Date of Award


Publication Type

Doctoral Thesis

Degree Name



Civil and Environmental Engineering


Engineering, Civil.


Kennedy, J.




The use of horizontally curved bridges has increased considerably in recent years for highway bridges and interchanges in large urban areas. Due to the increasing demands for reduced dead weight and for efficient cross-section in distributing the wheel loads, waffle slab construction is introduced. In the past, bridge design engineers have shied away from using waffle slab construction since they considered it incompatible to the predominately one-way supporting system of a bridge. However, a horizontally-curved bridge can be subjected to large twisting moments. Therefore, the orthogonal rib system in a waffle slab construction provides an efficient resistance for such twisting moments. In this research, theoretical and experimental studies were carried out to determine the various rigidities of curved concrete waffle slab bridges and to investigate their behaviour under working and ultimate loads. In the analyses, the finite difference technique, the finite element method and the yield-line theory were used. Simplified yield-line expressions were developed to predict the collapse load of curved reinforced and prestressed concrete waffle slab bridges. These expressions were based on both parametric study as well as on laboratory test results on curved waffle slab bridges. Also, the structural responses of curved prestressed concrete waffle slab and girder-slab bridges are examined for the effect of prestressing, working load and ultimate load. An analysis for the effect of the high radial forces, generated by the horizontal curvature of the prestressing tendons is proposed. Furthermore, a parametric study was conducted to examine the influence of bridge horizontal radius to width ratio, bridge aspect ratio, loading position and the presence of the transverse ribs on the elastic and post-elastic behaviour of such bridges. The experimental program is divided into two groups: the first group deals with the rigidities of curved waffle slab structures and consists of nine tests on horizontally curved concrete waffle slab. The second group deals with the behaviour of curved concrete waffle slab bridges. It consists of testing three curved concrete slab bridges: the first model was a curved reinforced concrete waffle slab bridge; the second model was a curved prestressed concrete waffle slab bridge, while the third model was a curved prestressed concrete girder-slab bridge to study the effect of the transverse ribs on the behaviour of curved bridges. Good agreement between the theoretical and experimental results is found. Both the analytical and experimental results demonstrated that both the elastic and post-elastic response of curved waffle slab bridges are superior to those of girder-slab bridges. Results from the parametric study revealed that the bridge horizontal radius to width ratio, aspect ratio, loading position and the presence of the transverse ribs significantly influence the elastic behaviour as well as the ultimate load capacity of such structures.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1993 .A578. Source: Dissertation Abstracts International, Volume: 55-05, Section: B, page: 1945. Adviser: J. B. Kennedy. Thesis (Ph.D.)--University of Windsor (Canada), 1993.