GFRP筋混凝土大偏心受压柱试验研究

Experiment Research of Large Eccentrically Loaded Concrete Column Reinforced with GFRP Bars

为了探寻GFRP筋混凝土大偏心受压柱的破坏机理和设计方法,完成了5根GFRP筋混凝土柱的大偏心受压试验,展现了GFRP筋混凝土大偏心受压柱从开始加载到破坏的全过程。重点分析了GFRP筋混凝土偏心受压柱在受拉区混凝土达到限值裂缝宽度0.5 mm时和受压区混凝土压碎时的状态,并对5根GFRP筋试件进行了有限元仿真分析。结果表明:GFRP筋混凝土大偏心受压柱的破坏模式是受拉区混凝土先达到限值裂缝宽度,然后受压区混凝土才被压碎;当受压区混凝土被压碎时受拉区裂缝宽度已经远远超过了限值0.5 mm,说明GFRP筋混凝土大偏心受压柱的设计极限状态是由裂缝宽度控制的。最后,得出了设计极限状态下受压区混凝土的压应变值,为GFRP筋混凝土大偏心受压柱的配筋计算提供了理论依据。

In order to explore the failure mechanism and the design method of reinforced concrete column subjected large eccentrically compression load,five columns prototypes reinforced with bars under large eccentrically compression were constructed and tested,showing the entire process from loading to failure.This paper focused on the analysis of the prototypes state in the tension area when the concrete reached the limit value of crack with width of 0.5 mm.In the compression zone when concrete crushes,finite element analysis was carried out for these prototypes.The experimental results indicate that the failure mode of all prototypes is that maximum crack width reaches limit,then following concrete crushes;when concrete crushes,the crack width in tension area far exceeds the limit value of 0.5 mm,which illustrates that design limit state of concrete column reinforced with bars under large eccentrically compression load is controlled by crack width.Finally,the concrete compressive strain was gotten in the compressed zone of the design limit state,which provides a theoretical basis for the reinforcement calculation of concrete column reinforced with bars under the large eccentrically compression load.