9. Integral Bridge

In the integral bridge concept, the deck and the abutment structure are not separate structural components but constitute a single monolithic structure. The integral bridge under consideration has a post-tensioned concrete deck which is monolithically connected to a transverse concrete beam. Both the deck and transverse beam are cast in situ. The transverse beam is rigidly fixed to concrete-filled tubular steel piles. The case is modelled as a two-dimensional problem. The D-region consists of the transverse beam and parts of the bridge deck and tubular piles. The interaction between the piles and transverse beam is discussed, and a stringer-panel scheme is chosen. Although the model is statically indeterminate, the member forces are calculated on the basis of considerations of equilibrium alone, which is enabled by some assumptions made as to the distribution of shear stresses in the transverse beam. A strut-and-tie model is developed from the obtained SPM solution. Finally, the translation of the two-dimensional SPM results into spatial forces and reinforcement in the transverse beam is discussed.