Few reports have described practice-based models assessing ultimate strengths of existing reinforced concrete (RC) members subjected to frost damage. This paper presents a kinematic model for shear assessment of damaged RC short columns based on the upper bound theorem. Without regressive functions, the developed model predicts the shear strength contribution of damaged concrete when the displacement field is divided into undamaged and damaged zones based on damage depths obtained from core sampling. The model accuracy is verified by comparison of its predictions with those of earlier test results of 14 RC columns presenting shear failure after freeze–thaw exposure. The analytical predictions show good agreement with experimentally obtained results within error of 20%. Shear strength predictions for different damage depths are presented for an existing RC bridge pier with severe frost damage. Rational shear assessment was achieved because the kinematic analysis directly correlates the damage depth with shear strength reduction.

很少有报告描述基于实践的模型来评估遭受霜冻破坏的现有钢筋混凝土（RC）构件的极限强度。本文提出了基于上限定理的受损钢筋混凝土短柱剪力评估的运动学模型。在没有回归函数的情况下，所开发的模型会根据岩心采样获得的破坏深度，将位移场分为未破坏区域和受损区域时，预测受损混凝土的抗剪强度贡献。通过将模型的预测结果与14根RC柱的冻融暴露后出现剪切破坏的早期测试结果进行比较，验证了模型的准确性。分析预测显示与实验获得的结果吻合良好，误差在20％以内。对于存在严重霜冻破坏的现有RC桥墩，提出了针对不同破坏深度的抗剪强度预测。运动学分析将损伤深度与剪切强度降低直接相关，从而实现了合理的剪切评估。