采用自行开发的自锁锚具，进行17根钢筋混凝土T梁预应力碳纤维布抗剪加固试验以及碳纤维布预应力施加试验，探讨本锚固系统预应力损失以及纤维布应变与扭矩的关系以及不同加固方案下试件的抗剪承载力、挠度变化曲线、碳纤维布各条带的应变分布，分析剪跨比、预载水平、预应力水平、混凝土强度等因素对构件受剪承载力的影响。研究结果表明：此锚固方法能够有效地为碳纤维布施加预应力，能够解决碳纤维布剥离破坏问题，大幅度提高加固梁开裂荷载和极限荷载；在一定范围内，受剪承载力与剪跨比和混凝土强度呈正相关关系；在建议预应力范围内，受剪承载力随着预应力水平的提高而提高，预应力的存在克服了预载对非预应力纤维布抗剪加固的不利影响。%Using an innovative anchorage system, experiments were carried out on 17 RC T-beams shear-strengthened with self-anchored prestressed CFRP laminates. The prestressing losses and the numerical relationship between the strain of CFRP and torque were studied. The shear capacity, load-displacement curves and strain distribution of FRP traps in different reinforcement schemes were studied. The influence factors, i.e., shear span ratio, prestressing level, preloading level and concrete strength on shear resistance were examined in the experimental investigation. The results show that the use of this anchorage system can avoid debonding failure, and significantly improve the cracking and ultimate load capacity so that the tensile capacity of CFRP can be fully employed. The shear capacity is positively correlated to shear span ratio and concrete strength within a certain range. In the range of recommended prestressing level, shear capacity increases with the improvement of prestressing level. The existence of the prestressed CFRP traps compensates for the negative effect brings by preloading.
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