Finite Element Modelling of Concentrated Anchorage Load in Early Age Concrete

Abstract

Analyses of end-block and beam-end specimens have been undertaken based on the finite element models. The purpose of the analyses is to investigate the effects of concrete early age properties on the response behaviour of the anchorage zone. Time dependent strains and stresses in the anchorage zone are evaluated. The mechanical concentrated load represents the anchorage in post-tensioning of slab or beam during construction where the load is transferred typically at 1 and 4-days ages. The analyses incorporate thermal, creep and shrinkage effects. The double power law (DPL) is adopted to represent the creep effects. The ACI 209 and the CEB-FIP shrinkage models in FE TNO DIANA were also adopted to account for shrinkage. The models are validated based on experiments. Results indicate that early ages concrete effects need to be considered for design of sensitive elements in particular such as anchorage zones of post-tensioned elements.