FRP约束混凝土圆柱应力-应变分析模型

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

摘要:

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.

Abstract:

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 FRPconfined concrete circular columns was suggested according to the octahedral theory,and an equation for calculating 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.Then an 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 basic model.It is found that the predicting results agree well with test data.