Fiber-reinforced polymer (FRP) wrapped concrete columns are vulnerable to accidental damage or vandalism, which may cause physical cuts or tearing of the jacket, thereby compromising the confined strength and ductility of the column. This paper aims at providing a simple tool to reassess the strength under a given level of damage. Finite element (FE) models were developed to examine a variety of cuts in the FRP jacket and develop a confinement model including the damage effects. After validation with 37 experimental tests from literature, the FE model was used in a comprehensive parametric analysis, examining different geometric and material variables, namely: cut orientation (longitudinal or circumferential); cut length and location, diameter-to-jacket thickness ratio, multiple cuts, concrete strength, and FRP elastic modulus. Results of the numerical models were analyzed using multiple nonlinear regression (MNR). New equations were developed to predict the reduction in axial strength and corresponding strain at ultimate. Reduction factors have been proposed, which are then easily implemented in commonly used confinement models in design guides such as ACI 440.2R.

纤维增强聚合物（FRP）包裹的混凝土柱很容易受到意外损坏或破坏，这可能会导致护套的物理割伤或撕裂，从而损害柱子的受限强度和延展性。本文旨在提供一种简单的工具，以在给定的损伤水平下重新评估强度。开发了有限元（FE）模型，以检查FRP护套的各种切口，并开发包括损伤效应的约束模型。经过文献中的37个实验测试的验证后，有限元模型用于全面的参数分析，检查了不同的几何和材料变量，即：切向（纵向或周向）；切割长度和位置，直径与外壳的厚度比，多次切割，混凝土强度和FRP弹性模量。使用多重非线性回归（MNR）分析了数值模型的结果。开发了新的方程式，以预测轴向强度和极限应变的降低。提出了降低因子，然后可以在设计指南（例如ACI 440.2R）中的常用限制模型中轻松实现。