Cao Yu-Gui, Jiang Cheng, Wu Yu-Fei
School of Civil Engineering and Mechanics, Huazhong University of Science & Technology, Wuhan 430074, China.
Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong SAR, China.
Polymers (Basel). 2016 May 11;8(5):186. doi: 10.3390/polym8050186.
The stress-strain behavior of concrete can be improved by providing a lateral passive confining pressure, such as fiber-reinforced polymer (FRP) wrapping. Many axial stress-strain models have been proposed for FRP-confined concrete columns. However, few models can predict the stress-strain behavior of confined concrete columns with more than two specified cross-sections. A stress-strain model of FRP-confined concrete columns with cross-sectional unification was developed in this paper based on a database from the existing literature that includes circular, square, rectangular and elliptical concrete columns that are highly confined by FRP jackets. Using the database, the existing theoretical models were evaluated. In addition, the ultimate stress and strain models with cross-sectional unification were proposed using two parameters: the cross-sectional aspect ratio and corner radius ratio. The elliptical cross-section can be considered as a rectangular one with a special corner radius for the model calculations. A simple and accurate model of the equivalent corner radius ratio for elliptical columns was proposed. Compared to the other existing models and experimental data, the proposed models show good performance.
通过提供横向被动约束压力，如纤维增强聚合物（FRP）包裹，可以改善混凝土的应力-应变性能。许多轴向应力-应变模型已被提出用于FRP约束混凝土柱。然而，很少有模型能够预测超过两个特定横截面的约束混凝土柱的应力-应变行为。本文基于现有文献中的数据库，开发了一种具有横截面统一的FRP约束混凝土柱的应力-应变模型，该数据库包括由FRP护套高度约束的圆形、方形、矩形和椭圆形混凝土柱。利用该数据库，对现有的理论模型进行了评估。此外，使用两个参数：横截面长宽比和角半径比，提出了具有横截面统一的极限应力和应变模型。在模型计算中，椭圆形横截面可被视为具有特殊角半径的矩形横截面。提出了一种简单而准确的椭圆形柱等效角半径比模型。与其他现有模型和实验数据相比，所提出的模型表现良好。
