长期腐蚀环境影响下GFRP筋混凝土构件的老化机理及抗弯性能研究

为了研究长期腐蚀环境影响下GFRP筋混凝土构件的老化机理以及抗弯性能,分别分析了水分、温度、碱性环境等因素对GFRP筋抗拉强度、有效受拉面积和粘结强度等性能方面的影响。基于GFRP筋材料老化后与混凝土协同工作关系的变化,通过构造新的几何条件,推导了老化GFRP筋正截面抗弯承载力计算公式,利用推导的公式分析了不同GFRP筋老化率对构件承载力的影响。研究表明:GFRP筋混凝土构件在腐蚀环境长期作用下,GFRP筋不断老化,其抗拉强度、有效受拉面积以及粘结性能都有不同程度的降低;随着GFRP筋材料老化率的不断增加,构件抗弯承载力损失率也不断增加,当老化率达到27%时,构件抗弯承载力也相应损失了25.97%。

STUDY ON THE AGING MECHANISM AND FLEXURAL BEHAVIOR OF GFRP REINFORCED CONCRETE MEMBERS UNDER LONG-TERM CORROSION ENVIRONMENT

In order to study the aging mechanism and flexural behavior of GFRP reinforced concrete members under long-term corrosion environment,the effects of moisture,temperature and alkali environment on the tensile strength,effective tensile area and bond strength of GFRP bar were analyzed separately.Based on the change of the relationship between the material aging and cooperative work with concrete,the calculating formula of the flexural capacity of the normal section of the aging GFRP bar is derived by constructing the new geometrical condition,and using the derived formula to analyze the influence of aging rate on the bearing capacity of the component.The researches show that GFRP reinforced concrete member under the 1ong-term effect of the corrosion environment,GFRP tendons aging,its tensile strength,effective tensile area and bond properties have different degrees of reduction.As the aging rate of GFRP reinforced materials increases,the loss rate of flexural capacity of the component is also increasing.When the aging rate is 27％,the flexural capacity of the component is also lost by 25.97％.