基于安全储备指标的预应力FRP加固设计方法

Prestressed FRP reinforcement design method based on safety reserve index

预应力FRP加固技术在建筑加固中得到了广泛应用,但由于加固构件在破坏前变形能力不足,而其承载能力在钢筋屈服后仍具有较高的增长,所以仅以变形延性系数评价此类加固构件的安全储备显然并不全面,因此,寻求合理的评价指标就显得尤为重要。为解决这一问题,提出了用安全储备指标来评价这类构件安全性的理念,并进行了定性分析与定量预测,基于双折线假设建立了安全储备指标的预测模型。研究表明:等效安全储备指标Keq与传统的延性系数相比可以更为全面的分析加固构件的安全储备情况,通过对计算值和模拟值进行对比,发现该模型具有较好的准确度,因此加固工程中,可以基于目标安全储备指标完成FRP加固面积的计算。

Prestressed FRP reinforcement technology has been widely used in building reinforcement.However,due to their insufficient deformation ability of the reinforcement member before destruction,their bearing capacity still has a relatively high growth after the steel bars yield;So obviously,it is not comprehensive to evaluate the safety reserve of such reinforced components only by deformation ductility coefficient.Therefore,it is particularly important to seek a reasonable safety reserve index to evaluate such reinforced members.To solve the problem,this article puts forward the concept of using the safety reserve index to evaluate the safety of such components,and analyzes from qualitative analysis and quantitative prediction,and the prediction model of safety reserve index is established.The research shows that the equivalent safety reserve index can be used to analyze the safety reserve of reinforced members more comprehensively compared with the traditional ductility coefficient.The model has better accuracy by comparing the calculated value with the simulated value.Therefore,in the reinforcement project,the calculation of the FRP reinforcement area based on the target safety reserve index can be completed.