基于延性的CFRP-PCPs复合筋嵌贴加固梁的有效预应力计算方法

Effective prestress calculation method based on the ductility of CFRP-PCPs embedded reinforcement beam

设计制作4根底部开槽并用具有不同张拉控制应力的CFRP-PCPs嵌贴加固梁,进行抗弯承载力试验。结果表明,加固梁的抗弯承载力明显提高,加固效果明显。依据平截面假定和材料的应力-应变关系,并基于梁截面的延性对具有不同张拉控制应力的CFRP-PCPs的有效预应力进行推算。将推算结果与试验结果进行对比,发现推算结果的误差在5%左右,表明公式的适用性良好,可以满足工程加固的要求。

Four beams with opened grooves at the bottom were designed and CFRP-PCPs with different tension control stress were embeded in reinforcement beams.Test results show that the reinforced beam flexural capacity increase obviously.The strengthening effect is obvious.If the CFRP-PCPs will be used for reinforcement of practical engineering,it is necessary to apply the prestress to meet the needs of the project.Thus according to the plane section assumption,the stress strain relationship of the material and the ductility of the beam section,the effective prestress of CFRP-PCPs with different tension control stress were calculated.Compared the calculated results with the experimental results,it is found that the error of the calculation is about 5%,and the formula is of good applicability and can meet the requirements of engineering reinforcement.