Simulation of self-centering, segmentally precast concrete columns for a probabilistic, performance-based assessment

摘要

For reinforced concrete bridges, a key measure of post-earthquake functionality is residual displacement. To mitigate the problem of residual displacements, a system that uses vertical, unbonded postten-sioning (UBPT) to facilitate self-centering is under investigation. Engineered Cementitious Composites (ECC) are also proposed to provide hysteretic energy dissipation and damage tolerance to the system. This paper will present simulations performed on large-scale experiments on segmentally precast UBPT bridge columns using ECC in localized regions. The objective is to evaluate modeling techniques that can be used to assess the system within a performance-based earthquake engineering assessment methodology. The models are 2D plane stress analyses incorporating nonlinear constitutive models for the steel, concrete and ECC. The cyclic load-displacement response for the specimens was captured well in the simulations. The level of residual displacements were not captured as well. The overall validity of the proposed simulation models will be discussed.