碳纤维布约束混凝土矩形柱的抗压性能研究

对碳纤维布约束的混凝土柱(从方形截面逐步过渡至圆形截面)进行了轴压性能试验。试验研究了碳纤维布约束混凝土柱的破坏形态及轴压应力与轴向、横向应变之间的变化曲线,确定了碳纤维布的有效应变系数。探讨了FRP材料约束混凝土矩形柱的侧向约束机理;提出了新的有效约束面积模型及侧向约束压力计算公式。基于现有试验研究成果,建立了碳纤维布约束混凝土矩形柱的抗压强度与峰值应变计算模型。针对碳纤维布充足约束混凝土矩形柱的应力-应变反应,提出了双线性理论模型,理论计算曲线与试验曲线基本吻合。

A study on the compressive performance of rectangular concrete columns confined with CFRP sheets

Cross sections of concrete columns varying gradually from square to circular,wrapped with carbon fiber reinforced polymer(CFRP)sheets,were experimentally studied.The relationships between the axial compressive stress,axial and lateral strains of the concrete columns were analyzed,an efficiency factor of CFRP strain is proposed and the lateral confinement mechanism of FRP materials for rectangular columns is explored.New formulae for effective confinement area and lateral confinement pressure are proposed.Models for predicting compressive strength and its corresponding strain are developed on the basis of existing results.A bilinear stress-strain model is suggested for predicting the entire stress-strain curve of adequately CFRP-confined columns.The theoretical curves agree well with the experimental data.