In this paper, laboratory tests to failure of ten large deep beams with I-shaped cross-sections are presented. All beams had the same geometry with a shear span-to-depth ratio of 1.25 but differed in the amount of the vertical and horizontal web reinforcement. The presented results from the measurements consist of load-deformation curves, crack widths and crack patterns and strain distribution near the supports. The ultimate loads for these beams have been calculated with two strut-and-tie models and one truss model. The first strut-and-tie model calculates the tensile contribution of both reinforcement and concrete and takes into account their influence on the principal tensile stress. The second strut-and-tie model is a modification of the first one where the stress distribution along the strut is redefined. The third method is the truss model that is incorporated in a Design Code. The truss model gave the best result for the beams with a higher reinforcement ratio that exhibited in a shear compressive failure. The diagonal tensile failure that occurred in the beams with a small amount of web reinforcement was best captured with the modified strut-and-tie model.

In this paper, analyses based on laboratory tests of ten large deep beams with I-shaped cross-sections loaded to failure are presented. All beams had the same geometry with a shear span-to-depth ratio of 1.25, but differed in the amount of the vertical and horizontal web reinforcement. All beam tests resulted in shear failure, either diagonal tensile failure or shear compressive failure, depending on the amount of reinforcement. The diagonal tensile failure is generally considered to be the most difficult failure to treat numerically. In this study different material models incorporated in commercial numerical analysis tools are studied. Material models based on fracture mechanics with either rotated or fixed crack directions as well as a plasticity-based model are used in the analyses. The analyses show that the plasticity-based model in Abaqus gives good agreement with the experiments regarding crack pattern, load-displacement response and estimated crack widths. The models based on fracture mechanics in Atena and Response tend to give too stiff behaviour in the load-displacement response, but generally give a good estimation of the load capacity. The analyses performed with Atena gave good estimations of the crack pattern, and the models with a fixed crack direction also gave good estimates of the crack width.

Segmentally constructed concrete cantilever bridges often exhibit larger deflections than those predicted by the design calculations The slender and long spans in combination with the fact that permanent loads are only partially compensated for by prestressing are reasons for the large deflections that increase during the life time of the bridge, although at a decreasing rate The rate of drying shrinkage may be one reason for the accelerating displacement of cast-in-place bridges The construction of continuous spans instead of introducing joints has both comfort and durability advantages The continuous span is however more complicated to design, and secondary restraint moments due to creep, shrinkage and thermal effects develop at the connection The results of analyses of the stepwise cast-in-place construction of a balanced cantilever bridge with time-dependent material properties show both higher deflect ion than those originally assumed in the design calculations and high stresses in the webs due to stressing of the tendons in the bottom flange The analyses show significant effects of creep during cantilevering and of a non-uniform drying shrinkage rate on the continuous bridge