ANALYTICAL MODELLING OF THE SEISMIC BEHAVIOUR OF PRECAST CONCRETE FRAMES DESIGNED WITH DUCTILE CONNECTIONS

Pure precast beam-column systems incorporate unbonded reinforced at the critical sections, causing strain incompatibility between steel and concrete. As a result, classical section analysis method, well know for characterising monolithic concrete members, cannot be directly applicable to these systems. This paper provides a section analysis method suitable for precast members, incorporating, through an analogy with equivalent cast-in-place solution named “monolithic beam analogy”, an additional condition on the member global displacement. The proposed method was first validated with the experimental data from tests on beam-column Hybrid subassemblages. Using appropriate hysteresis rules and the response envelopes defined by the section analysis method, a prediction of the behaviour of the PRESSS test building was carried out. Satisfactory agreements obtained between the analytical and experimental results confirm the validity of the suggested methodology. Derivation of the method and experimental validation are herein presented.     

STRUT-AND-TIE COMPUTER MODELLING OF REINFORCED CONCRETE BRIDGE JOINT SYSTEMS

Nonlinear inelastic force-displacement response envelopes of large scale bridge tee-joints and multi-column bridge bents were established using strut-and-tie models (STMs) representing the entire structural system. The computer based STMs employed in the current study were formulated based on the force transfer mechanisms in the joint panel region reported in the literature, in conjunction with the formulation procedure for beam and column members that has been previously reported by the authors. Analysis was performed using the nonlinear analytical program Drain-2DX. Obtained analytical results, including response envelopes and sequences of structural failure, were found to correlate satisfactorily with those obtained from the experimental data.