CFRP加固钢筋混凝土梁裂缝研究

Crack Widths of Rectanglar Reinforced Concrete Beams Strengthened with Externally Bonded CFRP Sheets

为了对CFRP抗弯加固钢筋混凝土梁裂缝问题进行系统的试验研究及理论分析,采用批量相同截面尺寸试验梁,包括CFRP粘贴加固梁及未经过加固的对比梁进行抗弯承载力测试,试验过程以配筋率、加固量以及加固前有无预裂3种影响因素为控制参量。结果表明,CFRP粘贴加固可以有效地减小裂缝宽度。在对普通钢筋混凝土梁裂缝宽度计算模式分析研究基础上得到了CFRP加固钢筋混凝土梁裂缝宽度的计算模式和计算公式,理论值与实测值吻合较好,能够作为经验公式在实际工程中进行更为经济合理的CFRP材料加固。

For the purpose of theoretical analysis and experimental analysis on the crack widths of RC beams strengthened with externally bonded CFRP sheets, a batch of same rectangle section RC beams were constructed, includes CFRP strengthened beams and contrast unstrcngthened beams. Three parameters, which are reinforced ratio, strengthening ratio and prc-crack condition, are considered in experiments as the control parameters influent flexural capacity of the beams. All these strengthened or unstrengthened RC beams are statically loaded under four points bending. Structural testing of the beams shows that CFRP strengthening can reduce crack widths efficiently. As the result of the experiment, a model and a computing method for the prediction of crack widths in a repaired specimen is proposed based on the classical theory of reinforced concrete beams.This model are validated by experiments, which is valuable as empirical formula to guide economical and valid CFRP strengthen in actual engineering.