局部受压混凝土圆柱及其FRP增强的弹塑性分析

Elastoplastic Analysis of Local Compression of Concrete Cylinder and Its FRP Reinforcement

局部受压混凝土圆柱核心区受压膨胀,外围混凝土对其产生的径向约束力能提高其强度和变形能力。本文引入混凝土弹性模量连续变化的计算模型,应用弹性力学方法进行外围混凝土弹塑性分析。基于混凝土三轴抗压强度Richart公式计入外围混凝土径向约束力对核心区受压混凝土的影响,提出了局部受压混凝土圆柱极限承载力的计算方法。在上述理论研究基础上,进一步对FRP增强的局部受压混凝土圆柱的极限承载力进行求解,分析了局部受压混凝土及其FRP增强圆柱的极限承载力,理论计算与有限元吻合较好。

The core area of a concrete cylinder will be expanded when compressed by the local load.In such a case,a radial binding force from the outer layer of the concrete can significantly enhance the strength and ductility of the cylinder.In the present analysis,the outer part of the concrete cylinder was analyzed by using the simplified calculation model,in which the elastic modulus continuously varies.Considering the effect of radial stress of the peripheral concrete,the Richart formula was used to analyze the mechanical behavior of the core area of the concrete cylinder.The analytical method for the ultimate bearing capacity of the concrete cylinder under local compression load was developed.In addition,by using the present method,the ultimate bearing capacity of concrete cylinder reinforced by FRP under local compression was also calculated.Finally,the parameter analysis of locally compressed concrete cylinder with FRP reinforcement was also performed.The results are in good agreement with the finite element solutions.