FRP约束混凝土圆柱应力-应变分析模型

为精确模拟FRP约束混凝土的单轴受压性能,提出了FRP约束混凝土圆柱应力-应变分析模型的建立方法.在分析国内外大量试验数据基础上,依据八面体强度准则提出了FRP约束混凝土圆柱极限强度的计算方法,分析FRP约束混凝土圆柱极限应变与侧向约束强度的关系,建立了极限应变的计算方法;分析应力-应变全曲线试验结果中轴向应变与环向应变的关系,建立由轴向应变确定环向应变的计算公式;以Mander本构模型为主动约束关系,采用增量方法计算了FRP约束混凝土圆柱的应力-应变系曲线,模型预测结果与多数试验结果吻合较好.

Stress-strain analytical model for FRP-confined concrete circular column

An analytical stress-strain model for concrete cylinders confined by fibre-reinforced polymer (FRP) was presented to accurately simulate the behavior of FRP-confined concrete under uniaxial compression. Based on large numbers of colleted test data, a new equation for predicting the ultimate compressive strength of FRP-confined concrete circular columns was suggested according to the octahedral theory, and the equation of the ultimate compressive strain was also proposed by considering the lateral confining pressure. The full-range lateral-to-axial strain relationship for FRP-confined concrete circular columns was obtained by analyzing the stress-strain curves measured in tests. Based on above relations, the analytical stress-strain model was generated via an incremental process, in which a stress-strain model for actively-confined concrete proposed by Mander was used as the base model. The predicting results agree well with test data.