预应力FRP片材约束混凝土方柱应力-应变模型

Modeling on Stress-Strain Relationship of Square RC Columns Confined with Lateral Pre-Tensioned FRP Sheets

采用预应力FRP片材加固混凝土柱是一种新型加固方法,能够避免FRP片材的应变滞后,加强FRP片材与混凝土之间的协同工作,提高FRP片材的加固效率,改善被加固柱的受力性能。基于已有的FRP片材约束混凝土方柱的应力应变模型,考虑预应力FRP片材对混凝土柱的主动约束作用,提出了一种预应力FRP片材约束混凝土方柱的应力-应变关系模型。模型的计算分析结果表明,预应力FRP片材的主动约束可以显著提高混凝土方柱的延性和抗压承载力,和既有结果比较一致。

The concrete column strengthening technology with prestressed FRP sheets is new strengthening technology.By using this technology,strain hysteresis of FRP sheets can be avoided;the cooperative working performance of concrete and FRP sheets,the availability of FRP sheets and the mechanical property of concrete columns can be improved significantly.Based on the existing stress-strain models of FRP confined concrete square columns,a new stress-strain model of concrete square columns confined with pre-tensioned FRP sheets was proposed.In this model,the active confined stress supplied by pre-stressed FRP sheets was emphasized.Analysis results by the recommended model can match the other test results,which shows that the ductility and normal section compressive capacity of concrete square columns can be significantly increased with the effect of prestressed FRP sheets.