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This paper develops a numerical formulation for the nonlinear time-dependent analysis of steel-concrete composite members that are curved arbitrarily in space, which includes the effects of concrete shrinkage, creep, and geometric nonlinearity. This formulation is applicable to the analysis of composite arches and composite beams curved in plan, representing the limiting cases of members that are vertically and horizontally curved. The flexibility of the shear connection at the interface surface between the steel girder and the concrete deck is taken into consideration in the formulation. For an accurate serviceability limit state analysis of composite curved members, it is essential to include the shrinkage and creep response of the concrete component in the analysis. To also include the effects of geometric nonlinearity, a step-by-step incremental iterative solution procedure is adopted. Comparisons of the numerical solutions with those based on much less efficient and tractable viscoelastic ABAQUS shell element models, and with available experimental results, verify the accuracy of the computational formulation that is developed. Examples are chosen to illustrate the effects of partial interaction and initial curvature on the time-dependent behavior of spatially curved composite beams. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive experimental study of the time-dependent creep and shrinkage behavior of a simply supported steel-concrete composite beam that is curved in its plan; it is a companion to the first paper that presented a numerical model for spatially curved members for which a beam curved in plan is a limiting case. The full-scale beam was tested under sustained uniformly distributed loading for approximately 250 days; its time-dependent deformations and strains were monitored throughout the period of loading. Separate companion concrete specimens were tested under the same ambient conditions as the test beam to determine the creep and shrinkage characteristics of the concrete component of the beam. The test observations show that the creep and shrinkage behavior of the concrete component has a significant effect on the long-term response of curved composite beams. The experiment also provides benchmark data to test the validity of theoretical models and shows that the developed numerical technique is able to predict the deflections of the test beam acurately; hence, it is able to provide a reliable computational model from which to formulate design guidance. [ABSTRACT FROM AUTHOR]