基于长宽比变化的FRP加固混凝土轴压矩形柱的试验研究

EXPERIMENTAL STUDY OF FRP-STRENGTHENED RECTANGULAR CONCRETE AS AFFECTED BY ASPECT RATIO

制作了16根FRP加固混凝土矩形短柱进行轴压试验,按长宽比值不同分成4组,每组4个构件,其中1个未加固,2个无间隙粘贴FRP环向围束加固,1个有间隙粘贴FRP环向围束加固。通过考虑柱截面长宽比、FRP材料类型、粘贴方式等因素的变化,分析探讨了加固前后柱的承载力、延性、破坏形式等。试验表明,长宽比值在提高柱的极限承载力方面影响较大,而在提高柱的延性方面影响较小。根据试验数据对我国混凝土加固规范推荐的公式进行对比,提出了FRP有间隙粘贴环向围束的强度模型。

Sixteen concrete columns which is strengthened with FRP sheets were fabricated and studied.The specimens were divided into four groups according to the aspect ratio.One is a control column which is unreinforced,two columns are reinforced by full wrapping with FRP sheet,and one is reinforced by partial wrapping with FRP sheet.The failure mode,bearing capacity and ductility of columns were studied by considering the changes of aspect,the type of the FRP and reinforcement.It was shown that the aspect ratio showed obvious influence on the obtained capability ductility,but had a weak influence on the ductility.The formula recommended by the code for strengthening concrete is verified.According to the test data,a modified model is suggested about the column reinforced by partial wrapping with FRP sheet.