有初应力的FRP约束混凝土圆柱应力—应变分析型模型

Analysis-Oriented Stress-Strain Model for FRP Confined Circular Concrete Column with Initial Stress

为准确模拟有初应力的纤维增强复合材料(FRP)约束混凝土的单轴受压性能,基于采集的103个试验数据,引入初应力水平影响因子,提出考虑初应力的FRP约束混凝土圆柱的峰值应力与峰值应变的计算公式,以及反映轴向—侧向应变关系的三折线计算公式,在此基础上再基于Mander本构模型的主动约束方程,建立有初应力的FRP约束混凝土圆柱应力—应变分析型模型。将该分析型模型和既有模型的计算结果与试验结果进行对比,结果表明:考虑初应力的该分析型模型的计算曲线与试验曲线整体吻合较好,由该分析型模型计算得到的峰值应力和峰值应变与试验结果的误差均在20%以内,优于部分既有模型。

To accurately simulate the uniaxial compression properties of fiber reinforced polymer（FRP）confined concrete with initial stress,based on 103 test data collected and by introducing the influence factor of initial stress level,formulas were proposed for calculating the peak stress and peak strain of FRP confined circular concrete column considering initial stress.The three-line formula was also presented for reflecting the axial-lateral strain relationship.Then,based on the active constraint equations of Manders constitutive model,an analysis-oriented stress-strain model for FRP confined circular concrete column with initial stress was established.The calculated results and test results of the analysis-oriented model and the existing models were compared.Results show that the calculated stress-strain curves obtained by the analysis model are generally in consistence with experimental curves,with less than 20 percent deviation between the calculated peak stress and peak strain values and the test values,better than some existing models.