State-of-the-Art of Integral Abutment Bridges: Design and Practice

The superstructure for integral abutment bridges is cast integrally with abutments that are supported by a single row of piles. Thermal expansion or contraction and concrete creep and shrinkage induce bending stresses in the piles. Very limited design and construction guidelines are available and no unified design procedures exist nationwide; hence, there is a lack of enthusiasm to adopt integral abutment bridges for long spans. Current design and construction practices of integral abutment bridges have been reviewed. Important design parameters are identified with an emphasis on temperature, creep, and shrinkage effects of concrete bridge decks, varying soil strata, and the pile-soil interaction. A parametric study is described regarding the effects of a predrilled hole, the type of fill in the predrilled hole, elevation of the water table, soil type, and pile orientation. The results from the parametric study should aid in the selection and design of piles for integral abutment bridges.