Time-dependent behaviour of curved composite beams with partial interaction

The research presented in this thesis is concerned with the time-dependent creep and shrinkage behaviour of steel-concrete composite curved beams with partial interaction. The research program comprises both theoretical studies and experimental investigations.Firstly, an efficient numerical method is developed for the creep and shrinkage analysis of steel-concrete composite beams curved in-plan. The flexibility of the shear connection in the radial and tangential directions at the steel-concrete interface is taken into account in the developed method. The creep and shrinkage effects of the concrete deck are considered by using the analytic Age-adjusted Effective Modulus Method. The accuracy and efficiency of the proposed approach are validated by comparing its results with available experimental results reported in the literature and with those based on an ABAQUS shell finite element model. Parametric studies are also undertaken, which demonstrate that the initial curvature and partial interaction of the beam have significant influences on the time-dependent behaviour of composite beams curved in-plan.The geometrically nonlinear time-dependent creep and shrinkage behaviour of horizontally-curved steel-concrete composite beams with partial interaction is also investigated. In order to include the effects of geometric nonlinearity, a step-by-step iterative procedure is used for the creep and shrinkage analysis. The examples presented illustrate that the geometric nonlinearity should be considered for an accurate time-dependent analysis of composite beams curved in-plan.The experimental program, which involves testing the time-dependent behaviour of a simply-supported steel-concrete composite beam that is curved in-plan, is reported. The experimental results provide benchmark data to test the validity of the theoretical model developed for the time-dependent creep and shrinkage analysis of curved composite beams, and for subsequent studies by other researchers.Finally, a numerical formulation for the nonlinear time-dependent creep and shrinkage analysis of spatially-curved steel-concrete composite beams with partial interaction is also developed. The verifications indicate that the proposed formulation for the time-dependent analysis of composite beams curved in-space is accurate. The effects of partial interaction, initial curvature and the curvature components are also illustrated with chosen examples to elucidate this complex structural behaviour