and especially flexural rigidity of the jointed section. Measures are proposed for bending-key design, which may provide a rational basis for the design of cantilever casting concrete bridges.